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    Prozessbausteine
    (2014) Eberle, Hanna; Leymann, Frank (Prof. Dr.)
    Gegenwärtig existierenden Modellierungssprachen und Werkzeugen zur Umsetzung prozessbasierter Anwendungen liegt im Allgemeinen die Annahme eines zur Entwicklungszeit bekannten und in seiner Struktur vollständig ausmodellierten Prozessmodells zugrunde. Für Szenarien, in welchen eine prozessbasierte Anwendung neben stabilen, d.h. zur Modellierungszeit des Prozesses bekannten, auch durch dynamische, d.h. erst zur Anwendungslaufzeit geltende, Rahmenbedingungen beeinflusst wird, ist eine derartige statische Prozessmodellierung nur bedingt geeignet. In diesen Szenarien ist es vielmehr wünschenswert, (i) zur Entwicklungszeit bereits bekannte Prozessteile der Anwendung detailliert ausmodellieren zu können, und diese (ii) zur Laufzeit der Anwendung unter Berücksichtigung der zum Ausführungszeitpunkt geltenden dynamischen Rahmenbedingungen zum vollständigen Prozess der Anwendung zu integrieren. Das im Verlauf dieser Arbeit vorgestellte Konzept der Prozessbausteine setzt an diesem Punkt an und schafft ein Rahmenwerk für die Modellierung und Ausführung prozessbasierter Anwendungen unter Berücksichtigung sowohl stabiler als auch dynamischer Rahmenbedingungen. Kerngedanke des Konzepts ist die Abbildung stabiler Rahmenbedingungen zur Entwicklungszeit in Form teilweise unvollständiger Prozessmodelle, sogenannter Prozessbausteine. Zu einem späteren Zeitpunkt im Lebenszyklus der Anwendung werden diese Prozessbausteine dann, motiviert durch die jeweils geltenden dynamischen Rahmenbedingungen, mit weiteren Prozessbausteinen zum vollständigen Prozessmodell der Anwendung integriert. Zur vollständigen Unterstützung der Entwicklung von Anwendungen auf Grundlage dieses Konzepts umfasst die vorliegende Arbeit die Definition eines Metamodells für sowohl die Modellierung einzelner als auch die Repräsentation integrierter Prozessbausteine, die Beschreibung der Ausführung integrierter Prozessbausteine, sowie die Vorstellung einer Architektur für die Ausführung integrierter Prozessbausteine.
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    Colloidal monolayers on quasiperiodic laser fields
    (2010) Mikhael, Jules; Bechinger, Clemens (Prof. Dr.)
    Quasicrystals are somewhat paradoxical structures which exhibit many amazing properties distinguishing them from ordinary crystals. Although the atoms are not localized at periodic positions, quasicrystals posses perfect long-range order. Until the early 1980s it was unanimously established that ordered matter is always periodic. Accordingly, the rotational symmetry in real space was thought to be limited to n=2,3,4 and 6. However more than a hundred complex metal alloys, for instance the discretely diffracting icosahedral AlPdMn or decagonal AlNiCo, have defied these crystallographic rules and self-organized into quasicrystals. Although the majority of the identified quasicrystals are complex metal alloys synthesized in the laboratory, recent experimental results proved that quasiperiodic order is not limited to metals. Matter also organizes itself aperiodically at larger length scales where thermal fluctuations play an important role. Recent experiments have shown that quasiperiodic order is also oberved in soft matter systems, such as micellars, polymers, and binary nanoparticles. Quasicrystals show many interesting properties which are quite different from that of periodic crystals. Accordingly, they are considered as materials with high technological potential e.g. as surface coatings, thermal barriers, catalysts or photonic materials. Quasicrystalline structures have been theoretically predicted also in systems with a single type of particles. Nevertheless, experimentally their spontaneous formation has been only observed in binary, ternary or even more complex alloys. Accordingly, their surfaces exhibit a high degree of structural and chemical complexity and show intriguing properties. In order to understand the origin of those characteristics it would be helpful to disentangle structural and chemical aspects which can be achieved by growing single-element monolayers to quasicrystalline surfaces. Apart from understanding how quasicrystalline properties can be transferred to such monolayers, this approach might allow fabrication of materials with novel properties. First heteroepitatic growth experiments on decagonal and icosahedral surfaces indeed demonstrate the formation of Pb, Bi and Sb monolayers with a high degree of quasicrystalline order as determined by low-energy electron diffraction and elastic helium atom scattering experiments. Compared to reciprocal space studies, only recently atomically resolved scanning tunneling microscopy investigations of the adsorbate morphology became possible. Even then, however, it is difficult to relate the structure of the adsorbate to that of the underlying substrate. In that respect, the study of the phase behaviour of colloidal particles interacting with quasiperiodic laser fields can throw new light on fundamental problems of broad interest in the physics of quasicrystals and in condensed matter physics. In fact colloidal systems are meanwhile established as excellent model for atomic systems and colloidal physics have demonstrated that such systems can give answers to many basic physics questions. Depending on the pair-interaction and the concentration, colloidal systems show analogues of all the states of atomic systems: gas, liquid and solid states. The mesoscopic size (nm-µm), the time scales (ms-s) and the tunability of the pair interaction in colloidal systems make them a convenient model system for experimental and