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Marine and hydrokinetic (MHK) energy, including ocean waves, tidal current, ocean current and river current, has been recognized as a promising power source due to its full-day availability and high energy potential. At this stage, ocean current energy, tidal energy and ocean wave energy are currently the most competitive sourves among all the categories of MHK. The state of art MHK energy harvesting technology mainly focus on harvesting either ocean wave energy or current energy, but not both. However, a significant amount of ocean waves and tidal/ ocean current coexist in many sites and traditional devices that harvest from a single form of MHK energy, cannot make full use of the coexisting ocean energy. Furthermore, MHK energy harvesting devices need to advance to be cost-effective and competitive with other energy sources. This is difficult to achieve. Ocean wave excitation is irregular, which means that ocean wave height and wave periods are unpredictable and excitation forces on energy harvesting devices can have large variance in amplitude and frequency. Such problems/ restrictions can be possibly addressed by the concept of a hybrid energy converter. In this sense, a hybrid wave-current ocean energy conveter (HWCEC) that simutaneously harvests energy from current and wave with one single power takeoff (PTO) is designed.The wave energy is extracted through relative heaving motion between a floating buoy and a submerged second body, while the current energy is extracted using a marine current turbine (MCT). Energy from both sources are integrated by a hybrid PTO whose concept is based on a mechanical motion rectifier (MMR). In this study, different working modes are investigated together with switching criteria.Simulations were conducted with hydrodynamic coefficients obtained from computational fluid dynamics analysis and boundary element method. Tank tests were conducted for a HWCEC under co-existing wave and current inputs. For comparison, separate baseline tests of a turbine and a two-body point absorber, each acting in isolation, are conducted. Experimental results validate the dynamic modeling and show that a HWCEC can increase the output power with a range between 29-87 percent over either current turbine and wave energy converter acting individually, and it can reduce by up to 70 percent the peak-to-average power ratio compared with the wave energy converter on the tested conditions.Such results demonstrate the potential of the HWCEC as an efficient and cost-effective design. / Master of Science / Ocean energy has been recognized as a promising power source due to its full-day availability and high energy potential. At this stage, ocean current energy, tidal energy and ocean wave energy are currently the most competitive sources among all the categories of ocean energy. The state of art ocean energy harvesting technology mainly focus on harvesting either ocean wave energy or current energy, but not both. However, a significant amount of ocean waves and tidal/ ocean current coexist in many sites and traditional devices that harvest from a single form of ocean energy, cannot make full use of the coexisting energy resource. Furthermore, MHK energy harvesting devices need to advance to be cost-effective and competitive with other energy sources. This is difficult to achieve. Ocean wave height and wave periods are unpredictable and excitation forces on energy harvesting devices can have large variance in amplitude and frequency. Such restrictions can be possibly addressed by the concept of a hybrid energy converter. In this sense, a hybrid wave-current ocean energy converter (HWCEC) that simultaneously harvests energy from current and wave with one single power takeoff (PTO), which consists of ball screw, gearbox, and generator, is designed.The wave energy is extracted through relative heaving motion between a floating buoy and a submerged second body, while the current energy is extracted using a marine current turbine (MCT). Energy from both sources are integrated by a hybrid PTO whose concept is based on a mechanical motion rectifier (MMR). In this study, different working modes are investigated together with switching criteria.Simulations were conducted with hydrodynamic coefficients obtained from computational fluid dynamics analysis and boundary element method. Tank tests were conducted for a HWCEC under co-existing wave and current inputs. For comparison, separate baseline tests of a turbine and a two-body, wave-energy-harvesting structure, each acting in isolation, are conducted. Experimental results validate the dynamic modeling and show that a HWCEC can increase the output power with a range between 29-87 percent over either current turbine and wave energy converter acting individually, and it can reduce by up to 70 percent the peak-to-average power ratio compared with the wave energy converter on the tested conditions.Such results demonstrate the potential of the HWCEC as an efficient and cost-effective design.

