Im Vergleich zu Stahlseilen haben hochfeste Faserseile vorteilhafte Eigenschaften. Insbesondere die bei gleicher Bruchlast um den Faktor 7 bis 10 reduzierte Eigenmasse ermöglicht neue Anwendungen. Die Nachteile von hochfesten Faserseilen gegenüber Stahlseilen , wie beispielsweise Druckempfindlichkeit und Empfindlichkeit gegenüber Wärmeeintrag , behindern den Einsatz von hochfesten Faserseilen in zahlreichen Anwendungsgebieten. Mit der vorliegenden Arbeit soll dieses Problem behoben werden. Dazu wurden die Grundlagen zur Auslegung einer neuen Winde für hochfeste Faserseile , welche die Nachteile dieser Zugmittel kompensiert, erarbeitet. Diese sogenannte Hüllandruckwinde vereint die Eigenschaften von hoher Treibkraft und Seilschonung auf kompaktem Bauraum. Eine Hüllandruckwinde ist eine Treibscheibenwinde, bei der das Seil durch ein umlaufendes, sogenanntes Hüllandruckelement in eine seilschonende Rundrille gedrückt wird. Das Hüllandruckelement kann als Zahnriemen mit Rundrille ausgeführt werden. Sowohl Treibscheibe als auch Hüllandruckelement sind angetrieben. Zur Auslegung von Hüllandruckwinden ist die Kenntnis der Treibkraft und des Systemverhaltens erforderlich. Bei der Überprüfung des Stands der Forschung auf geeignete Treibkraftmodelle stellte sich heraus, dass bislang kein geeignetes Modell existierte. Somit erfolgte die Erarbeitung des sogenannten verallgemeinerten nichtlinearen Modells zur Beschreibung der Treibkraft von Hüllandruckwinden. Dieses wurde validiert und mit einem Benchmark-Modell des Stands der Forschung verglichen. Das verallgemeinerte nichtlineare Modell weist im Vergleich zum Benchmark-Modell für den Zustand Haften einen im Durchschnitt 70 % und für den Zustand Gleiten einen im Durchschnitt 36 % niedrigeren mittleren relativen Fehler auf. Das verallgemeinerte nichtlineare Modell sagt in Bezug zu den Messdaten im Durchschnitt einen um 3,5 % erhöhten Wert vorher. Außerdem wurde das Systemverhalten von Hüllandruckwinden untersucht. Dabei konnte nachgewiesen werden, dass das Verhältnis der Winkelgeschwindigkeiten zwischen Treibscheibe und Hüllandrucklement im Bereich des Umschlingungswinkels des Hüllandruckelements auf dem Seil keinen Einfluss auf die Treibkraft hat. In Verspannversuchen mit einer Last unterhalb der Treibkraft konnten ein um 800 % überhöhtes virtuelles Antriebsdrehmoment des Hüllandruckelements und ein um 538 % überhöhtes Antriebsdrehmoment der Treibscheibe gemessen werden. Als Abhilfemaßnahme für diese überhöhten Antriebsdrehmomente erfolgte die Vorstellung eines lastabhängigen Vorspannmechanismus des Hüllandruckelements, welcher in der Nullserie der Hüllandruckwinde „HERO 1000“ angewendet wird. Aus der Gesamtheit der Erkenntnisse wurden Gestaltungshinweise für Hüllandruckwinden abgeleitet.:Kurzfassung VII Abstract IX 1 Einleitung 11 1.1 Problemstellung und Motivation 11 1.2 Zielsetzung und Forschungsfragen 13 1.3 Aufbau der Arbeit 15 2 Stand der Technik 17 2.1 Definitionen und Erläuterungen 17 2.2 Hochfeste Faserseile 21 2.3 Ablegereife und Zustandsüberwachung 23 2.4 Trommelwinden 25 2.5 Durchlaufwinden 27 2.5.1 Einfach umschlungene Treibscheibenwinden mit glatter Rille 28 2.5.2 Einfach umschlungene Treibscheibenwinden mit profilierten Rillen 30 2.5.3 Mehrfach umschlungene, mehrrillige Treibscheibenwinden 31 2.5.4 Spillwinden 35 2.6 Bandscheibenabzüge 37 3 Stand der Forschung 43 4 Mathematische Modellierung 51 4.1 Betriebssituationen 51 4.2 Vereinfachungen 52 4.3 Festlegungen 55 4.4 Modellierung der Treibkraft 56 4.4.1 Herleitung 56 4.4.2 Lösungen Treibkraftfall C 62 4.4.3 Lösungen Treibkraftfall