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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

CFD Simulations of Flow Characteristics of a Piano Key Weir Spillway

Sjösten, William, Vadling, Victor January 2020 (has links)
Comprehensive rehabilitation projects of dam spillways are made in Sweden, due to stricter dam safety guidelines for their discharge capacity. The Piano Key Weir (PKW) is an innovative design which has proven effective through several renovation projects made in many countries including France. In this study we investigate the flow patterns around a prototype PKW, located in Escouloubre dam in southern France, with numerical simulations through three different flow cases in Ansys Fluent. A computational domain containing the PKW is created in the CAD software Ansys SpaceClaim for the simulations. Three polyhexcore meshes are further generated using Ansys Fluent Meshing. The three flow cases are then simulated with a Reynolds-averaged Navier-Stokes (RANS) model, coupled with realizable k-epsilon and volume of fluid models. Through an assessment of the discretization error between three meshes, a relative error of one percent is obtained for the discharge rate. The numerical results are qualitatively compared with results from previously conducted physical experiments on this PKW. The RANS model does not capture the water surface undulations (due to turbulence) around the PKW. The effects from under modelled surface undulations are alleviated by inserting an air vent to the PKW, which results in a flow behaviour in good agreement with the physical experiments. Through this alteration, water discharge rates are computed with a maximum discrepancy of five percent compared with the corresponding experimental values. A large eddy simulation should be conducted in the future, to bring further light on air exchange and water interaction phenomena present in the PKW flow pattern.
72

Studie MVE v rámci plavebního stupně Přelouč II / Feasibility study of a small hydropower station within the navigation lock Přelouč II

Kratina, Jakub January 2019 (has links)
The content of this diploma thesis is a feasibility study of a small hydropower station within the navigation lock Přelouč II. This work builds on the framework proposal of one variation of layout arragement of the navigation lock. In this variant is considered to build a lock, which also includes a small hydropower station. At the beginning, the location of individual building objects is resolved with respect to the conditions in the locality. This is followed by a more detailed development of the building and technological part of a small hydropower plant. Part of the thesis is accompanying and technical report, drawing documentation, hydrotechnical and hydroenergetic calculations and photographic documentation.
73

Hydraulický modelový výzkum měrných clon určených pro stanovení průtoku vody v kruhových profilech s volnou hladinou / The hydraulic modelling research of specific shutter intended for determination of water flow in circular profiles with free surface

Heřmanová, Lenka January 2012 (has links)
The main outcome of this Thesis is a set of Q / h characteristic that was obtained extensive hydraulic model research measuring plate designed for the determination of water flow in circular profiles. The final Q / h characteristic are functions of angle and vertical cut remoteness of the top slot from the bottom of the measurement aperture. Part of the output is an overview of the expected values of uncertainties of measurement in practical use in a specific aperture in sewers and evaluation of impacts involved in determining the overall uncertainty of the flow. The performed hydraulic modeling research is therefore possible to determine Q / h and characteristics for circular sections of larger diameter and to determine their uncertainties when using specific plate. For the design and shape measuring plate of the profile with larger average output is part of a supplement for quick design of specific screens.
74

The Sheela-na-gig and the creation of her history : a comparative analysis of two theories concerning the mysterious medieval figure

Pettersson, Joanna January 2017 (has links)
After scholars started conducting research on the medieval Sheela-na-gig carvings, a number of theories regarding the purpose and origin of the figure have been suggested. The question has been tackled through many different approaches, but still remains unfinished as there are no written records explaining what the Sheela-na-gig figure actually is. Scholars have divided into different areas, approaching the discussion from different disciplines: art history, medieval social history, and religious history (both Christian and pre-Christian) to name a few. As the figure is usually found on Christian buildings but is distinguished by very sexual imagery, it leaves the door open for many interpretations. This thesis looks at two common theories on what the Sheela-na-gig is; one which is viewing her as a Romanesque warning against lust and sin, and one which argues that the figure is a folk deity used as an amulet for childbirth, symbolising both life and death. By using discourse theory and a comparative method, this thesis compares the descriptions and arguments of the different theories, and studies the intention behind them. The thesis then shows how the theories choose to focus their search for evidence in order to support their own perspective, while also excluding information which does not serve their particular agenda.
75