This diploma thesis is divided into two parts, theoretical and a part where the results are revealed. In the theoretical part the thesis is mainly focused on the characteristics of the chosen field. It then goes into further detail on the separate themes of each of the problems it is concerned with which is used in its research section. These themes are infrastructure and critical infrastructure, the description of the function of water management while also explaining the terms drinking water and water tank. The thesis also discusses solutions for a possible contamination by chemical, biological and radioactive matter. Terrorism is also discussed in the theoretical part of the thesis. The chosen methods for the evaluation of the results are quantitative and qualitative analysis on the basis of the corresponding technical documentation and business databases. The review of the safety measures used on waterworks objects and of the protection of the sources of drinking water was done through field research, during which, photo documentation was obtained and which was further analysed with varied criterion. There were important findings obtained through this research and it also pointed out the different levels of protection on water tanks in water systems in the Plzeň-North area. Detailed results are at the end of this thesis. With this thesis the author wants to point out the importance of protection of waterworks, mainly the protection of drinking water when it is distributed to its users. The failure to protect this commodity in its full extent would then have far-reaching impact, different from each other only in their extent. The most feared types of said emergency situations would be contamination or the interruption of drinking water supply. The main fields affected by these situations would be the food industry, healthcare, different branches of the industry, agriculture and many other, which are the ones ensuring optimal living conditions and safety for citizens not only in the Czech republic.

Submitted by Mario BC (mario@bc.ufrpe.br) on 2016-08-10T11:56:57Z No. of bitstreams: 1 Thiago Pereira Guerra.pdf: 965910 bytes, checksum: ddd72610f6357a658da184af645fef23 (MD5) / Made available in DSpace on 2016-08-10T11:56:57Z (GMT). No. of bitstreams: 1 Thiago Pereira Guerra.pdf: 965910 bytes, checksum: ddd72610f6357a658da184af645fef23 (MD5) Previous issue date: 2015-02-27 / According to the Serial Discontinuity Concept of the impoundments cause discontinuities in the physical and biological characteristics of rivers, where the combined effect of dams in series may cause negative impacts on fish biology. Thus, the aim of this work was to understand how the reproductive biology of A. britskii is affected by the synergistic effect of the cascade reservoirs in the São Francisco River, with the hypothesis that reservoir cascade alters the reproductive characteristics of A. britskii, reducing their reproductive activity throughout the gradient. The 4651 specimens of A. britskii were caught with gill nets of various mesh openings. Subjects were identified and analyzed their gonads. There was a sex ratio of 2.33 females per male on the whole cascade, with significant difference between the sexes in all the tanks, with the number of females greater than the number of males. The average size at first maturity of females showed that the majority of individuals in all the reservoirs of the cascade, is above the size at first sexual maturity (L50). In the analysis of the RGS, there was a greater reproductive activity in reservoirs Itaparica and Sobradinho, however the average values of RGS were coming in all the reservoirs. The weight / length ratio is found that there is a positive allometric growth for both sexes (b> 3). The IAR was classified as severe in all reservoirs (> 20). In the correlation analysis between the biological aspects and environmental parameters in the reservoirs of the cascade, we found values of rS <0.6, then confirming a low ratio between them. In general, the reproduction of the species A. britskii, is not being influenced by the cascade reservoirs in the São Francisco River, suggesting that the species is well adapted to the environment. / Segundo o Conceito da Descontinuidade Serial, os represamentos causam descontinuidade nas características físicas e biológicas dos rios, no qual o efeito combinado de barragens em série pode causar impactos negativos na biologia dos peixes. Desse modo, o objetivo deste trabalho foi compreender como a biologia reprodutiva do Acestrorhynchus britskii é afetada pelo efeito sinérgico de reservatórios em cascata do rio São Francisco, com a hipótese de que os reservatórios em cascata alteram suas características reprodutivas. Os 4651 exemplares de A. britskii foram capturados com redes de espera, de variadas aberturas de malha e analisadas as características sexuais de cada indivíduo. Observou-se uma proporção sexual de 2,33 fêmeas para cada macho em todo o conjunto da cascata, sendo verificada diferença significativa entre os sexos em todos os reservatórios, com o número de fêmeas maior que o número de machos. O tamanho médio de primeira maturação das fêmeas mostrou que a maioria dos indivíduos em todos os reservatórios da cascata, está acima do tamanho de primeira maturidade sexual (L50). Na análise da Relação Gonadossomática (RGS), constatou-se uma maior atividade reprodutiva nos reservatórios de Itaparica e Sobradinho, entretanto os valores médios de RGS foram próximos em todos os reservatórios. O Índice de Atividade Reprodutiva (IAR) foi classificado como muito intenso em todos os reservatórios (>20). Nas análises de correlação entre os aspectos biológicos e os parâmetros ambientais nos reservatórios da cascata, encontrou-se valores de rS<0,6, confirmando então uma baixa relação entre eles. De forma geral, a reprodução da espécie A. britskii, não está sendo influenciada pela cascata de reservatórios do rio São Francisco, sugerindo que a espécie se encontra bem adaptada ao ambiente.