A 63 4.4.4 Lösungen Treibkraftfall B 64 4.4.5 Lösung Treibscheibenbetrieb ohne HAE 65 4.5 Modellierung der Synchronisation 65 5 Experimentelle Untersuchungen 69 5.1 Versuchsstand 69 5.1.1 Parameter 69 5.1.2 Mechanischer Aufbau 72 5.1.3 Steuerung des Versuchsablaufs 75 5.1.4 Kalibrierung der Frequenzumrichter 76 5.1.5 Erfassung der Messgrößen 78 5.1.6 Auswertung der Messergebnisse 79 5.2 Auswahl der Materialpaarungen 84 5.3 Versuchsplanung 86 5.3.1 Treibkraft 87 5.3.2 Systemverhalten 90 5.4 Versuchsdurchführung 91 5.4.1 Treibkraft 91 5.4.2 Systemverhalten 95 6 Diskussion der Ergebnisse 97 6.1 Vorgehensweise 98 6.2 Treibkraft 99 6.2.1 Treibscheibenbetrieb ohne HAE 99 6.2.2 Treibkraftfall A 109 6.2.3 Treibkraftfall B 114 6.2.4 Treibkraftfall C 120 6.2.5 Kritische Betrachtung des Treibkraftmodells 130 6.3 Systemverhalten 132 6.3.1 Verspannversuche 132 6.3.2 Synchronisationsversuche 139 6.3.3 Fazit Systemverhalten 143 6.4 Gestaltungshinweise für HAW 144 7 Zusammenfassung und Ausblick 147 7.1 Zusammenfassung 147 7.2 Ausblick 150 Abkürzungen 153 Symbole 155 Abbildungsverzeichnis 161 Tabellenverzeichnis 165 Literaturverzeichnis 169 Anlagenverzeichnis 182 / Compared to steel ropes, high-strength fibre ropes have advantageous properties. In particular, the reduction in dead weight by a factor of 7 to 10 for the same breaking load makes new applications possible. The disadvantages of high-strength fibre ropes compared to steel ropes, such as pressure sensitivity and sensitivity to heat input, hinder the use of high-strength fibre ropes in numerous areas of application. The present work is intended to eliminate this problem. For this purpose, the basic principles for the development of a new winch for high-strength fibre ropes, which compensates for the disadvantages of high-strength fibre ropes, were worked out. This so-called belt wrap capstan combines the properties of high driving force and rope protection in a compact design. A belt wrap capstan is a traction sheave winch in which the rope is pressed into a round groove by a so-called belt wrap capstan. The enveloping pressure element can be designed as a toothed belt with a round groove. Both the traction sheave and the enveloping pressure element are driven. The design of belt wrap capstans requires knowledge of the driving force and the system behaviour. When reviewing the state of research for suitable driving force models, it was found that no suitable model existed so far. Therefore, a so-called generalised non-linear model was developed to describe the driving force of belt wrap capstans. This was validated and compared with a benchmark model of the state of the art. Compared to the benchmark model, the generalised nonlinear model has a 70 % lower mean relative error for the sticking condition and a 36 % lower mean relative error for the sliding condition. The generalised non-linear model predicts a 3.5 % higher value on average. The system behaviour of belt wrap capstans was also investigated. It was demonstrated that the ratio of angular velocities between the drive sheave and the enveloping pressure element within the wrap angle of the enveloping pressure element on the rope has no influence on the driving force. In tensioning tests with a load below the driving force, an 800 % excessive virtual driving torque of the sheath pressure element and a 538 % excessive driving torque of the traction sheave could be measured. As a remedy for the tensioning, a load-dependent pretensioning mechanism of the belt wrap capstan was presented, which is used in the zero series of the belt wrap