The different kinds of protagonists in Robert Louis Stevenson's works : a study of four of Stevenson's novels

George, Kim Allen January 1978 (has links)
No description available.
76

Estrutura da população e período reprodutivo de Leporinus piau Fowler, 1941(Characiformes: Anostomidae) no reservatório de pau dos ferros, semiárido brasileiro / Population structure and reproductive dynamic of leporinus piau Fowler (Characiformes: Anostomidae) in the Pau dos Ferros reservoir, Brazilian semiarid

Araújo, Darlan Dantas Alves de 27 February 2015 (has links)
Made available in DSpace on 2016-08-15T20:31:31Z (GMT). No. of bitstreams: 1 DarlanDAA_DISSERT.pdf: 1327863 bytes, checksum: 20f80b67329558ad38d3402c80b1f9c9 (MD5) Previous issue date: 2015-02-27 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / In the brazilian northeast due to seasonality of rivers and modest hydrological network, water security policy was established, based on the accumulation of water during the rainy season, through the reservoirs construction. This process generate human benefits, but also ecological consequences such as loss of aquatic biodiversity, change in the connectivity of water bodies and modification of biological processes such as reproduction and recruitment of species. In Apodi/Mossoró River basin , Leporinus piau Fowler,1941 is quite important for artisanal and subsistence fishing, however it is necessary to better understand their biology, to establish more effective conservation and management measures. In this context, the objective this work was to study the population structure and reproductive dynamics of Leporinus piau (Fowler, 1941), in the reservoir of Pau dos Ferros, Brazilian semiarid. Specimens were collected quarterly from February 2011 to November 2012 using gillnets. The specimens captured were counted and measured the standard length (cm), total weight (g), and dissected to identify sex, and gonadal maturity stage and weight of gonads (g). Were captured 555 individuals. The highest CPUE value was registered in May/2011 (0.0259 ind. m2*h) and lowest was in August/2012 (0.0008 ind. m2*h). The standard length ranged between 5.9 and 20.7cm and total weigh between 4.16 and 271.50g. The length class of 10-15cm was the most frequent of individuals captured for both sexes. The species presented isometric growth (b=3.01) and L50 was estimated to be 12.76cm. Of individuals captured, 276 were juveniles, 180 males and 99 females. The highest GSI value was observed in February/2011 for females (10.69) and males (5.72). There was a significant a positive correlation between GSI and rainfall. We conclude that the population of L. piau is established in the reservoir with some alterations its population attributes and reproductive period was determined between February and May / No nordeste brasileiro devido a sazonalidade dos rios e rede hidrológica modesta, foi estabelecida uma política de segurança hídrica, baseada na acumulação de água nos períodos de chuva, pela construção de reservatórios. Este processo gerou benefícios humanos, mas também consequências ecológicas, como a perda de biodiversidade aquática, alteração na conectividade dos corpos d água e modificação de processos biológicos como a reprodução e o recrutamento de espécies. No reservatório de Pau dos Ferros, bacia do Rio Apodi/Mossoró, a espécie Leporinus piau Fowler,1941, apresenta grande importância na pesca artesanal e de subsistência, no entanto é necessário conhecer melhor a sua biologia, para estabelecer medidas de conservação e manejo pesqueiro mais eficazes.Neste contexto, o objetivo do trabalho foi avaliar a estrutura da população e a dinâmica reprodutiva de L.piau no reservatório de Pau dos Ferros. As capturas foram feitas com redes de espera de diferentes malhas, entre 17h e 05h. Os peixes capturados foram contados, medidos o comprimento padrão (cm) e peso total (g) e dissecados para identificação do sexo e estágio de maturação gonadal. O maior valor de CPUE ocorreu em maio de 2011 (0,0259 ind. m2 * h) e o menor em agosto de 2012 (0,0008 ind. m2 * h). O comprimento padrão variou de 5,9 a 20,7cm e o peso de 4,16 a 271,5g. A classe de tamanho 10 a 15cm foi a mais frequente para os dois sexos. A espécie apresentou crescimento isométrico (b=3,01) e, L50 estimado em 12,76cm. Foram coletados 555 indivíduos, 276 jovens e 279 adultos, destes 180 machos e 99 fêmeas (1,81: 1)M:F. O maior valor de IGS ocorreu em fevereiro de 2011 para fêmeas (10,69) e machos (5,72). Houve correlação significativa e positiva entre IGS e pluviosidade. Concluímos que a população de L. piau está estabelecida no reservatório com alterações em seus atributos populacionais como a proporção sexual ou mesmo o comprimento de primeira maturação e o período reprodutivo ocorreu entre fevereiro e maio
77