The thesis deals with design and assessment of all supporting parts of cast-in-place reinforced concrete tank. The thesis includes a technical report, static analysis, drawing documentations, construction proces and visualization. The drawing documentation consists of shape and reinforcement drawings of supporting parts.

The bubble flow is used for different application in steel production and refining processes. It plays in indispensable role in the ladle refining process such as for homogenization and inclusion removal. Hence, it is important to understand the effect of the nozzle outlet geometry on the bubble formation. Three different nozzles with different outlet geometries were examined using a physical model. These geometries were: a) Circle, b) Square with round edges and c) Elliptical. All three nozzles had the same nozzle design and similar outlet cross-section areas. Therefore, the only tested parameter was the outlet geometry. The physical model is a water/air model, that consist of water tank ,the nozzles, gas gauge and a high speed camera. Each nozzle was tested under five different gas flow rates: starting from 10 L/min of air gas flow rate, until a 30 L/min of gas flow rate by incriminating with 5 L/min per experimental trial. Therefore, each nozzle was studied using a 5 experimental sets, so in total 15 experiments were made. For each set, 3000 photos were captured by the high speed camera. The photos were then analyzed using mainly the ImageJ software and the naked eye. After analyzing the photos for the experimental sets the following were found: a) The frequency of bubble formation was for the most part constant with an average of 11 bubbles per second. b) The elliptical nozzle produced for the most part the largest bubbles, while the circular produced the smallest ones. The square nozzle had similar bubble sizes comparable to the elliptical nozzle. c) The circular nozzle resulted in the bubbles with most stable surface, while the elliptical nozzle had the most unstable bubble boundary. The study had a drawback, which is the presence of a jetting flow which reduced the accuracy of the results. Thus, it is recommend that future work can solve this issue by finding at which gas flow rate pure bubbling flow stops for each nozzle geometry. / Bubbelinjektion används för olika tillämpningar inom stålproduktion och raffineringsprocesser. Det spelar en oumbärlig roll i raffineringsprocesser som homogenisering och borttagning av inneslutningar. Därför är det viktigt att förstå effekten av utloppsgeometrin hos munstycket på bubbelbildningen. Tre olika munstycken med olika utloppsgeometrier undersöktes med hjälp av en fysisk modell. Dessa geometrier är: a) Cirkel, b) Fyrkantig med rundade kanter och c) Elliptisk. Alla tre munstyckena har samma munstycksdesign och liknande utloppstvärsnittsarea. Därför är den enda parametern som testas utloppsgeometrin. Den fysiska modellen bestod av en vattentank, munstyckena där var och en undersöks separat, en gasmätare, en höghastighetskamera och modellen använde vatten/luft. Varje munstycke testades under fem olika gasflöden: startande från 10 L/min luftgasflöde, tills 30 L/min gasflöde stegvis 5 L/min per experimentuppsättning. Därför har varje munstycke 5 experimentuppsättningar, så totalt 15 experiment togs. För varje uppsättning togs 3000 bilder med höghastighetskameran. Bilderna analyserades sedan med främst ImageJ-programvara och blotta ögat. Efter att ha analyserat bilderna från experimenten så visade resultaten följande: a) Frekvensen av bubbelbildning var mestadels konstant med ett genomsnitt på 11 bubblor per sekund. b) Det elliptiska munstycket producerade mestadels de största bubblorna, medan det cirkulära producerade de minsta bubblorna. Det fyrkantiga munstycket resulterade i en liknande bubbelstorlek som det elliptiska munstycket. c) Det cirkulära munstycket resulterade i bubblorna med den mest stabila ytan, medan det elliptiska munstycket hade den mest instabila bubbelgränsen. Studien hade en nackdel, vilket är närvaron av ett jetflöde som minskade noggrannheten i resultatet. Det rekommenderas att framtida arbete kan lösa detta problem genom att hitta vid vilken gasflödeshastighet rent bubblande flöde stoppar för varje munstycke

