This theses aims to propose two alternatives of optimised construction procedures for the reconstruction of the railway station Mikulášovice dolní nádraží. The reconstruction is based on the design provided by Metroprojekt Praha a.s. Each alternative describes suitable mechanization, coordination of works, including needed number of workers, coordination of the works and the total implentation cost analysis. As the thesis deals with reconstruction, it also considers substitute transportation plan. The details are summarized in extensive schedules. The two alernative are compared and evaluated.

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Schalentragwerke sind aufgrund ihres vorteilhaften Lastabtragverhaltens im Membranzustand sehr geeignet für die Herstellung leichter Tragwerke. Der Schwerpunkt dieses Projekts liegt auf der Entwicklung einer geeigneten numerischen Methode, um möglichst effizient statische und dynamische Berechnungen durchzuführen und damit den Entwurf zu erleichtern. Für Entwurf und Analyse wird eine neuartige Kombination von Substrukturtechnik und Modellreduktion eingesetzt, um den notwendigen Rechenaufwand zu minimieren. [Aus: Einleitung] / Shell structures are very suitable for the construction of lightweight structures, especially because of the load bearing behaviour in the membrane state. Based on this concept, the main focus of this project is to develop suitable numerical methods to carry out the static and dynamic analysis efficiently, with the target of simplifying the design. For the design and analysis, a new methodology has been developed which couples substructuring and model order reduction. This allows to reduce the degrees of freedom of the system as well as the computational ef ort signif cantly. [Off: Introduction]

Selection and genetic drift are often competing forces in shaping genetic structure in populations. Genetic drift will often effectively cancel out the effect of selection when population sizes are small, such as in colonizing island populations. On a small island in the Skeppsvik Archipelago in northern Sweden, a newly founded population of Silene dioica has been monitored since it first established around 1993. Though inhabiting an area of merely 173 m2, the population has been shown to exhibit a genetically differentiated patch structure where closely related individuals are tightly grouped, distanced from other family groups. In this study, the effect of selection was evaluated as compared to that of genetic drift. Variation in phenotypic traits in flowers, leaves and stalks were compared to that of neutral markers, in the form of PST and FST measures, to assess a measure of what proportion of differentiation among patches in phenotypic traits could not be attributed to genetic drift. Males and females were analysed separately to obtain measures of sex specific selection. Signs of divergent and stabilizing selection were found in several traits in both males and females despite the small spatial scale and short time since colonization. Further analysis is needed to assess explanations for trait divergence among patches and direction of selection.