theoretical studies. As a consequence, real space analysis by means of video microscopy allows tracking the trajectories of the individual particles and makes the time evolution of the system accessible in detail. Such information is inaccessible in systems investigated by diffraction experiments, as the scattering information is available only averaged over the scattering area. Because in a colloidal system there is direct access to real space information, the strength and nature of the different interactions, the origins of the complex phase behavior could be in different examples identified. In conclusion, the study of the rich phase behavior of colloidal suspensions provides ideal conditions for experimental and theoretical studies. In this Thesis, we report on a real-space investigation of the phase behaviour of charged colloidal monolayers interacting with quasicrystalline decagonal or tetradecagonal substrates created by interfering five or seven laser beams. Different starting configurations, such as dense fluid and triangular crystals with different densities, are prepared. At low intensities and high particle densities, the electrostatic colloidal repulsion dominates over the colloid-substrate interaction and the crystalline structure remains mainly intact. As expected, at very high intensities the colloid-substrate interaction dominates and a quasiperiodic ordering is observed. Interestingly, at intermediate intensities we observe the alignment of crystalline domains along the 5 directions of the quasicrystalline substrate. This is in agreement with observations of Xenon atoms adsorbed on the ten-fold decagonal Al-Ni-Co surface and numerical simulations of weakly adsorbed atomic systems. Intermediate phases are observed for colloid-substrate interactions strong enough to produce defects in the crystal. These defects adapt the form of rows of quadratic tiles. Surprisingly, for specific particle densities (at which the colloid-substrate interaction is minimized) we identify a novel pseudomorphic ordering. This intermediate phase which exhibits likewise crystalline and quasicrystalline structural properties can be described by an Archimedean-like tiling consisting of alternating rows of quadratic and triangular tiles. The calculated diffraction pattern of this phase is in agreement with recent observations of copper adsorbed on icosahedral AlPdMn surfaces. Interestingly, we also observe the formation of the same phase on tetradecagonal substrates also at densities for which the potential energy of the colloidal system is minimized. Although the structure can also be described by rows of triangles and rows of squares, a closer analysis reveals substantial differences. Here, large domains with almost periodic ordering are found. We show that this behavior is closely related to the low density of highly symmetric local motifs in the substrate potential. In the second part of this Thesis the conditions under which quasicrystals form are investigated. Currently, it is not clear why most quasicrystals hold 5- or 10-fold symmetry but no single example with 7 or 9-fold symmetry has ever been observed. Since the properties of quasicrystals are strongly connected to their atomic structure, a better understanding of their growth mechanisms is of great importance. In contrast to crystals which are periodic in all three dimensions, quasiperiodicity is always (except for icosahedral quasicrystals) restricted to two dimensions. Accordingly, three-dimensional quasicrystals are comprised of a periodic stacking of quasiperiodic layers and any hurdle in the formation of quasiperiodic order within a single layer will eventually prohibit their growth along the periodic direction. In this Thesis, we also report on geometrical constraints which impede the formation of quasicrystals with certain symmetries in a colloidal model system. This is achieved by subjecting a colloidal monolayer to N=5- and 7-beam quasiperiodic potential landscapes. Our results clearly demonstrate that quasicrystalline order is much easier established for N = 5 compared to N = 7. With increasing laser intensity we observe that the colloids first adopt quasiperiodic order at local areas which then laterally grow until an extended quasicrystalline layer forms. As nucleation sites where quasiperiodicity originates, we identify highly symmetric motifs in the laser pattern. We find that their density strongly varies with n and surprisingly is smallest exactly for those quasicrystalline symmetries which have never been observed in atomic systems. Since such high symmetry motifs also exist in atomic quasicrystals where they act as preferential adsorption sites, this suggests that it is indeed the deficiency of such motifs which accounts for the absence of e.g. materials with 7-fold symmetry. In addition to the fundamental aspects, we report in this Thesis on the fabrication of large colloidal quasiperiodic layers incorporated in a polymer hydrogel matrix. Because quasicrystals have higher point group symmetry than ordinary crystals, micrometer-scale quasicrystalline materials are expected to exhibit large and isotropic photonic bandgaps in the visible range. In our case, the quasiperiodic symmetries are induced using extended light fields. The reported gelled colloidal quasicrystals are unique in that they have large sizes as well as good optical uniformity. With laser diffraction the in situ variable length scale of such materials is demonstrated. In conclusion, we have studied the phase behavior of charged colloidal particles interacting with quasiperiodic laser fields. We showed that novel pseudomorphic growth can lead to the formation of a phase which exhibits likewise crystalline and quasicrystalline structural properties. We also performed unconventional measurements in order to understand why the formation of quasicrystals is limited to specific rotational symmetries. We have found that geometrical hurdles play a crucial role in the proliferation of quasiperiodicity and that such hurdles can hindered or even prohibited the formation of e.g. 7- or 9-fold symmetry. And finally, we have shown that the combination of extended light fields and hydrogel matrices leads to the formation of large quasiperiodically ordered colloidal materials.