Submitted by Mario BC (mario@bc.ufrpe.br) on 2016-07-27T11:51:10Z No. of bitstreams: 1 Ikaro Daniel de Carvalho Barreto.pdf: 1870932 bytes, checksum: 32a90177a5ca31de1ab6bceeb8cf95a6 (MD5) / Made available in DSpace on 2016-07-27T11:51:10Z (GMT). No. of bitstreams: 1 Ikaro Daniel de Carvalho Barreto.pdf: 1870932 bytes, checksum: 32a90177a5ca31de1ab6bceeb8cf95a6 (MD5) Previous issue date: 2016-03-03 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Knowledge about watershed stream flow regime allows for better public water resource management. However, human activity through reservoir operation can change the stream flow regime. In the Brazilian Northeast region, the São Francisco river basin has a major social and energetic importance. This basin has two large reservoirs, Três Marias and Sobradinho that can affect downstream flow. We select three stations in São Fracisco/MG, Juazeiro/BA and Pão de Açúcar/AL to evaluate influence from the reservoir in the river’s downstream flow. We use Detrended Fluctuation Analysis (DFA), Multi Scale Entropy (MSE) and Sliding Window Analysis (SWA) to evaluate changes in dynamics and complexity of river stream flow. Our major results can be summarized as follows: (1) hydrologic regime in the Juazeiro/BA and Pão de Açúcar/AL stations (closer to Large Hydropower/Reservoir - LHP/R) changed after LHP/R construction from persistent (in scales from 30 days to 1,5 years) to anti-persistent (in scales from 10 days to 1,5 years), while the series from São Francisco/MG station (most distant to LHP/R) doesn’t present any differences in long range correlations after LHP/R construction; (2) MSE analysis shows that series from Juazeiro/BA and Pão de Açúcar/AL stations have more complex dynamics after LHP/R construction and their anomalies have less complex dynamics after LHP/R construction, differently from the São Francisco/MG station series which didn’t show any hydrologic dynamics differences throughout the same periods; (3) changes in Sliding Window SampEn (SWA-SampEn) after Sobradinho LHP/R construction were detected in the Juazeiro/BA and Pão de Açúcar/AL station series. These results indicate that regulation in stream flow by Sobradinho LHP/R has influenced the complexity and long-range correlations on the lower São Francisco river basin. / O conhecimento sobre o regime de vazão de bacias hidrográficas permite-nos planejar melhor as políticas públicas de administração dos recursos hídricos. Contudo, a intervenção humana, através de reservatórios, pode alterar o regime hidrológico. Na Região Nordeste do Brasil, o rio São Francisco se destaca pela sua importância energética e social. Este rio possui dois grandes reservatórios: Três Marias e Sobradinho que afetam a vazão do rio a jusante. Para avaliar a influência dos mesmos na vazão do rio a jusante, foram selecionadas três estações: São Francisco/MG, Juazeiro/BA e Pão de Açúcar/AL. Para analisar as alterações do regime hidrológico foram utilizadas as técnicas de Detrended Fluctuation Anlysis (DFA), Multi Scale Entropy (MSE) e Sliding Window Analysis (SWA). Os principais resultados foram (1) o regime hidrológico das estações de Juazeiro/BA e Pão de Açúcar/AL (próximas das Grandes Centrais Hidrelétricas/Reservatório - GCH/R) foi alterado depois da construção passando de persistente (nas escalas entre 30 dias e 1,5 anos) para anti-persistente (nas escalas de 10 dias a 1,5 anos); na estação de São Francisco/MG (mais distante da GCH/R) não se detectou alteração nas correlações após a construção; (2) a análise MSE mostrou para as estações de Juazeiro/BA e Pão de Açúcar/AL uma dinâmica mais complexa após a construção