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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.
51

Zdravotně technické a plynovodní instalace v předškolním zařízení / Sanitation installations and gas installations in Preschool

Műller, Martin January 2018 (has links)
The thesis deals with the technical and gas installation with the use of precipitation water in pre-school facilities. The theoretical part deals with fat traps. The experimental part is focused on water flows, pre-school facilities. In the design and calculation part are drafted sewerage, water supply, gas pipeline, use of rain water and connection of the building to utility networks. The thesis was elaborated according to current standards, laws and decrees
52

Využití srážkových vod ve sportovním a kulturním centru / Rainwater reuse in the sports and cultural center

Bardonová, Hedvika January 2017 (has links)
The diploma thesis is focused on rainwater reuse in the sports and cultural center and elaboration of project sanitary equipment installation. The theoretical part of the thesis is focused on performance issues rainwater reuse in the buildings. In another part of thesis are drawn calculations with three variants of the design volume storage reservoir for rain water. The drawings are part of the project.
53

Developing community-informed technology for harvesting rainwater for domestic use in a semi-arid area of South Africa

Nyamukondiwa, Pertina 16 May 2020 (has links)
PhDRDV / Institute for Rural Development / Approximately, 780 million of people in the world lack access to safe water for domestic use. Out of these, 37 % are found in sub-Saharan Africa. Because of the negative impact of climate variability and change, scarcity of water is likely to continue worsening. Although semi-arid areas experience water shortages, they receive limited amounts of rainfall. Rainwater might help alleviate temporal water shortages. However, rainwater is rarely harvested for use when most needed. The PhD in Rural Development thesis research was carried out in Mabayeni village, which falls under Ward 35 of Collins Chabane Local Municipality in Limpopo Province of South Africa. It was designed to develop a grassroots community-informed prototype for a technology that could be used to harvest rainwater for domestic use. A series of interrelated studies with the following specific objectives underpinned the research: (1) To determine the extent of water scarcity; (2) To identify strategies households used to cope with inadequate availability of water for domestic use; (3) To document the rainwater harvesting techniques rural households used; (4) To compare the features of rainwater harvesting technology that people of different age groups preferred; (5) To develop community-preferred prototypes of rainwater harvesting technology with the best potential to increase access to water for domestic use; and (6) To evaluate the community-preferred prototypes of rainwater harvesting technology. Partly, the study was conducted as a follow-up to a Master’s research study on climate change carried out in 2014 in Mabayeni village. In the 2014 study, it was revealed that water scarcity was a major result of climate change in the area. In addition, Mabayeni was perceived as the driest compared to other villages in the ward. The Cresswell (2013) explanatory sequential mixed method design guided the study. Multi-stage sampling was followed to select respondents. This entailed categorizing respondents first dividing them by age and gender. Respondents were placed in the following clusters: children (boys and girls), youth (male and female), adult (men and women), and the elderly. This was done in order to ensure that there was triangulation of data sources. Various participatory research techniques were used to collect qualitative data for the same reason. For objective 1, data collection techniques such as photo voice, key informant interviews, focus group discussions, participatory mapping, transect walks, storytelling and seasonal diagramming were used. Data were analysed through card sorting, Atlas.ti version 7.5.7-mediated thematic content analysis, map ranking, matrix scoring and conversation analysis. Data collection techniques employed for objective 2 were similar to those used in objective 1 with the exception of participatory mapping. Thematic content analysis in Atlas.ti, map ranking and matrix ranking were used to analyse data for this objective. Only focus group discussions, key informant interviews and transect walks were used to collect data for objective 3. Data analysis techniques used were similar to those used in the previous objective with the exception of map ranking. For objective 4, data were collected through focus group discussions and analysed using matrix ranking and Atlas.ti-aided thematic content analysis. In objective 5, development of artefacts was guided by prototyping and sketch modelling techniques. Techniques such as verbal protocol analysis, mathematical calculations and presentation and analysis were used to analyse data. A questionnaire with open and closed ended questions was also used to collect data for the last objective. Open-ended questions were analysed using thematic content analysis. In addition, the Kruskal Wallis test in SPSS version 25 determined first, the two prototypes (one for zinc and another for thatch roof) that were regarded as the best; and second, if prototype component ratings significantly differed (p <0.05) across prototypes. As a post hoc test, the Dunn’s test in R Statistical Software version 3.3.0 was used for pairwise comparisons. Data saturation determined the sample size. A total of 17 community engagement sessions were held to collect, analyse and validate findings with the grassroots community members in Mabayeni village. Water scarcity in Mabayeni village was reconfirmed to be seasonal. The dry season in each year was five months long. During this time, residents adopted random, risky and unhygienic coping strategies. Although rainwater was collected from rooftops, there was no formal technology used to gather and store large quantities for later use. This was attributed to lack of resources and knowledge on how to develop such technologies. The most commonly preferred features of rainwater harvesting technology across interest groups related to water quality, construction materials and security. All interest groups preferred a technology that harvested clean/potable water. Moreover, the elderly wanted a technology that would help them access the stored water easily. In total, 14 prototypes were developed. When all the interest groups evaluated the prototypes, the ones that boys and men developed were selected as the best for zinc and thatched roofbased technologies, respectively. Selection of a prototype that children produced as the best underlined that children were an important resource that communities should never marginalise. Nor should their ability to contribute useful ideas be underestimated when seeking solutions to local challenges. Active involvement of grassroots community members in the entire design process helped tailor specifications of the technology to user needs, thereby highlighting the importance of inclusive decision making in development practice. This was also important because it created ownership and increased chances of adopting the technology. Lastly, the current study reaffirmed the view that postgraduate degree research can be harnessed to coproduce solutions to community-identified challenges. / NRF
54