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    Application-specific UML profiles for multidisciplinary product data integration
    (2011) Reichwein, Axel; Rudolph, Stephan (Priv.Doz. Dr.-Ing.)
    This thesis examines the suitability of the UnifiedModeling Language (UML) to establish a central product model for multidisciplinary product data integration. Computer-aided product design involves the use of specialized discipline-specific software applications in order to model and simulate various product aspects. Dependencies between models are thereby frequent as the same product information often appears redundantly in various engineering models. In addition, dependencies exist due to relationships between distinct features of various models. As a result, model modifications frequently require the update of dependent models. Data consistency between models is achieved automatically through model-to-model data exchange software. The use of a central product model enables to reduce the required number of data exchange connections. Central product models store product information which is spread across several models and achieve data consistency through data exchange connections between themselves and specific models as in a hub-and-spoke network. Central product models are especially useful for automatic data consistency in design scenarios which include a high number of inter-model dependencies and model modifications. The integration of geometry and therefrom derived models such as structural analysis or computational fluid dynamics models has already been successfully addressed in numerous central product models. However, the multidisciplinary integration of more diverse models, such as geometric, software, controller and multibody system models, currently presents a challenge. Although several central product models have been developed for multidisciplinary design, none has yet gained, in contrast to geometry-focused central product models, wide acceptance nor reached the status of an international standard. The unmanageable high number of diverse discipline- and application-specific modeling concepts hinders the development of a standardized holistic central product representation. This thesis investigates the possibility of establishing an interdisciplinary central product model based on the common modular structure of models from various disciplines. Most models which are edited with current state-of-the-art software applications are composed of modular components in order to support the exchange and reuse of model information. Models from different disciplines therefore share common modeling concepts for the specification of modular model components. However, there is yet no overarching modeling standard to describe the common characteristics of modular model components from various disciplines. Object-oriented modeling concepts currently mainly describe software modules called objects. Object-oriented modeling concepts are generic and can be used to represent modular components in general. The Unified Modeling Language (UML) has been since its emergence in 1997 the de facto standard for object-oriented modeling. This thesis examines the use of the object-oriented modeling concepts of the UML to uniformly describe widely used application-specific geometric, dynamic and multibody system models in a central product model. Application-specific model information was represented in UML through generic UML modeling concepts in combination with lightweight UML extensions in the form of stereotypes. UML profiles regrouped stereotypes which corresponded to a specific modeling application. The automatic translation of UML model information into the specific models and vice versa was implemented in order to test and validate the application-specific UML profiles. The UML-based central product model was used in several test cases to automatically generate consistent models for the simulation and evaluation of various product configurations. The test cases included models for the simulation of slider-crank mechanisms, the evaluation of cabin pressure control systems, the design of conveyor system configurations, the evaluation of satellite configurations and the generation of customized aircraft geometry. The workflows within the test cases included the automatic creation and modification of UML models as well as the invocation of data exchange connections. The workflows were described in executable UML activity diagrams or Java programs. The thesis demonstrates that the UML can be used beyond conventional software modeling to establish a central holistic product representation. The modeling concepts of geometric, dynamic and multibody system models were translated mostly according to one-to-one mappings into corresponding UML modeling concepts with their respective stereotype. As a result, the specific model information is easily recognizable in the UML-based central product model. Furthermore, the use of a UML-based central product model is facilitated for the many modelers who are already familiar with the widespread and standardized UML modeling language.