do reservatório quando comparado com o período anterior nas séries originais e uma dinâmica menos complexa para anomalias, divergindo da série original e de anomalias da estação de São Francisco/MG que não apresentou diferença de complexidade no regime hidrológico entre os períodos anterior e posterior a construção do reservatório; (3) modificações na entropia em janelas móveis (SWA-SampEn) após a construção de Sobradinho/BA para a estação de Juazeiro/BA e de Pão de Açúcar/AL. Estes resultados indicam que o reservatório de Sobradinho/BA, como agente regulador da vazão, influencia a complexidade e correlações de longo alcance da vazão do baixo São Francisco.

This master thesis deals technology of floating islands and their application in practice. In the first theoretical part describes detail of physical and chemical properties of water, the cycle of substances in water and the distribution of standing water, which are considered the most suitable interest sites for the application and instalation of floating systems. The sekond part describes the measurement metodology, which was carried out in several stages on the research land of the Institute of Landscape Water Management. The measuremenr was focused on monitoring the quality characteristics of water in free artificial tanks (lysimeters). The first tank was with floating island, the sekond with floating rack without plants and the third tank with free surface (to ensure the simulation of the natural state). The measurement was under way in the calendar year 2017 and was divided into free stages (spring, summer, winter). During this period were monitored COD, total phosphorus, nitric and amoniacal nitrogen and dissolved oxygen, turbidity, pH, oxidation-reduction potential, water and air temperature and aggregate rainfall. Part of the master thesis is graphical and tabular evaluation of the results. The results are processed in the Minitab 16 statistical software, graphical representation is supplemented by the interlaced linear and cubic regression curves for easier search for the dependence of selected factors. The stages are compared at the end of the master thesis. At hhe end of summer 2017, the first application of the floating island according to utility model No. 31 169 was carried out within the Czech Republic on selected water reservoir in the Bílý Potok basin (Polička).

The thesis is processed from several partial steps. The first step is to calibrate and validate the hydrological model using real meteorological and hydrological data using the balance hydrological model in Runoff Prophet. Furthermore, using the corresponding statistical downscaling in the LARS WG program. Create climatological data sets considering climate change. Hydrological transformation of climatological data by hydrological model to compile sets of hydrological series for Vlára river basin. Recalculate the hydrological data to the body of the dam for the tributary of the Vlára River, including water transfers from the basins of the Sviborka and Smolinka streams. The last step of the work is to analyze the storage volume and its respective improved water outflow from the tank and to assess the impact of climate change on the storage volume of the tank.

This thesis deals with the flood control. In particular, the design of a set of small water reservoirs with retention effect (polders) and their effect on flood flows. The work is divided into two parts, the first part refers to the bachelor thesis. In this thesis is description of the catchment, rainfall-runoff process and the evaluation of the ratio. That was got the necessary information for the design of polders. This is an abbreviated repetition of the contents of the thesis, which is a continuation of this work. The second part deals with the specific design of two reservoirs, including hydro calculations and drawings. For this work were used ArcGIS - ArcMap, Hydrog and to create drawings AutoCAD 2010.