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The aim of the thesis is a reconstruct the railway station Bystřice pod Hostýnem, so it would suit current and future traffic. The main purpose of the reconstruction is a design of platforms that meet requirements for persons with reduced mobility under applicable legislation.

Ce mémoire présente la conception d'un radar Ultra Large Bande à déclenchement optoélectronique dédié au rayonnement d'impulsions ultra-courtes dans une bande de travail comprise entre 300MHz et 3GHz pour réaliser des opérations de détection à courte et moyenne portée. A l'émission, ce radar est composé de plusieurs sources de rayonnement élémentaires constituées d'une antenne au sein de laquelle un générateur optoélectronique est intégré, d'un générateur de haute tension pulsée et d'un système commande optique. Des mesures de validation ont été menées pour s'assurer du bon fonctionnement d'une source. Cette association garantit une excellente synchronisation entre les sources et autorise un balayage électromagnétique autonome rapide en ajustant les fréquences de répétition (quelques dizaines de MHz) de chaque générateur de manière à décaler proportionnellement à l'angle visé, l'instant d'alimentation. A la réception, une antenne ou plusieurs antennes sont utilisées pour récupérer les signaux diffractés par les cibles et un traitement de signal est appliqué pour reconstruire l'image. Ce traitement spécifique permet de s'affranchir de la limite de détection en distance imposée par la fréquence de répétition en utilisant une association entre des calculs de corrélation et une déconvolution itérative. Un des vecteurs d'amélioration de la qualité de l'image a également été développé. Il concerne la génération de forme d'ondes et plus particulièrement le façonnage spectral par profilage temporel en utilisant un algorithme d'optimisation évolutionnaire. / This thesis presents the design of an Ultra Wide Band radar triggered by an optoelectronic generator which is dedicated to ultra short pulses radiation for short and medium range detection. The emitting part of this radar is based on transmitting array composed of several UWB antennas with an integrated photoswitch device triggered using optical pulses and a receiving UWB antenna. A specific signal processing method has been proposed and implemented for UWB optoelectronic radar involving autonomous beam scanning capability in order to overcome the limitation in the depth of detection encountered while using standard imaging algorithm. Indeed, this hybrid correlation/CLEAN algorithm considers the whole measured burst and finds the relevant information to rebuilt a radar map with a very good accuracy. In order to improve the radar map quality, the waveform generation technique has been discussed and, more precisely, the temporal shaping method to obtain specific spectrum using evolutionary algorithm.

The domain specific language P4 is a novel initiative which extends the Software-Defined Networking (SDN) paradigm by allowing for data plane programmability. Network virtualisation is a class of network technologies which can be used to abstract the addressing in a network, allowing multiple tenants to utilise the network resources while being agnostic to the underlying network and the other tenants. In other words, twins of tenants using the same addresses can co-exist on the same underlying network. If a twin is a distributed network, it may even be spread out across multiple sites which are connected to a common backbone. In this study, network virtualisation using P4 is evaluated with emphasis on scalability in terms of number of twins and sites. A set of potential network virtualisation technologies are identified and categorised. Based on this categorisation, two variations of network virtualisation are implemented on the P4 capable software switch BMv2 and the performance of both variations are evaluated against the non-P4 solution Linux bridge. Linux bridge was found to yield 451 times more useful bandwidth than the best performing P4 implementation on BMv2, while also learning MAC addresses faster and generating less traffic on the backbone. It is concluded that the performance of network virtualisation implemented and running on BMv2 is worse compared to the non-P4 solution Linux bridge.

The goal of the diploma thesis is the reconstruction of the Namest nad Oslavou railway station in aim to fulfill the requirements for the movement of persons with reduced mobility. It was necessary to design five platform edges with a height of the platform edge 550 mm above rail level in that context. Furthermore increased speed was designed in the main tracks. There was also included the design of reconstruction of drainage system of railway tracks.

No description available.