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    Mechanistic studies on the DNA methyltransferases DNMT3A and DNMT3B
    (2021) Dukatz, Michael; Jeltsch, Albert (Prof. Dr.)
    In this work, both regulatory and catalytic mechanisms of de novo methyltransferases were investigated, which include interactions with other proteins and the specific recognition of the substrate sequence. Another part of this work strived to elucidate how enzymatic generation of 3-methylcytosine by DNMT3A can occur.
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    Eignung von metallorganischen Gerüstverbindungen als stationäre Phase in der Hochleistungsflüssigchromatographie (HPLC)
    (2017) Lieder, Christian; Klemm, Elias (Prof. Dr.-Ing.)
    Anwendung von metallorganischen Gerüstverbindungen als stationäre Phase in der HPLC, Vergleich mit klassischen Silika-Materialien. Synthese der metallorganischen Gerüstverbindungen, Modifizierung. Befüllung chromatographischer Säulen und Gegenüberstellung der Füllmethoden. Methodenentwicklung, Einflüsse auf chromatographische Ergebnisse. Chirale Erkennung, Untersuchung der Wechselwirkungen. Theoretisch chemische Berechnungen der Wechselwirkungen.
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    Synthetic and mechanistic prospects of homogeneous gold catalysis
    (2009) Pankajakshan, Sreekumar; Hashmi, A. Stephen K. (Prof. Dr.)
    a) The first chapter of this thesis manifests the exploration of homogeneous gold-catalyzed conversions of furan containing aryl-ynamides and ynol ethers. Enynes boast to be the most explored substrate structures in the realm of homogeneous gold catalysis, whereas the reactivity of ene-ynamides and ene-ynol ethers are much less explored till date.34, 45 Hashmi and co-workers recently reported the homogeneous gold-catalyzed synthesis of phenols from furan containing ynamides/ynol ethers.45e These substrates showed excellent reactivity and selectivity apparently owing to the heteroatom directly attached to the alkyne unit. Impressed with the reactivity and high selectivity of these systems, we decided to explore the catalytic activity of the aryl substituted variants of these compounds. Gold catalysis of aryl-ynamides The aryl-ynamide substrates turned out to be interesting candidates for gold catalysis. The mode of reactivity depended on the tether length. The substrates with two carbon tether underwent a Friedel-Crafts type reaction upon subjected to gold catalysts and furnished benzannulated arenes in moderate to excellent yields (Scheme C). A combination of Ph3PAuCl /AgBF4 (5 mol%, 1:1) in CH2Cl2 or CHCl3 was found to be the best choice of catalyst. The reaction conditions were mild and a broad spectrum of polyarenes and polyheteroarenes were synthesized. The substrates carrying an unactivated arene failed to react even under higher temperature and prolonged reaction time. The gold catalysis of substrates 58r-58t with a longer tether took a completely different pathway and gave rise to cyclopentadiene structures (Scheme D). Similar to shorter tethered substrates, electron withdrawing groups on the arene were not tolerated. b) The second chapter of this thesis deals with the development of gold-catalyzed transformations of furan containing alkynes that prove the potential intermediacy of a cationic intermediate in these types of reactions. The actual electronic state of the intermediate in gold-catalyzed enyne cycloisomerizations is a hot spot in recent scientific reports.20a-c A cyclopropyl "carbene" form of the intermediate has been used by most of the authors. But it is important to note that such a species is yet to be isolated or characterized spectroscopically. Recently Fürstner et al., proposed remarkable experimental evidence for the involvement of the cationic form of this intermediate in gold-catalyzed cyclizations.20a,20c The scenario demands the consideration of the actual electronic state of the intermediate as a mesomeric/tautomeric package of different canonical forms (Scheme H). In the context of this thesis it was found that furyl-alkynes carrying electron donating substituents in the α-position of the tether led to the formation of unexpected five-membered structures (instead of the expected phenols) when subjected to gold catalysts (Scheme I). The observed reactivity pattern for the substrates 116/118 was highly informative and served as an experimental evidence for the significant contribution of the cationic form of the intermediate AO in the mesomeric/tautomeric equilibria shown in the scheme H. A mechanistic proposal based on this intermediate was suggested for this hitherto unknown transformation in the gold catalysis of furyl-alkynes (Scheme J). c) The third chapter of this thesis elaborates the unexpected formation of N,O-acetals from oxanorbornadienes-the potential precursors for phenols- upon exposure to gold and other Lewis acids (Scheme K). AuCl was found to be the best Lewis acid catalyst under the given conditions, and Yb(CF3SO3)3 also showed remarkable reactivity. The generality and the absence of any other products/side products confirmed that the reactions followed general acid catalysis. The observation that there is a net reversal in the connectivity of the tether in the product hinted at a complex mechanism operating in the process. d) The fourth chapter of this thesis describes the investigations carried out on the aerobic oxidation reactions catalyzed by gold. A homogeneous catalytic system comprising of gold(I) chloride, n-butyl lithium and sodium carbonate was developed and was found to oxidize primary aromatic alcohols to aldehydes. The system was poor in activity towards aliphatic and secondary alcohols (Scheme L).