capstan 'HERO 1000'. Design recommendations for belt wrap capstans were derived from all the findings.:Kurzfassung VII Abstract IX 1 Einleitung 11 1.1 Problemstellung und Motivation 11 1.2 Zielsetzung und Forschungsfragen 13 1.3 Aufbau der Arbeit 15 2 Stand der Technik 17 2.1 Definitionen und Erläuterungen 17 2.2 Hochfeste Faserseile 21 2.3 Ablegereife und Zustandsüberwachung 23 2.4 Trommelwinden 25 2.5 Durchlaufwinden 27 2.5.1 Einfach umschlungene Treibscheibenwinden mit glatter Rille 28 2.5.2 Einfach umschlungene Treibscheibenwinden mit profilierten Rillen 30 2.5.3 Mehrfach umschlungene, mehrrillige Treibscheibenwinden 31 2.5.4 Spillwinden 35 2.6 Bandscheibenabzüge 37 3 Stand der Forschung 43 4 Mathematische Modellierung 51 4.1 Betriebssituationen 51 4.2 Vereinfachungen 52 4.3 Festlegungen 55 4.4 Modellierung der Treibkraft 56 4.4.1 Herleitung 56 4.4.2 Lösungen Treibkraftfall C 62 4.4.3 Lösungen Treibkraftfall A 63 4.4.4 Lösungen Treibkraftfall B 64 4.4.5 Lösung Treibscheibenbetrieb ohne HAE 65 4.5 Modellierung der Synchronisation 65 5 Experimentelle Untersuchungen 69 5.1 Versuchsstand 69 5.1.1 Parameter 69 5.1.2 Mechanischer Aufbau 72 5.1.3 Steuerung des Versuchsablaufs 75 5.1.4 Kalibrierung der Frequenzumrichter 76 5.1.5 Erfassung der Messgrößen 78 5.1.6 Auswertung der Messergebnisse 79 5.2 Auswahl der Materialpaarungen 84 5.3 Versuchsplanung 86 5.3.1 Treibkraft 87 5.3.2 Systemverhalten 90 5.4 Versuchsdurchführung 91 5.4.1 Treibkraft 91 5.4.2 Systemverhalten 95 6 Diskussion der Ergebnisse 97 6.1 Vorgehensweise 98 6.2 Treibkraft 99 6.2.1 Treibscheibenbetrieb ohne HAE 99 6.2.2 Treibkraftfall A 109 6.2.3 Treibkraftfall B 114 6.2.4 Treibkraftfall C 120 6.2.5 Kritische Betrachtung des Treibkraftmodells 130 6.3 Systemverhalten 132 6.3.1 Verspannversuche 132 6.3.2 Synchronisationsversuche 139 6.3.3 Fazit Systemverhalten 143 6.4 Gestaltungshinweise für HAW 144 7 Zusammenfassung und Ausblick 147 7.1 Zusammenfassung 147 7.2 Ausblick 150 Abkürzungen 153 Symbole 155 Abbildungsverzeichnis 161 Tabellenverzeichnis 165 Literaturverzeichnis 169 Anlagenverzeichnis 182

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p, li { white-space: pre-wrap; } The main goal of this work is to analyze the creation of the composite compiler. Composite compiler is in this case a szstem, which consists of more cooperating parts. My compiler is special, because its syntactic analyser consists of two parts. The work is focused on the construction of the parsers parts, on its cooperation and comunication. I will trys to scatch the teoretical backgroun of this solution. This is to be done by gramatical systems. Then I~will try to justify whether or not it is neccesary and suitable to create such a kind of parser. Last but not least I~will analyse the language, whose syntactic analyser is to be implemented by the chosen method.

p, li { white-space: pre-wrap; } p, li { white-space: pre-wrap; } This thesis deals with text ciphering. The presented paper describes at first basic theoretical background of cryptology and basic distribution of cryptographic algorithms. Then it describes a brief history of encryption from beginning to present. Theoretical description of ciphering methods and its implementation details are discussed here. All basic types of conventional encryption algorithms and also some modern ciphering methods are included; these are substitution, transposition, steganographic or combinations encryption systems. The result of this thesis is the library of algorithms for text ciphering in Java with a sample application, which demonstrates its funcionality.