Protipovodňová ochrana obce Brantice / Flood protection of the municipality Brantice

Zahradníková, Lenka January 2019 (has links)
The thesis is concerned with the design of a flood protection for the Brantice municipality, a part of which is an adjustment of the Opava river stream bed, specifically kilometer 77,6554 to 78,7020 and, moreover, a design of a reconstruction of the weir at kilometer 78,340. A capacity assessment of the original stream bed in the built-up area and its surroundings is a part of the thesis, as well as a measure to increase the stream capacity and a design of a boulder chute with a water gate, which replaced the original weir. The program HEC-RAS 4.1.0. was used for the stream capacity calculations.
78

Tenkostěnný pravoúhlý přeliv s přítokovou šachtou / Thin-plate rectangular weir with inlet shaft

Šváb, Jiří January 2019 (has links)
The thesis is divided into literary research and practical part (own measurement). The content of the literary research is a description of the flow over thin-plate rectangular weir. The practical part is focused on a description of the model, measuring equipment and measurement. The results are evaluation of lower and upper surface of nappe, determination of discharge coefficient, coefficient of relative length of shaft, limit value of relative length of shaft for uninfluenced shape of nappe.
79

Vliv pdorysn©ho situovn­ na kapacitu pelivu v prizmatick©m korytÄ / Influence of plan situating of weir in the prismatic channel on discharging capacity

Lukek, Petr January 2016 (has links)
This diploma thesis is focused on determination of plan situating influence of weir discharging capacity. The part of this work is a summary of the information about weirs, principally about determination of discharging capacity on normal weirs, plan deflected and plan radius weirs. Executed model research, which deals with determination of plan situating influence on discharging capacity plan deflected and plan radius weirs in comparison to normal weir, is evaluated in another part of this work. The research is also dealing with influence of aeration of the space under down surface of free jet and influence of downstream water level on discharging capacity. This work compares the results of executed research with available knowledge of other authors, who have dealt with determination of discharging capacity on weirs with different plan situating.
80

Reprezentace genderu na fotografiích nové vlny female gaze / Gender representation in photography of new wave of a female gaze

Rosůlková, Magdaléna January 2020 (has links)
The aim of this work is the qualitative analysis of the new wave of female gaze photographers with a comparison of the female gaze pioneers. For this purpose, there were used photographs by Arvida Bystr​öm​, Petra Collins, Harley Weir, and Cindy Sherman, Nan Goldin, Corinne Day, which were published in fashion magazines such as ​Vogue, Harper's Bazaar, i-D, Dazed, and ​Vice​. The theoretical part examined how female identity has been shaped by western culture and dominant ideology, and how patriarchy paradigm has influenced the visual representation of women in art, pop culture, and advertisement. It is shown through key feminist concepts including Simone De Beauvoir, Betty Friedan, Judith Butler, John Berger, Laura Mulvey, theory of young girl, gagafeminism, and xenofeminism. The second part of the thesis is dedicated to social semiotics analysis of each photograph and the results of this research, which show changes of topics in the female gaze content and the shift to social media-related topics and the virtual representation of women. The work could enrich further research in the field of feminist aesthetics, fashion journalism, photography, advertisement, and social media.

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