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    Optical and magneto-optical investigations on 3D Dirac- and Weyl-semimetals
    (2017) Neubauer, David; Dressel, Martin (Prof. Dr.)
    This work concentrates on optical investigations on 3D Dirac- and Weyl-semimetals with and without applied magnetic fields. Four compounds are extensively discussed, namely the 3D Dirac semimetal Cd3As2, the Weyl semimetals TaAs and NbP, and finally evidence is found for 2D Dirac states in the iron based superconductor FeSe. For the measurements in magnetic fields a novel magneto-optical installation is designed and implemented in the lab. The design principle and characterization of this setup is presented.
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    Defined polymer architectures enabled by yttrium-mediated ring-opening polymerization of renewable lactones
    (2025) Hornberger, Lea-Sophie; Buchmeiser, Michael R. (Prof. Dr.)
    Although global plastic production exceeds 410 million tons annually, less than 0.7 % currently originates from bio-based sources. Given the finite fossil resources and the low biodegradability of conventional plastics, the development of polymers from renewable feedstocks offers considerable potential. This highlights the largely unexploited opportunities offered by renewable monomers. Ring-opening polymerization (ROP) enables the synthesis of polyesters with precise control over molar mass, polydispersity, and architecture, while reversible-deactivation radical polymerization (RDRP) techniques such as atom transfer radical polymerization (ATRP) provide complementary strategies for post-polymerization modification of functional polyesters. This dissertation employs aminoalkoxy bis(phenolate) yttrium complexes for the controlled ROP of lactones from renewable resources, systematically expanding the accessible monomer scope from small, strained four-membered rings to unstrained macrolactones and functional seven-membered terpene-derived lactones. In the first part, the entropy-driven ROP of the 16-membered macrolactone ω pentadecalactone (PDL) was achieved under controlled conditions, affording high-molar-mass poly(ω-pentadecalactone) (PPDL) with moderate polydispersities. Its aliphatic backbone makes PPDL a promising sustainable analogue to polyolefins. Sequential block copolymerization with the four-membered racemic β-butyrolactone (BBL) yielded semi-crystalline materials that integrate the crystalline domains of both homopolymers, enabling tunable material properties. The second part investigated the effect of substitution pattern and stereochemistry on the polymerization kinetics and mechanism of the seven-membered terpene-based (-)-menthide and (+)-carvomenthide, which differ only in the relative positions of their substituents. Kinetic analysis combined with density functional theory (DFT) calculations revealed that subtle stereoelectronic differences strongly impact activation parameters, propagation rates, and susceptibility to side reactions. In (-)-menthide, the isopropyl group adjacent to the reactive ester moiety introduces steric hindrance and increases the activation, whereas the reduced steric demand near the ester in (+)-carvomenthide enables faster propagation but also promotes side reactions. These findings provide valuable guidelines for the rational design of terpene-based lactones. The third part focused on trans (+)-dihydrocarvide (DHC), a seven-membered lactone bearing a pendant isopropenyl group. ROP of DHC produced amorphous poly(dihydrocarvide) (PDHC) with full retention of the double bond. Block copolymerization with semi-crystalline PPDL or syndiotactic poly(3-hydroxybutyrate) (PHB) introduced crystallinity and phase separation. The pendant double bonds in PDHC were further functionalized via thiol-ene chemistry to generate ATRP macroinitiators, enabling orthogonal grafting-from polymerizations of ethyl acrylate that afforded high-density polyester-based brush architectures. Overall, the combination of yttrium-mediated ROP with orthogonal post-polymerization techniques enables the construction of renewable polyester architectures such as block and graft copolymers that integrate amorphous, semi-crystalline, and functional segments. This modular approach offers a versatile platform to tailor thermal, mechanical, and functional properties, providing new opportunities for advanced biomedical and high-performance materials.