Part I . We explored the synthesis of a C -glycoside synthesis from L-fucose and malononitrile in the presence of a base catalyst. The reaction was much faster than the previously studied Henry condensation, and went further---to a double cyclization of 2:1 adduct with a novel dioxabicyclic structure. It provides a new route for the synthesis of chiral polysubstituted dihydropyrans and dihydropurans. A series of carbasugars was synthesized and tested for inhibitory activity towards fungal glycosidases from Aspergillus oryzae and Penicillium canescens . In order to reveal the dependence of inhibition on the alkyl group R, several derivatives with variable alkyl chain lengths were prepared and screened. Part II . Cyclohexane-based conformationally controlled ionophores, an emerging new class of molecular switches, provide a new and promising approach to allosteric systems with negative cooperativity. Protonation of trans -2-aminocyclohexanols was observed to cause dramatic conformational changes: due to an intramolecular hydrogen bond, a conformer with equatorial position of ammonio- and hydroxy-groups becomes predominant. This signal is mechanically transmitted by the structure of the molecule, inducing a conformational change in the second site and decreasing its affinity for an appropriate guest. Thus, these structures can serve as powerful conformational pH-triggers. The trans -2-aminocyclohexanol moiety has been used for pH-triggered conformational switching of crown ethers and podands, and their complexes with metal ions. The variation of the NR 2 group allows broad tuning of the conformational equilibrium, and thus tuning of the complexing ability of these allosteric ionophores. Heterotropic allosteric systems with high negative cooperativity may find many applications, such as membrane transport and drug delivery.

Melamine and cyanuric acid are widely used in industry and in scientific research. The mixture of melamine and cyanuric acid can form a hydrogen-bonded network structure which has been used as a surface template in supramolecular chemistry. In this work, the thermochemical properties of melamine and cyanuric acid were characterized using mass spectrometry measurements and computational studies. The proton affinity and the gas-phase acidity were determined with the application of the extended Cooks kinetic method. A triple-quadrupole mass spectrometer equipped with an electrospray source was employed for this study. For melamine, the proton affinity, the gas-phase basicity, and the protonation entropy were determined to be 226.2 ± 2.0 kcal/mol, 218.4 ± 2.0 kcal/mol and 26.2 ± 2.0 cal/mol K, respectively. For cyanuric acid, the deprotonation enthalpy, the gas-phase acidity, and the deprotonation entropy were determined to be 330.7 ± 2.0 kcal/mol, 322.9 ± 2.0 kcal/mol and 26.1 ± 2.0 cal/mol K, respectively. The geometries and energetics of melamine, cyanuric acid, and related molecules/ions were calculated at the B3LYP/6-31+G(d) level of theory. The theoretical proton affinity and deprotonation enthalpy were calculated using the corresponding isodesmic proton transfer reactions. The computationally predicted proton affinity of melamine (225.9 kcal/mol) and gas-phase deprotonation enthalpy of cyanuric acid (328.4 kcal/mol) were in good agreement with the experimental results. Melamine is best represented as the imide-like triazine-triamine form and the triazine nitrogen is more basic than the amino group nitrogen. Cyanuric acid is best represented as the keto-like tautomer and the N-H group is the most likely proton donor. Cyclohexane-based molecular switches have been of great interest in recent years. This work focused on the investigations of the thermochemical properties related to the switching process. A group of cyclohexane-based model compounds were selected for this study. The model compounds included trans -2-aminocyclohexanol, trans -4-aminocyclohexanol and trans -2-dimethylaminocyclohexanol. The proton affinities of the compounds were determined using the extended Cooks kinetic method. The values obtained were 238.5 ± 2.0 kcal/mol ( trans -2-dimethylaminocyclohexanol), 225.5 ± 2.0 kcal/mol ( trans -2-aminocyclohexanol) and 220.4 ± 2.0 kcal/mol ( trans -4-aminocyclohexanol). Various molecular structures related to the model compounds and the switching molecules were calculated at the B3LYP/6-31+G(d) level of theory. The theoretical proton affinities of all the molecules investigated were also calculated at the same level of theory using corresponding isodesmic reactions. The results show that the proton affinities decrease as the relative positions of amino and alcohol groups change from ortho to meta to para . The stronger proton affinity of the ortho isomer may be due to the efficient intramolecular hydrogen bonding in the protonated form. The proton affinity of trans -2-dimethylaminocyclohexanol is stronger than that of trans -2-aminocyclohexanol by about 13 kcal/mol. Substitution of hydrogen atoms by methyl groups at nitrogen promotes the intramolecular hydrogen bonding between the amino group and the hydroxyl group upon protonation. This, in turn, may enhance the proton affinity of methylated molecule. Computational studies also show interesting trends for stabilities and proton affinities of the different structures. These data may be useful as a guide for designing efficient conformational switches.

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No description available.