Techn. Hochsch., Diss., 2001--Aachen.

Diese Dissertation besteht aus drei unabhängigen Kapiteln über mikroökonomische Themen. Die ersten beiden Kapitel befassen sich mit Themen der Industriökonomie und Wettbewerbstheorie, wohingegen das dritte Kapitel Fragestellungen von Cheap Talk Spielen untersucht. Kapitel 1 untersucht die Folgen, die sich aus einer partiellen Akquisition zwischen Wettbewerbern ergeben. Kapitel 2 analysiert die Auswirkungen einer Forschungs-und Entwicklungs (FuE)- Kooperation auf die Investitionsanreize in einem Markt, in dem eine Mehrproduktunternehmer mit einem Einzelproduktuntfirma konkurriert. Kapitel 3 untersucht die Funktion der Mediation zur Erleichterung der Kommunikation mit privaten Informationen. / This dissertation consists of three independent chapters in the field of microeconomics. The first two chapters are concerned with topics of industrial organization and competition policy, whereas the third chapter addresses some problems in cheap talk games. Chapter 1 studies anti-competitive issues that arise from partial acquisition between competitors. Chapter 2 analyzes the effects of cooperation on R&D investment incentives in a market where a multi-product firm competes with a single-product firm. The third chapter examines the role of mediation in facilitating communication with private information.

Purpose: We determined the indication, outcome and risk factors of single and multiple hematopoietic stem cell transplantation(s) (HSCT) in children and adolescents mostly with advanced disease. Methods: Forty-one out of 483 patients (8.5%; median age 9 years) diagnosed at the University of Leipzig with haematological and oncological diseases required HSCT from 1999 to 2011. Results: Patients had overall survival (OS) of 63±10% and 63±16%, event-free survival (EFS) of 57±10% and 42±16%, relapse incidence (RI) of 39±10% and 44±18% and non-relapse mor-tality (NRM) of 4±4% and 13±9% at 10-years after one or more HSCT for allogeneic and autologous HSCT, respectively. One patient in complete remission (CR)1 and five with advanced disease received two HSCT. Four of the six patients maintained/achieved CR for a median of 13 months. Three died of progression and one of NRM. Two patients had a third HSCT and one survived in CR +231 days after HSCT. Risk factors for OS and EFS were disease stage at HSCT and EBMT risk-score. Center (paediatric or JACIE accredited paediatric/adult) was not a determinant for survival. Conclusion: Paediatric single and multiple HSCT are important curative approaches for high-risk malignant diseases with low NRM. Efforts to reduce high RI remain the major aim.