Real-time vizualizace povětrnostních vlivů v terénu / Realtime Weather in a Landscape Visualisation

Vlček, Adam January 2009 (has links)
Thanks to the increasing computation power the complexity and dynamism of virtual reality is continuously improving. This work aims to examine influences of weather in a landscape and the means to simulate and dynamically visualize them in real time on the current personal computer hardware. The main goal is to find quick well looking approximations rather than a complex physically correct simulation. The work covers using modern programmable GPU not only for visualization but also as a powerful simulation instrument. The main topic is water movement in the terrain and its effects on it like erosion, snow melting and moisture impact on vegetation. This requires dynamic terrain texturing and algorithms supporting fast geometry and normals updates.
55

Aproveitamento da água da chuva após tratamento por filtração ascendente e radiação ultravioleta / Rainwater utilization after treatment upflow filtration and ultravioleta radiation

Silva, Felipe Amaral 19 August 2015 (has links)
CAPES / A escassez, deterioração da qualidade dos mananciais e o aumento da demanda por água tem sido problema global. Diante desses problemas o uso de fontes alternativas é citado como solução, com destaque para o aproveitamento de água da chuva. Em alguns locais, a água da chuva escoada de telhados tem sido utilizada para fins potáveis e não potáveis e a água da chuva in natura tem qualidade superior ao de águas superficiais e subterrâneas. Embora a água da chuva tenha qualidade físico-química dentro dos padrões de potabilidade, é necessário melhorar sua qualidade para utilizá-la. Assim neste trabalho é avaliado o tratamento da água da chuva por filtro ascendente (volume de 35,4 L) com meio suporte de 0,50 m de seixo rolado e camada filtrante composta de 0,15m de brita, 0,25 m de areia e 0,55 m de carvão ativado e desinfecção por radiação UV. Para melhorar a qualidade da água antes de chegar ao filtro foi instalado um dispositivo de primeiro descarte com volume de 41,4 L. A avaliação do tratamento foi realizada através da análise dos parâmetros pH, temperatura, cor, oxigênio dissolvido, turbidez, amônia, nitrito, nitrato, fosfato, sulfato, DQO e coliformes. Os valores médios obtidos para os parâmetros físico-químicos da água após o tratamento foram de 6,7 para o pH, 22,3 °C para a temperatura, 12,5 UPC para cor, 6,7 mg/L para OD, 0,5 UNT para turbidez, 0,2 mg/L para amônia, 0,01 mg/L para nitrito, 1,7 mg/L para nitrato, 0,2 mg/L para fosfato, 0,7 mg/L para sulfato e 1,3 mg/L para DQO. O tratamento proposto obteve resultados de eficiência para remoção de cor de 22,4%, turbidez de 28,6%, amônia de 50,0%, nitrito de 23,1%, nitrato de 37,0%, fosfato de 95,1% sulfato de 41,7% e DQO de 66,7% e reduziu o numero de microrganismos para um valor menor que o limite detectável do método de análise. Todos os valores médios obtidos para os parâmetros físico-químicos atendem aos padrões exigidos pela portaria 2914/2011 do Ministério da Saúde para água potável. / The scarcity, quality deterioration of water sources and increasing demand for water has been global problem. Faced with these problems the use of alternative sources is cited as a solution, especially taking advantage of rainwater. In some places, rainwater drained roofs have been used for potable and non-potable purposes and rainwater in nature has superior quality to the surface water and groundwater. Although rainwater has physicochemical quality within the potability standards, it is necessary to improve their quality to use it. Thus this work is evaluated treatment of rainwater by upflow filter (35,4 L volume) with support means of 0,50 m of Boulder and filter layer of 0,15 m of crushed stone, 0,25 m of sand and 0,55 m of activated carbon and UV disinfection. To enhance the water quality before reaching the filter was installed a first-flush device with volume of 41,4 L. The characterization of the water before and after treatment was performed through analysis of parameters pH, temperature, color, dissolved oxygen, turbidity, ammonia, nitrite, nitrate, phosphate, sulphate, COD and coliforms. The mean values obtained for the physicochemical parameters of the water after treatment were 6,7 to pH 22,3 °C for temperature, 12,5 UPC for color, 6,7 mg/L to OD, 0,5 NTU for turbidity, 0,2mg/L for ammonia, 0,01 mg/L for nitrite, 1,7 mg/L for nitrate, 0,2 mg/L for phosphate,0,7 mg/L for sulfate and 1,3 mg/L for COD. The obtained results proposed treatment for color removal efficiency of 22,4%, haze 28,6%, 50,0% ammonia, 23,1% nitrite, nitrate 37,0%, Phosphate 95,1%, sulfate 41,7% and COD of 66,7% and reduced the number of microorganisms to a value less than the detectable limit of the analysis method. All mean values obtained for the physicochemical parameters meet the standards required by the Order 2914/2011 of the Ministry of Health for drinking water.
56