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    Referenzmodell zur Gestaltung der Serviceorganisation in Unternehmen der Raumfahrtbranche zum Betrieb bemannter Raumfahrtsysteme
    (2013) Forster, Christoph; Westkämper, Engelbert (Univ. Prof. em. Dr.-Ing. Prof. e. h. Dr.-Ing. E. h. Dr. h. c. mult.)
    Aufgrund der stark fortschreitenden industriellen und kommerziellen Nutzung des Weltraums, der Verlagerung von bemannten Raumfahrtaktivitäten auf Industrieunternehmen und aufgrund von Trends wie dem Weltraumtourismus gewinnt in Unternehmen der Raumfahrtbranche der Service für Betrieb und Nutzung bemannter Raumfahrtsysteme neben dem ursprünglichen Kerngeschäft der Entwicklung und Herstellung dieser Systeme zunehmend an Bedeutung. Zugleich aber stellt dies die Unternehmen vor große Herausforderungen. Bei der praktischen Umsetzung der Gestaltung einer serviceorientierten Prozessorganisation und der Serviceprozesse für den Betrieb von bemannten Raumfahrtsystemen sind erhebliche Probleme in den Raumfahrtunternehmen zu beobachten, da derzeit keine methodischen Hilfsmittel für die operative Gestaltung des Service zum Betrieb bemannter Raumfahrtsysteme existieren. Das in dieser Arbeit entwickelte und realisierte Referenzmodell schließt diese bestehende methodische Lücke und stellt die allgemeingültigen und unternehmensübergreifenden Serviceprozesse sowie die prozess- und kundenorientierte Serviceablauforganisation für den Betrieb bemannter Raumfahrtsysteme dar. Das Referenzmodell ist durch die End-to-End-Betrachtung der Serviceprozesse ein konsistentes Modell, das durch einen modularen hierarchischen Aufbau sowie eine Dekomposition in die Funktionssicht und die Prozesssicht auf der Fachebene gekennzeichnet ist. Entsprechend dem prozessfokussierten Anwendungszweck ist das Modell in 6 Prozesskategorien, 18 Prozessbausteine und 225 Basisfunktionen aufgegliedert und strukturiert. Das Referenzmodell ist dazu geeignet, Unternehmen der Raumfahrtbranche bei der Gestaltung und Verbesserung der Serviceprozesse sowie der Gestaltung einer serviceorientierten Prozessorganisation für den Betrieb bemannter Raumfahrtsysteme während der gesamten Nutzungsphase zu unterstützen. Dabei steht die Effektivitätsverbesserung der Serviceprozesse im Vordergrund. Für die Wiederverwendung des Referenzmodells wird eine Vorgehensweise zur Gestaltung unternehmensspezifischer Serviceprozessmodelle auf Basis des entwickelten Referenzmodells und der wiederverwendbaren Referenzmodellelemente (Prozesskategorien, Prozessbausteine, Basisfunktionen) entwickelt. Das Referenzmodell und die Methode zu seiner Wiederverwendung werden in zwei Anwendungsfällen zur Gestaltung spezifischer Serviceprozessmodelle in Unternehmen der Raumfahrtbranche für den Betrieb eines bemannten Raumfahrtsystems verifiziert. Dabei wird die die Eignung des Referenzmodells zur Gestaltung effektiver und effizienter Serviceprozesse für den Betrieb bemannter Raumfahrtsysteme nachgewiesen.