In der vorliegenden Arbeit wurde das Phasenverhalten von harten Hantelteilchen (Dumbbells) als Funktion des Aspektverhältnisses (L*, der Quotient aus dem Abstand der Massenzentren zum Durchmesser der Kugel) und der Volumendichte untersucht. Bragg-Reflexe weisen darauf hin, das harte Dumbbells mit L* < 0.4 einen Phasenübergang von einer Fluid-artigen Phase zu einem plastischen Kristall zeigen. Die experimentellen Phasendiagramme bei L* ~ 0.24 und L*~ 0.30 sind vergleichbar mit Vorhersagen aus Monte Carlo-Simulationen. Rheologie Messungen zeigen, dass harte Dumbbells verschiedene Gleichgewichts- und Nichtgleichgewichtsphasen annehmen. Suspensionen von harten Dumbbells im Zweiphasenbereich zeigen ein einziges Fließgrenzen-Ereignis, wohingegen in der plastischen Kristallphase zwei Fließgrenzen-Ereignisse beobachtet werden. Diese, im Folgenden als „double yielding“ bezeichneten Ereignisse, hängen mit der Kristallisation der Suspensionen von harten Dumbbells zusammen. Die entsprechende Strukturentwicklung wurde mit rheo-SANS-Experimenten untersucht und mithilfe von BD Simulationen interpretiert. Es konnte gezeigt werden, dass die plastische Kristallphase polykristallin im Ruhezustand ist. Unter schwacher Scherung wird eine fcc-Schwerzwilling Struktur ausgebildet. Bei hoher Scherung formt sich eine teilweise orientierte Struktur aus gleitenden Schichten. Zwischen diesen beiden Strukturen existiert eine ungeordnete Übergangsphase. Die Scher-induzierte Strukturausbildung eintspricht dem „double yielding“ Ereignis der kristallinen harten Dumbells. Es wurde gezeigt, dass ein größeres L* (L* < 0.4) die Strukturentwicklung unter Scherung qualitativ nicht beeinflusst. Aufgrund verlangsamter Dynamik in der Nähe des Glasübergangs sind lediglich stärkere oder längere Oszillationen von Nöten, um Scher-induzierte Kristallisation zu erzeugen. Im zweiten Teil dieser Arbeit werden Systeme aus hohlen Kugeln und „Janus“-Dumbbells vorgestellt, die als kolloidale Modellsysteme dienen können. / In the present work the phase behaviour of hard dumbbells has been explored as a function of aspect ratio (L*, the center to center distance to the diameter of one composed sphere) and volume fractions using thermosensitive dumbbell-shaped microgels as the hard dumbbell model system. A fluid-to-plastic crystal phase transition indicated by Bragg reflections has been observed for L* < 0.4. The experimental phase diagrams at L* ~ 0.24 and L* ~ 0.30 are comparable to the theoretical prediction of the Monte Carlo simulations. Rheological measurements reveal that the hard dumbbells in the biphasic gap show the yielding behaviour with a single yielding event, while two yielding events have been observed for the plastic crystalline phase. The two yielding events, referred to as the double yielding behaviour, are proved to be related to the crystallization of hard dumbbells. The underlying structural evolution has been investigated by rheo-SANS experiments and the scattering data has been interpreted by BD simulations. It is demonstrated that the plastic crystal structure of the hard dumbbells is polycrystalline at rest, which has been induced into the twinned fcc structure at low strain, the partially oriented sliding layers at high strain and the intermediate state at the strain in-between. The shear-induced structural evolution corresponds to the double yielding events of the fully crystallized hard dumbbells. Additionally, we prove that the increase of L* (L* < 0.4) does not change the structural evolution of the sheared hard dumbbells. Only more extensive or longer oscillations are required to form the shear-induced crystal structures due to the slowdown of the dynamics in the vicinity of the glass transition. In a second part, the work of this thesis is extended to hollow systems composed of hollow spheres and hollow Janus dumbbells that can be used as model systems to probe phase behaviour of hollow capsules.

The prediction of fracture in thin-walled structures is decisive for a wide range of applications. Modeling methods such as the phase-field method usually consider cracks to be constant over the thickness which, especially in load cases involving bending, is an imperfect approximation. In this contribution, fracture phenomena along the thickness direction of structural elements (plates or shells) are addressed with a phase-field modeling approach. For this purpose, a new, so called “mixed-dimensional” model is introduced, which combines structural elements representing the displacement field in the two-dimensional shell midsurface with continuum elements describing a crack phase-field in the three-dimensional solid space. The proposed model uses two separate finite element discretizations, where the transfer of variables between the coupled twoand three-dimensional fields is performed at the integration points which in turn need to have corresponding geometric locations. The governing equations of the proposed mixed-dimensional model are deduced in a consistent manner from a total energy functional with them also being compared to existing standard models. The resulting model has the advantage of a reduced computational effort due to the structural elements while still being able to accurately model arbitrary through-thickness crack evolutions as well as partly along the thickness broken shells due to the continuum elements. Amongst others, the higher accuracy aswell as the numerical efficiency of the proposed model are tested and validated by comparing simulation results of the new model to those obtained by standard models using numerous representative examples.