Aproveitamento da água da chuva após tratamento por filtração ascendente e radiação ultravioleta / Rainwater utilization after treatment upflow filtration and ultravioleta radiation

Silva, Felipe Amaral 19 August 2015 (has links)
CAPES / A escassez, deterioração da qualidade dos mananciais e o aumento da demanda por água tem sido problema global. Diante desses problemas o uso de fontes alternativas é citado como solução, com destaque para o aproveitamento de água da chuva. Em alguns locais, a água da chuva escoada de telhados tem sido utilizada para fins potáveis e não potáveis e a água da chuva in natura tem qualidade superior ao de águas superficiais e subterrâneas. Embora a água da chuva tenha qualidade físico-química dentro dos padrões de potabilidade, é necessário melhorar sua qualidade para utilizá-la. Assim neste trabalho é avaliado o tratamento da água da chuva por filtro ascendente (volume de 35,4 L) com meio suporte de 0,50 m de seixo rolado e camada filtrante composta de 0,15m de brita, 0,25 m de areia e 0,55 m de carvão ativado e desinfecção por radiação UV. Para melhorar a qualidade da água antes de chegar ao filtro foi instalado um dispositivo de primeiro descarte com volume de 41,4 L. A avaliação do tratamento foi realizada através da análise dos parâmetros pH, temperatura, cor, oxigênio dissolvido, turbidez, amônia, nitrito, nitrato, fosfato, sulfato, DQO e coliformes. Os valores médios obtidos para os parâmetros físico-químicos da água após o tratamento foram de 6,7 para o pH, 22,3 °C para a temperatura, 12,5 UPC para cor, 6,7 mg/L para OD, 0,5 UNT para turbidez, 0,2 mg/L para amônia, 0,01 mg/L para nitrito, 1,7 mg/L para nitrato, 0,2 mg/L para fosfato, 0,7 mg/L para sulfato e 1,3 mg/L para DQO. O tratamento proposto obteve resultados de eficiência para remoção de cor de 22,4%, turbidez de 28,6%, amônia de 50,0%, nitrito de 23,1%, nitrato de 37,0%, fosfato de 95,1% sulfato de 41,7% e DQO de 66,7% e reduziu o numero de microrganismos para um valor menor que o limite detectável do método de análise. Todos os valores médios obtidos para os parâmetros físico-químicos atendem aos padrões exigidos pela portaria 2914/2011 do Ministério da Saúde para água potável. / The scarcity, quality deterioration of water sources and increasing demand for water has been global problem. Faced with these problems the use of alternative sources is cited as a solution, especially taking advantage of rainwater. In some places, rainwater drained roofs have been used for potable and non-potable purposes and rainwater in nature has superior quality to the surface water and groundwater. Although rainwater has physicochemical quality within the potability standards, it is necessary to improve their quality to use it. Thus this work is evaluated treatment of rainwater by upflow filter (35,4 L volume) with support means of 0,50 m of Boulder and filter layer of 0,15 m of crushed stone, 0,25 m of sand and 0,55 m of activated carbon and UV disinfection. To enhance the water quality before reaching the filter was installed a first-flush device with volume of 41,4 L. The characterization of the water before and after treatment was performed through analysis of parameters pH, temperature, color, dissolved oxygen, turbidity, ammonia, nitrite, nitrate, phosphate, sulphate, COD and coliforms. The mean values obtained for the physicochemical parameters of the water after treatment were 6,7 to pH 22,3 °C for temperature, 12,5 UPC for color, 6,7 mg/L to OD, 0,5 NTU for turbidity, 0,2mg/L for ammonia, 0,01 mg/L for nitrite, 1,7 mg/L for nitrate, 0,2 mg/L for phosphate,0,7 mg/L for sulfate and 1,3 mg/L for COD. The obtained results proposed treatment for color removal efficiency of 22,4%, haze 28,6%, 50,0% ammonia, 23,1% nitrite, nitrate 37,0%, Phosphate 95,1%, sulfate 41,7% and COD of 66,7% and reduced the number of microorganisms to a value less than the detectable limit of the analysis method. All mean values obtained for the physicochemical parameters meet the standards required by the Order 2914/2011 of the Ministry of Health for drinking water.
57

