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vi, 110 leaves : ill. ; 30 cm / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Applied Mathematics, 1980

Thesis (Ph.D.) -- University of Adelaide, Department of Applied Mathematics, 1980.

Ziel dieser Studie war es, die längerfristige Auswirkung der Taschenspül-lösungen 0,9% NaCl (n=18), 0,12% Chlorhexidindigluconat (n=17) und Povidon-Jod (n=16) auf klinische und mikrobiologische Variablen bei 51 Patienten mit generalisierter moderater chronischer Parodontitis während des full mouth SRP zu untersuchen. Die subgingivale Irrigation der behandelten parodontalen Taschen wurde randomisiert durchgeführt. Vor SRP, nach 3 und nach 12 Monaten erfolgte die klinische Diagnostik (PD, BOP, AL) mittels 6-Punktmessung. Subgingivaler Biofilm wurde an vier Zähnen mit einer Sondierungstiefe von 4-6 mm zur quantitativen mikrobiologischen real time PCR-Analyse von Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia und Treponema denticola entnommen. PD nahm in allen Gruppen signifikant ab (p<0,001–p=0,002), CHX wirkte dabei nach 3 Monaten signifikant besser als NaCl (p=0,041). AL war in allen Gruppen nach 3 Monaten signifikant verbessert, nach 12 Monaten nur in der CHX- und Povidon-Jod-Gruppe (p<0,001–p=0,044) ohne Unterschiede zwischen den Gruppen. BOP war bei allen signifikant verringert (p<0,001–p=0,002) ohne Unterschiede zwischen den Gruppen. Die Gesamtkeimzahl von A.a. (p=0,045) und von P.g. (p=0,002) war nach 12 Monaten und von T.f. nach 3 (p=0,021) und zwischen 3 und 12 Monaten (p=0,011) für Povidon-Jod signifikant reduziert. Für P.g. wurde eine signifikante Reduktion der positiven Proben in der Povidon-Jod-Gruppe nach 3 (p=0,017) und nach 12 Monaten (p=0,001) festgestellt. Bei T.d. lag keine signifikante Veränderung vor. Signifikante Unterschiede lagen zur Baseline-Untersuchung bei A.a. zwischen der CHX- und der Povidon-Jod-Gruppe (p=0,038) und bei P.g. zwischen der Povidon-Jod- und der CHX- bzw. NaCl-Gruppe vor (p<0,001), dies ließ sich im weiteren Verlauf nicht verfolgen. Die angewandte Therapie hat, unabhängig von der Spüllösung, klinisch zum Erfolg geführt. Bei Betrachtung der Wirksamkeit gegen die parodontopathogenen Bakterien A.a., P.g. und T.f. scheint Povidon-Jod überlegen zu sein, jedoch nur bei Betrachtung der Unterschiede innerhalb der Gruppen, nicht bei deren Vergleich.

Thesis (Ph.D.)--Memorial University of Newfoundland, 2002. / Bibliography: leaves 157-161.

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High-speed planing craft slamming into waves can cause structural damage to the vessel as well as hinder or injure personnel onboard. As a result, it is one of the primary constraints that limit the operating envelope of high-speed surface vessels. The controlled motion experiments presented in this thesis were designed to be an intermediate step between vertical water entry tests of a wedge and a traditional tow tank experiment of a planning hullform in waves. This allowed a deeper study of the hydrodynamic loads that occur during slamming. A planing hull model was subjected to controlled motions in the vertical plane to replicate the types of slamming motions that a vessel may experience in the ocean. The slamming events investigated were chosen based on towing tank experiments previously conducted at the U.S. Naval Academy. Hydrodynamic forces were measured globally and also at particular locations near the bow. The vertical motions were programmed into a pair of linear actuators that were rigidly mounted to the towing carriage. The towing carriage prescribed the horizontal motion. Each actuator was independently controlled and capable of moving at 1.3 m/s and 15 m/s^2. Pressure sensors were used to measure the pressure time history at discrete points on the model. Force sensors mounted beneath the actuators were used to compute the overall slamming load and moments induced by the slam event. A combination of other sensors were used to verify the accuracy of the prescribed motion profile. The results suggested that total impact velocity is correlated with the load growth rate. In addition, the velocity normal to the keel was found to be most impactful on the magnitude of the peak force. / Master of Science / The goal of this thesis was to understand the effect of high-speed boats impacting waves. These wave slamming events can harm the boat and make people sea sick onboard. Consequently, the top speed at which these high-speed boats can operate safely is often limited by these wave impacts. The approach taken for this study involved using a model boat that had similar features to high-speed boats seen in the real world. The model underwent specific movements to replicate the impact that occurs when a real boat encounters waves at sea. This method sought to identify important parameters that determine the severity of the slam event. A Vertical Planar Motion Mechanism simulated the slamming motion, allowing the model boat to move at high speeds relative to its size. A variety of sensors located throughout the model collected data on the slam event. The combination of these sensors helped paint a picture of what is occurring during the entire slam event. This study focused on the dynamics that are measured by the sensors. This included the pressure at important locations, the force on the whole model, and the way that the model moves. The Office of Naval Research provided both financial and intellectual support that makes this research possible. Beyond the ONR, many other academic, commercial, and military groups had given their support for this work.