In vielen Anwendungen ist es notwendig, die stochastische Schwankungen der maximalen Abweichungen der nichtparametrischen Schätzer von Quantil zu wissen, zB um die verschiedene parametrische Modelle zu überprüfen. Einheitliche Konfidenzbänder sind daher für nichtparametrische Quantil Schätzungen der Regressionsfunktionen gebaut. Die erste Methode basiert auf der starken Approximation der empirischen Verfahren und Extremwert-Theorie. Die starke gleichmäßige Konsistenz liegt auch unter allgemeinen Bedingungen etabliert. Die zweite Methode beruht auf der Bootstrap Resampling-Verfahren. Es ist bewiesen, dass die Bootstrap-Approximation eine wesentliche Verbesserung ergibt. Der Fall von mehrdimensionalen und diskrete Regressorvariablen wird mit Hilfe einer partiellen linearen Modell behandelt. Das Verfahren wird mithilfe der Arbeitsmarktanalysebeispiel erklärt. Hoch-dimensionale Zeitreihen, die nichtstationäre und eventuell periodische Verhalten zeigen, sind häufig in vielen Bereichen der Wissenschaft, zB Makroökonomie, Meteorologie, Medizin und Financial Engineering, getroffen. Der typische Modelierungsansatz ist die Modellierung von hochdimensionalen Zeitreihen in Zeit Ausbreitung der niedrig dimensionalen Zeitreihen und hoch-dimensionale zeitinvarianten Funktionen über dynamische Faktorenanalyse zu teilen. Wir schlagen ein zweistufiges Schätzverfahren. Im ersten Schritt entfernen wir den Langzeittrend der Zeitreihen durch Einbeziehung Zeitbasis von der Gruppe Lasso-Technik und wählen den Raumbasis mithilfe der funktionalen Hauptkomponentenanalyse aus. Wir zeigen die Eigenschaften dieser Schätzer unter den abhängigen Szenario. Im zweiten Schritt erhalten wir den trendbereinigten niedrig-dimensionalen stochastischen Prozess (stationär). / In many applications it is necessary to know the stochastic fluctuation of the maximal deviations of the nonparametric quantile estimates, e.g. for various parametric models check. Uniform confidence bands are therefore constructed for nonparametric quantile estimates of regression functions. The first method is based on the strong approximations of the empirical process and extreme value theory. The strong uniform consistency rate is also established under general conditions. The second method is based on the bootstrap resampling method. It is proved that the bootstrap approximation provides a substantial improvement. The case of multidimensional and discrete regressor variables is dealt with using a partial linear model. A labor market analysis is provided to illustrate the method. High dimensional time series which reveal nonstationary and possibly periodic behavior occur frequently in many fields of science, e.g. macroeconomics, meteorology, medicine and financial engineering. One of the common approach is to separate the modeling of high dimensional time series to time propagation of low dimensional time series and high dimensional time invariant functions via dynamic factor analysis. We propose a two-step estimation procedure. At the first step, we detrend the time series by incorporating time basis selected by the group Lasso-type technique and choose the space basis based on smoothed functional principal component analysis. We show properties of this estimator under the dependent scenario. At the second step, we obtain the detrended low dimensional stochastic process (stationary).

Purpose: We determined the indication, outcome and risk factors of single and multiple hematopoietic stem cell transplantation(s) (HSCT) in children and adolescents mostly with advanced disease. Methods: Forty-one out of 483 patients (8.5%; median age 9 years) diagnosed at the University of Leipzig with haematological and oncological diseases required HSCT from 1999 to 2011. Results: Patients had overall survival (OS) of 63±10% and 63±16%, event-free survival (EFS) of 57±10% and 42±16%, relapse incidence (RI) of 39±10% and 44±18% and non-relapse mor-tality (NRM) of 4±4% and 13±9% at 10-years after one or more HSCT for allogeneic and autologous HSCT, respectively. One patient in complete remission (CR)1 and five with advanced disease received two HSCT. Four of the six patients maintained/achieved CR for a median of 13 months. Three died of progression and one of NRM. Two patients had a third HSCT and one survived in CR +231 days after HSCT. Risk factors for OS and EFS were disease stage at HSCT and EBMT risk-score. Center (paediatric or JACIE accredited paediatric/adult) was not a determinant for survival. Conclusion: Paediatric single and multiple HSCT are important curative approaches for high-risk malignant diseases with low NRM. Efforts to reduce high RI remain the major aim.:Bibliographic description 3 Introduction: 4 Infections 6 Veno-occlusive disease (VOD) 7 Graft rejection 7 Graft-versus Host Disease (GvHD) 8 Non-relapse mortality (NRM) 9 Relapse of the underling disease 9 Indications for HSCT 10 HSCT in Children. 10 Research questions: 12 Publication 13 Discussion 22 Future developments 25 References 26 Abbreviations 28 Summary 29 Zusammenfassung 33 Erklärung über die eigenständige Abfassung der Arbeit 38 Curriculum vitae 39 Acknowledgement 42