6,046 research outputs found
Characterising the wake of horizontal axis marine current turbines
No full textAn experimental and theoretical investigation of the flow field around small-scale mesh disk rotor simulators is presented. Wake characteristics of the rotor simulators have been measured in the 21m tilting flume at the Chilworth hydraulics laboratory, University of Southampton. A three-dimensional Eddy-viscosity numerical model based on an established wind turbine wake model has been modified to account for the change in fluid and the presence of a bounding free surface. This model shows good agreement with the measured experimental data and further work will be conducted to refine the model. This work has been conducted as part of a DTI-funded project to develop a numerical modelling tool which can predict the flow onto a marine current turbine within an array. The work presented in this paper feeds into this project and will eventually assist the layout design of arrays which are optimally spaced and arranged to achieve the maximum possible energy yield at a given tidal energy site
On using Directional Information for Parameter Space Decomposition in Ellipse Detection
No full textIn this paper we use the parametric polar representation to extend the application of edge directional information from circle to ellipse extraction. As a result we obtain a mapping which decomposes the parameter space required for ellipse extraction into two independent sub-spaces and one final histogram accumulator. The mapping includes the tangent of the angle of the first and second directional derivatives. These tangents are computed by considering edge direction at two border points. We show that the use of gradient information for parameter space decomposition avoids the intensive point labelling imposed by geometric constraints used by other approaches
Biologically generated habitat provision and diversity of rocky shore organisms at a hierarchy of spatial scales
No full textThe diversity and abundance of intertidal organisms found on moderately exposed shores were compared between biologically generated complex and less complex habitats at four different spatial scales. For macrobiota, comparisons were made between Fucus clumps and open areas (barnacle covered or bare rock) and then between barnacle covered rock and ‘bare’ rock. Microbiota were compared on barnacle plates and on the rock surface and at a finer resolution on the plates themselves and pits in the plates. Macrobiota were quantified at two levels of resolution by direct observation and under low power magnification. Microbiota were examined at two levels of resolution with a scanning electron microscope. For macrobiota the average number of species was significantly greater in complex habitats at both levels of resolution. The average number of individuals associated with the Fucus clumps was significantly lower than that on adjacent areas of barnacle covered and bare rock. However, the average number of individuals associated with the barnacle matrix was significantly greater than that on surrounding rock. The differences were entirely caused by a greater abundance of barnacles and species associated with the barnacle matrix on exposed rock outside the Fucus clumps. For microbiota there were large differences in species composition; cyanobacteria were predominant on the rock surface whilst diatoms dominated the barnacle plates. The diversity of this assemblage was low and no differences in species numbers were apparent between the two habitats. At a finer scale, abundance of individuals was much greater in the pits than on flat areas of the surrounding plates and there was a slightly elevated average number of species per sampling unit. This paper illustrates the importance of using a variety of resolutions to measure biodiversity and the importance of biological habitat provision in maintaining biodiversity
Phrenology report of Francis Cotton by A.S. Hamilton, Tasmania 1856
No full textPhrenology report in 1856 by A.S. Hamilton on Francis Cotton who assumed the name William Thompson and the dress of a 'seafaring man ... so as to prevent if possible, any personal knowledge or bias through an oral report.
A speech portrait of our contemporary in A.S. Kushner's lyrics
No full textThe article is devoted to the speech image of the author in A.S. Kushner's poetry. Combining various socially marked colloquial units with traditional poetic means forms individual style of the author and creates a vivid image of our time
Product mix of České dráhy, a.s.
No full textBakalářská práce se zaměřuje na společnost České dráhy, a.s. a její služby poskytované v rámci širokého portfolia produktů všem cestujícím. V první části práce se autor zaměří na všeobecné informace o nástrojích marketingového mixu. Ve druhé části tyto nástroje aplikuje na produkty a služby společnosti České dráhy, a.s., zejména pak na prvky marketingového mixu, kterými jsou 4P, 5P, 7P, SWOT analýza a nástroje 4C. V poslední části dojde k vyhodnocení navržených produktů na základě dotazníkového šetření. Navrhované produkty, které budou respondentům prezentovány, vznikly na základě briefingu se zástupcem Českých drah, a.s. a se zaměstnanci cateringové společnosti JLV, a.s.The Bachelor thesis focuses on the company České dráhy, a.s. and on its services, which are promoted in wide portfolio of products to all customers. In the first chapter the author focuses to general information about tools of Marketing Mix. In the next chapter are these tools applicated to products and services of České dráhy, a.s., mainly to the points of Marketing Mix, which are following tools 4P, 5P, 7P, SWOT analysis and tools of 4C. The conclusion deals with proposed products, which are based on questionnaire results. Proposed results, which will be presented to respondents, were created thanks to briefing with the representative of České dráhy, a.s. and with employees of catering company JLV, a.s.Dopravní fakulta Jana PerneraProblematiku řešenou ve své bakalářské práci dokázal student odpovídajícím způsobem obhájit. Prokázal schopnost samostatné práce. Na doplňkové otázky reagoval pohotově, se znalostí věci a bez závažných nepřesností je zodpověděl.Dokončená práce s úspěšnou obhajobo
A Lagrangian sub-grid model for the dispersion of clouds of tracers
No full textTurbulence models are expected to satisfy the conflicting requirements of accuracy and computational efficiency. Here we discuss a new model that was recently developed in order to accurately and efficiently describe the dynamic of a clouds of tracers particles in Large Eddy Simulations of homogeneous and isotropic turbulent flows. The models incorporates the multi-scale nature of time and space turbulent velocity correlations that are essential in order to correctly reproduce the relative dispersion of multi-particle clouds. The model can be seen as an off-grid solver for the Eulerian velocity field at the positions of a given number of Lagrangian tracers that self-consistently move with it. Extensions to non homogeneous and isotropic turbulence as well as to the dynamics of particles will be discussed
Rate of breakup of small inertial aggregates in homogeneous turbulence
No full textThe hydrodynamic breakup of small inertial aggregates in homogenous and isotropic turbulence is studied through numerical simulations. Small inertial aggregates are subject to shear stress caused by the local velocity gradient and drag stress caused by the relative velocity of the aggregate and the fluid flow. In our simulations, we follow aggregates moving through the flow and record the total stress acting on them. Breakup is assumed to occur when the total stress overcomes a predefined threshold representing the aggregate strength. By determining how long it takes for an aggregate to reach a stress exceeding its strength for the first time, we are able to derive a breakup rate. It is found that with increasing aggregate inertia, the drag stress rapidly becomes the dominant stress resulting in an increase of the breakup rate with increasing the aggregate inertia
Complex analysis of T-Mobile Czech Rpeublic a.s. corporate identity
No full textPráce Komplexní analýza Corporate Identity firmy T-Mobile srovnává teoreticky zpracova-né poznatky s Corporate Identitou již zavedené společnosti. Autor nejdříve popisuje vý-znam pojmu Corporate Identity a jeho součástí. V této části jsou zpracovány dostupné teo-retické poznatky o dané problematice a naznačena očekávání těchto poznatků aplikovaných v praxi. Ve druhé části práce se autor zabývá komplexní analýzou corporate identity firmy T-Mobile Czech Republic a.s. a využívá k tomu konkrétní podklady.The work Complex Analysis of T-Mobile Czech Republic a.s. Corporate Identity theoreti-cally describes known facts about corporate identity and compares them with on market already established company. In first part is author presenting the explanation of corporate identity itself and its components. In second part of this work is author describing the cor-porate identity of T-Mobile Czech Republic a.s. in deep analysis.Ústav marketingových komunikacíobhájen
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