In this research, hydrodynamic analysis, verification and validation will be performed on Generic Prismatic Planing Hull (GPPH) using OpenFOAM v1806 solver interFoam. The numerical simulation will be compared with the experimental result, which is a new set of high-quality experimental tests performed on a large model of a high deadrise prismatic planing hull with flat of chine, tested from pre-planing to fully planing regimes. Firstly, the mesh convergence study and Verification and Validation (V&V) study are performed on the basis of fixed attitude simulations. Three grids are chosen and used to perform the free attitude simulations at the highest speed. Then, mesh convergence study is conducted for the results of highest speed free body simulations, which helps us to choose two grids for other speeds simulations. By performing free attitude simulations using two grids, resistance, heave, trim angle, wetted chine length, and wetted keel length are calculated and compared at seven different tested speeds. Computational Fluid Dynamics (CFD) results analysis regards pressure distribution on the bottom of the hull and in particular areas of interest (flat of chine, spray area, etc.), friction coefficient and volume fraction of fluid in areas where the free surface undergoes violent deformations (overturning wave at the chine and in the wake, spray jet development area). Different algorithms for dynamic mesh simulation and their effect on the quality of CFD predictions are also investigated. / Master of Science / The paper presents the first series of results obtained in an ongoing validation and verification study of inter-dynamic OpenFOAM solver framework on a new set of high quality experimental tests performed on a large (2.4m long) generic planing hull model (GPPH) with high deadrise (18deg), from the pre-planning (Fn∇=2.6) to fully planing (Fn∇=5.7) regimes. This test case is a good benchmark for the free surface capturing model implemented in OpenFOAM which is based on a rather simple transport equation for an additional scalar field that defines the fraction of water in each cell of the computational mesh. This model, in spite of its simplicity, seems capable of reproducing complex violent free surface flows such as that observed in planing hulls, that includes jet spray forming on the bottom and detaching from the chine of the planing hull and overturning waves off the wet chine region, with some nuances. The dependence of the flow solution on the mesh quality is presented and discussed. Practical indication of the level of uncertainty of CFD models for the prediction of the calm water hydrodynamics of the GPPH is given at the highest simulated speed using both fixed and free attitude simulation solutions. Predictions are then extended to the whole speed range, including resistance components, dynamic trim, heave, wetted chine length, and wetted keel length.The effect due to algorithms is also discussed by modifying the settings in wall functions and solvers for the improvements of future simulation.

With the ever present desire for ships and boats to run faster while carrying a greater load, a need exists to reduce the drag while simultaneously increasing hydrodynamic lift. Therefore, a need for semi-planing/semi-displacement hullforms exists for vessels to carry relatively high loads (between 500 and 3000 tons) with a general length Froude number range between 0.4 and 1.0. A hybrid method for calculating the lift and drag of semi-planing/semi-displacement hull forms is developed. This is done by separating the kinematic boundary condition into odd and even parts. The odd and even parts of the kinematic boundary condition are solved independently along with the free-surface boundary condition and superimposed for a complete "hybrid" solution. The superimposed solution components relate to Michell's (1898) "thin ship" integral for odd flow and Maruo's (1967) "flat ship" integral for even flow. A generalized form of Michell's (1898) integral is provided for high speed slender bodies by implementing a more realistic near field condition (Ogilvie, 1975) and a wake trench (Vorus, 2009). A generalized form of Maruo's (1967) integral has also been developed. Comparisons of the generalized methods have been made with available model test and/or analytical data. With this, the concept of the Semihull (Vorus, 2005) is revisited. Some results are given concerning the validity of the Semihull as compared to a traditional displacement ship. Hull form optimization is also explored and the deadrise angle distribution proves to be a major factor in calm water hydrodynamic performance.

<p>It has become increasingly common for a city or region to use sporting and media events to promote themselves. But what is behind these events? What kind of organisation is necessary to plan and run them? In the summer of 2009 the internationally known Volvo Ocean Race will arrive in Stockholm. The race is eight months long and will be hosted in Stockholm for almost the whole of June. The City of Stockholm is behind the event and Stockholm’s marinas will be responsible for making sure that everything runs smoothly and on schedule. Hosting this big event will have an impact on the citizens of Stockholm in many ways. The purpose of this study is to examine the political decision-making behind the event and the first part of the year of planning and preparations that have lead up to it.</p><p>The study is based on interviews with the people responsible for the planning of the event and one politician that were involved in the decision-making. The method that is used in the study is Grounded Theory, which the authors believe has been valuable in this case. The implication of using this method is that the authors have been able to look more closely into the planning of the event without being too influenced by earlier learned theories. The method also can help us to see patterns in the study that otherwise could be missed. In the end of this study we look at previous research and give suggestions for future studies. The authors hope that this study can give inspiration to other researchers in this growing and interesting field.</p>