The next generation wireless networks i.e. 5G aim to provide multi-Gbps data traffic, in order to satisfy the increasing demand for high-definition video, among other high data rate services, as well as the exponential growth in mobile subscribers. To achieve this dramatic increase in data rates, current research is focused on improving the capacity of current 4G network standards, based on Long Term Evolution (LTE), before radical changes are exploited which could include acquiring additional/new spectrum. The LTE network has a reuse factor of one; hence neighbouring cells/sectors use the same spectrum, therefore making the cell edge users vulnerable to inter-cell interference. In addition, wireless transmission is commonly hindered by fading and pathloss. In this direction, this thesis focuses on improving the performance of cell edge users in LTE and LTE-Advanced (LTE-A) networks by initially implementing a new Coordinated Multi-Point (CoMP) algorithm to mitigate cell edge user interference. Subsequently Device-to-Device (D2D) communication is investigated as the enabling technology for maximising Resource Block (RB) utilisation in current 4G and emerging 5G networks. It is demonstrated that the application, as an extension to the above, of novel power control algorithms, to reduce the required D2D TX power, and multihop transmission for relaying D2D traffic, can further enhance network performance. To be able to develop the aforementioned technologies and evaluate the performance of new algorithms in emerging network scenarios, a beyond-the-state-of-the-art LTE system-level simulator (SLS) was implemented. The new simulator includes Multiple-Input Multiple-Output (MIMO) antenna functionalities, comprehensive channel models (such as Wireless World initiative New Radio II i.e. WINNER II) and adaptive modulation and coding schemes to accurately emulate the LTE and LTE-A network standards. Additionally, a novel interference modelling scheme using the 'wrap around' technique was proposed and implemented that maintained the topology of flat surfaced maps, allowing for use with cell planning tools while obtaining accurate and timely results in the SLS compared to the few existing platforms. For the proposed CoMP algorithm, the adaptive beamforming technique was employed to reduce interference on the cell edge UEs by applying Coordinated Scheduling (CoSH) between cooperating cells. Simulation results show up to 2-fold improvement in terms of throughput, and also shows SINR gain for the cell edge UEs in the cooperating cells. Furthermore, D2D communication underlaying the LTE network (and future generation of wireless networks) was investigated. The technology exploits the proximity of users in a network to achieve higher data rates with maximum RB utilisation (as the technology reuses the cellular RB simultaneously), while taking some load off the Evolved Node B (eNB) i.e. by direct communication between User Equipment (UE). Simulation results show that the proximity and transmission power of D2D transmission yields high performance gains for a D2D receiver, which was demonstrated to be better than that of cellular UEs with better channel conditions or in close proximity to the eNB in the network. The impact of interference from the simultaneous transmission however impedes the achievable data rates of cellular UEs in the network, especially at the cell edge. Thus, a power control algorithm was proposed to mitigate the impact of interference in the hybrid network (network consisting of both cellular and D2D UEs). It was implemented by setting a minimum SINR threshold so that the cellular UEs achieve a minimum performance, and equally a maximum SINR threshold to establish fairness for the D2D transmission as well. Simulation results show an increase in the cell edge throughput and notable improvement in the overall SINR distribution of UEs in the hybrid network. Additionally, multihop transmission for D2D UEs was investigated in the hybrid network: traditionally, the scheme is implemented to relay cellular traffic in a homogenous network. Contrary to most current studies where D2D UEs are employed to relay cellular traffic, the use of idle nodes to relay D2D traffic was implemented uniquely in this thesis. Simulation results show improvement in D2D receiver throughput with multihop transmission, which was significantly better than that of the same UEs performance with equivalent distance between the D2D pair when using single hop transmission.

Use of soil retaining walls for roads, embankments and bridges is increasing with time and reinforced soil retaining walls are found to be very efficient even under critical conditions compared to unreinforced walls. They offer competitive solutions to earth retaining problems associated with less space and more loads posed by tremendous growth in infrastructure, in addition to the advantages in ease and cost of construction compared to conventional retaining wall systems. The study of seismic performance of reinforced soil retaining walls is receiving much attention in the light of lessons learned from past failures of conventional retaining walls. Laboratory model studies on these walls under controlled seismic loading conditions help to understand better how these walls actually behave during earthquakes. The objective of the present study is to investigate the seismic response of geosynthetic reinforced soil wall models through shaking table tests. To achieve this, wrap faced and rigid faced reinforced soil retaining walls of size 750 × 500 mm in plan and 600 mm height are built in rigid and flexible containers and tested under controlled dynamic conditions using a uni-axial shaking table. The effects of frequency and acceleration of the base motion, surcharge pressure on the crest, number of reinforcing layers, container boundary, wall structure and reinforcement layout on the seismic performance of the retaining walls are studied through systematic series of shaking table tests. Results are analyzed to understand the effect of each of the considered parameters on the face displacements, acceleration amplifications and soil pressures on facing at different elevations of the walls. A numerical model is developed to simulate the shaking table tests on wrap faced reinforced soil walls using a computer program FLAC (Fast Lagrangian Analysis of Continua). The experimental data are used to validate the numerical model and parametric studies are carried out on 6 m height full-scale wall using this model. Thus, the study deals with the shaking table tests, dynamic response of reinforced walls and their numerical simulation. The thesis presents detailed description of various features and various parts of the shaking table facility along with the instrumentation and model containers. Methodology adopted for the construction of reinforced soil model walls and testing procedures are briefly described. Scaling and stability issues related to the model wall size and reinforcement strength are also discussed. From the study, it is observed that the displacements are decreasing with the increase in relative density of backfill, increase in surcharge pressure and increase in number of reinforcing layers; In general, accelerations are amplified to the most at the top of the wall; Behaviour of model walls is sensitive to model container boundary. The frequency content is very important parameter affecting the model response. Further, it is noticed that the face displacements are significantly affected by all of the above parameters, while the accelerations are less sensitive to reinforcement parameters. Even very low strength geonet and geotextile are able to reduce the displacements by 75% compared to unreinforced wall. The strain levels in the reinforcing elements are observed to be very low, in the order of ±150 micro strains. A random dynamic event is also used in one of the model tests and the resulted accelerations and displacements are presented. Numerical parametric studies provided important insight into the behaviour of wrap faced walls under various seismic loading conditions and variation in physical parameters.