The advances in computational and experimental modeling in the area of structural mechanics have stimulated research in a class of hybrid problems that require both of these modeling capabilities to be combined to achieve certain objectives. Real-time substructure (RTS) testing, structural system identification (SSI) and active control techniques fall in the category of hybrid problems that need efficient tools in both computational and experimental phases for their successful implementation. RTS is a hybrid testing method, which aims to overcome the scaling problems associated with the conventional dynamic testing methods (such as shake table test, effective force test and pseudo dynamic test) by testing the critical part of the structure experimentally with minimum compromise on spatio-temporal scaling, while modeling the remaining part numerically. The problem of SSI constitutes an important component within the broader framework of problems of structural health monitoring where, based on the in-situ measurements on the loading and a subset of critical responses of the structure, the system parameters are estimated with a view to detecting damage/degradation. Active control techniques are employed to maintain the functionality of important structures, especially under extreme dynamic loading. The work reported in the present thesis contributes to the areas of RTS, SSI and active control of nonlinear systems, the main focus being the computational aspects, i.e., in developing numerical strategies to address some of the unsolved issues, although limited efforts have also been made to undertake laboratory experimental investigations in the area of nonlinear SSI. The thesis is organized into seven chapters and five appendices. The first chapter contains an overview of the state of the art techniques in dynamic testing, SSI and structural control. The topics covered include effective force test, pseudo dynamic test, RTS test, time and frequency domain methods of nonlinear system identification, dynamic state estimation techniques with emphasis on particle filters, Rao-Blackwellization, structural control methods, control algorithms and active control of nonlinear systems. The review identifies a set of open problems that are subsequently addressed, to an extent, in the thesis. Chapter 2 focuses on the development of a time domain coupling technique, involving combined computational and experimental modeling, for vibration analysis of structures built-up of linear/nonlinear substructures. The numerical and experimental substructures are allowed to interact in real-time. The equation of motion of the numerical substructure is integrated using a step-by-step procedure that is formulated in the state space. For systems with nonlinear substructures, a multi-step transversal linearization method is used to integrate the equations of motion; and, a multi-step extrapolation scheme, based on the reproducing kernel particle method, is employed to handle the time delays that arise while accounting for the interaction between the substructures. Numerical illustrations on a few low dimensional vibrating structures are presented and these examples are fashioned after problems of seismic qualification testing of engineering structures using RTS testing techniques. The concept of substructuring is extended in Chapter 3 for implementing Rao-Blackwellization, a technique of combining particle filters with analytical computation through Kalman filters, for state and parameter estimations of a class of nonlinear dynamical systems with additive Gaussian process/observation noises. The strategy is based on decomposing the system to be estimated into mutually coupled linear and nonlinear substructures and then putting in place a rational framework to account for coupling between the substructures. While particle filters are applied to the nonlinear substructures, estimation of linear substructures proceeds using a bank of Kalman filters. Numerical illustrations for state/parameter estimations of a few linear and nonlinear oscillators with noise in both the process and measurements are provided to demonstrate the potential of the Rao-Blackwellized particle filter (RBPF) with substructuring. In Chapter 4, the concept of Rao-Blackwellization is extended to handle more general nonlinear systems, using two different schemes of linearization. A semi-analytical filter and a conditionally linearized filter, within the framework of Monte Carlo simulations, are proposed for state and parameter estimations of nonlinear dynamical systems with additively Gaussian process/observation noises. The first filter uses a local linearization of the nonlinear drift fields in the process/observation equations based on explicit Ito-Taylor expansions to transform the given nonlinear system into a family of locally linearized systems. Using the most recent observation, conditionally Gaussian posterior density functions of the linearized systems are analytically obtained through the Kalman filter. In the second filter, the marginalized posterior distribution of an appropriately chosen subset of the state vector is obtained using a particle filter. Samples of these marginalized states are then used to construct a family of conditionally linearized system of equations to obtain the posterior distribution of the states using a bank of Kalman filters. The potential of the proposed filters in state/parameter estimations is demonstrated through numerical illustrations on a few nonlinear oscillators. The problem of active control of nonlinear structural dynamical systems, in the presence of both process and measurement noises, is considered in Chapter 5. The focus of the study is on the exploitability of particle filters for state estimation in feedback control algorithms for nonlinear structures, when a limited number of noisy output measurements are available. The control design is done using the state dependent Riccati equation (SDRE) method. The Bayesian bootstrap filter and another based on sequential importance sampling are employed for state estimation. Numerical illustrations are provided for a few typically nonlinear oscillators of interest in structural engineering. The experimental validation of the RBPF using substructuring (developed in Chapter 3) and the conditionally linearized Monte Carlo filter (developed in Chapter 4), for parameter estimation, is reported in Chapter 6. Measured data available through laboratory experiments on simple building frame models subjected to harmonic base motions is processed using the proposed algorithms to identify the unknown parameters of the model. A brief summary of the contributions made in this thesis, together with a few suggestions for future research, are presented in Chapter 7. Appendix A provides an account of the multi-step transversal linearization method. The derivation of the reproducing kernel shape functions are presented in Appendix B. Appendix C provides the details of the stochastic Taylor expansion and derivation of the covariance structure of Gaussian MSI-s. The performance of a particle filtering algorithm (bootstrap filter) and Kalman filter in the state estimation of a linear system is provided in Appendix D and Appendix E contains the theoretical details of the Rao-Blackwellized particle filter.

The subject of the master’s thesis is to design a reconstruction of the Letovice railway station for access for persons with reduced mobility and orientation. The thesis deals with adjustment to the railway superstructure, substructure and drainage system of the station. Part of the thesis is explore the possibility of building a new railway stop.

The theme of this diploma thesis deals with comparing technologies of reconstruction of the railway track No. 2 between railway stations Hranice na Morave and Hustopece nad Becvou in km 7,792 393 – 7,967 592 and in km 8,725 000 – 14,988 677. The aim of the thesis is to design several variants for the reconstruction of the substructure and superstructure, and then compare these variants. This thesis deals with technologies with removal of the track length and with technologies without removal of the track length. Part of the thesis is a description of used technologies and machines connected with them.

The task of the thesis is to propose the third track in track section Blansko - Rájec-Jestřebí and increasing line speed with maximum use of existing track body and grounds of SŽDC, s.o. Next is the design of the reconstruction of all engineering objects (bridges, runoffs, railway crossings and platforms). Additioning of the third track will cause extensive structural modifications at railway stations Blansko and Rájec-Jestřebí. Within the building will be verified construction of new railway stop Spešov.

The diploma thesis compiles working method of construction works at Pačejov railway station and in adjacent double-track section in the range of working procedures from SP0 to SP3a. The thesis compares the time and economical aspects of individual technologies and entire construction methods. The thesis includes description of rail and non-rail mechanization.

The master thesis "Upgrading of Jindřichov na Moravě and Branná Railway Stations" deals with designing new platforms that are suitable for people with reduced mobility in accordance with applicable laws and standards. Platforms with the platform edge height of 550 millimetres above the top of rail were designed. The speed limit was increased from the original 40 km/h up to 50 km/h. Moreover, the thesis design reconstruction of railway superstructure and railway substructure and deal with the drainage system.