The main complication of aortocoronary reconstruction with vein grafts is restenosis in the course of time. The aim was to assess the effect of a periadventitial polyester system releasing sirolimus on intimal hyperplasia of autologous grafts. The controlled-release system comprises a polyester mesh coated with a sirolimus-eluting copolymer of L lactic acid and ε-caprolactone system designed to be wrapped around an autologous venous graft during its implantation. In vitro sirolimus release and its effects on smooth muscle and endothelial cells were assessed. In vitro, the copolymer-coated polyester mesh released sirolimus over a period of 6 weeks. Mesh-eluted sirolimus inhibited the growth of smooth muscle and endothelial cells in seven-day in vitro experiments. After seven days of sirolimus release from the mesh, smooth muscle and endothelial cell counts decreased by 29% and 75%, respectively, with the cells maintaining high viability. We implanted v. jugularis ext. into a. carotis communis in rabbits. The vein graft was either intact, or was wrapped with a pure polyester mesh, or with a sirolimus-releasing mesh. Three and six weeks after surgery, the veins were subjected to standard histological staining and the thicknesses of the tunica intima, the media and the intima-media complex were...

The objective of this thesis research is to improve our understanding of the flow obstacle effect on heat transfer at supercritical and high subcritical pressures by experimentally studying the effect of different obstacles on heat transfer in two vertical upward-flow test sections: a 3-rod bundle and an 8 mm ID tube. The heat transfer measurements cover the region of interest of the Canadian Super-critical Water Cooled Reactor (SCWR). A thorough analysis of the obstacle effect on supercritical heat transfer (SCHT) was performed. In the 3-rod bundle, two types of obstacles were employed: wire wraps and low-impact grid spacers. Wire wraps were found to be more effective than grid spacers to enhance the SCHT. In the tubular test section, obstacles appeared to suppress the heat transfer deterioration (HTD) or decrease its severity; obstacles also generally enhanced the SCHT both in the liquid-like and the gas- like region. The experiment in the tubular test section revealed that, at certain flow conditions (low mass flux, low inlet subcooling), flow obstacles can have an adverse impact on the SCHT. A criterion to predict the onset of this adverse effect was developed. At high subcritical pressures, obstacles increased the CHF and reduced the maximum post-CHF temperature. A comparison of the experimental data with prediction methods for the SCHT, single phase heat transfer, CHF and post-dryout heat transfer was performed. Lastly, a new correlation to predict the enhancement in SCHT due to obstacles was developed for heat transfer in the liquid-like and gas-like regions.

This thesis is focused on assessing the impact of retrofitting dielectric All Dielectric Self-Supporting Cable (ADSS) to existing MV overhead line. This type of optical cable is a means of future strengthening of the communication infrastructure of the distribution network. However, its mechanical properties are significantly different from the properties ACSR cable, due to which its installation can be problematic in terms of meeting the requirements of the PNE 33 3301 standard. In practical part, this work deals with the design of the ADSS installation on the existing MV line and the determination of its impact based on the assessment of the results of this design.

The main complication of aortocoronary reconstruction with vein grafts is restenosis in the course of time. The aim was to assess the effect of a periadventitial polyester system releasing sirolimus on intimal hyperplasia of autologous grafts. The controlled-release system comprises a polyester mesh coated with a sirolimus-eluting copolymer of L lactic acid and ε-caprolactone system designed to be wrapped around an autologous venous graft during its implantation. In vitro sirolimus release and its effects on smooth muscle and endothelial cells were assessed. In vitro, the copolymer-coated polyester mesh released sirolimus over a period of 6 weeks. Mesh-eluted sirolimus inhibited the growth of smooth muscle and endothelial cells in seven-day in vitro experiments. After seven days of sirolimus release from the mesh, smooth muscle and endothelial cell counts decreased by 29% and 75%, respectively, with the cells maintaining high viability. We implanted v. jugularis ext. into a. carotis communis in rabbits. The vein graft was either intact, or was wrapped with a pure polyester mesh, or with a sirolimus-releasing mesh. Three and six weeks after surgery, the veins were subjected to standard histological staining and the thicknesses of the tunica intima, the media and the intima-media complex were...