Modélisation de l’impact des hétérogénéités lithologiques sur les écoulements préférentiels et le transfert de masse dans la zone vadose d’un dépôt fluvioglaciaire - Application à un bassin d’infiltration d’eaux pluviales / Modelling the impact of lithological heterogeneities on preferential flow and mass transfer in the vadose zone of a galciofluvial deposit – Application to a stormwater infiltration basin

Ben Slimene, Erij 25 April 2016 (has links)
Les bassins d’infiltration font partie intégrante des techniques alternatives de gestion des eaux pluviales en milieu urbain. Néanmoins, la potentialité de transfert de polluants vers la nappe est accrue en cas d’écoulements préférentiels dans les sols sous-jacents. Une bonne compréhension du couplage entre processus d’écoulements préférentiels en zone vadose et mécanismes géochimiques est requise. Cette thèse s’inscrit dans le cadre du suivi d’un bassin d’infiltration depuis plusieurs dizaines d’années de fonctionnement. Le site d’étude est situé sur le dépôt fluvioglaciaire hétérogène couvrant une grande partie de la région lyonnaise. Des auscultations sur une fosse sous le bassin (section 13.5m*2.5m) ont mis en évidence une régionalisation particulière de la pollution dans le sol. Cette étude s’appuie sur une étude numérique visant à identifier l’origine de la régionalisation des polluants et à la relier aux écoulements préférentiels résultant des hétérogénéités lithologiques. En amont de l’étude numérique, les lithofaciès sont complètement caractérisés aux regards de leurs propriétés hydrodynamiques, hydrodispersives et géochimiques. La modélisation numérique permet de souligner l’établissement de cheminements préférentiels en lien avec le contraste de propriétés hydrodynamiques, notamment lorsque de faibles débits sont appliqués en surface. Le rôle de chaque lithofaciès et de l’architecture du dépôt (stratification et inclusions) est clairement identifié. Les répercussions de tels écoulements sur les transferts non réactifs sont ensuite investiguées en combinant l’influence des écoulements préférentiels et le fractionnement de l’eau en fractions mobile et immobile résultant de l’hétérogénéité intrinsèque au sein de chaque lithofaciès. Enfin, ces processus physiques sont couplés à la réactivité géochimique pour le cas d’un polluant modèle (le cuivre) en prenant en compte la réactivité différentielle des lithofaciès. Ces résultats permettent de générer un modèle conceptuel d’écoulements préférentiels et de transfert de masse en milieu fortement hétérogène. / An infiltration basin is a stormwater best management practice (BMP) designed to infiltrate runoff volumes in urban areas. Nevertheless, preferential flow paths in the underlying soil may cause rapid migration of pollutants, thus contributing to groundwater contamination. Understanding the coupling between preferential flow processes in the vadose zone and geochemical mechanisms is then required. This thesis is a part of the follow-up of an infiltration basin for several decades of exploitation. The study site was settled over a highly heterogeneous glaciofluvial deposit covering much of the Lyon region. The investigation of an excavated section of the basin (13.5m long and 2.5m deep) pointed out a specific regionalization of pollution in the soil. This research is based on a numerical study to identify the origin of such a pollutant pattern and link this with preferential flow resulting from lithological heterogeneities. Different lithofacies were fully characterized regarding their hydraulic, hydrodispersive and geochemical properties. The numerical study proves that the high contrast in hydraulic properties triggers the establishment of preferential flow (capillary barriers and funneled flow). Preferential flow develops mainly for low initial water contents and low fluxes imposed at surface. The role of each lithofacies and architecture of deposit (stratification and inclusions) is clearly identified. The impact of such flows on non-reactive transfers is then investigated by combining the influence of preferential flow and pore water fractionation info into mobile and immobile fractions, resulting from the intrinsic heterogeneity within each lithofacies. Finally, these physical processes are coupled to the geochemical reactivity for a pollutant model (copper), taking into account the differential reactivity of lithofacies. These results generate a conceptual model of preferential flow and mass transfer in strongly heterogeneous media.
58

Water quality-based real time control of combined sewer systems / Gestion en temps réel des réseaux d’assainissement unitaires basée sur la qualité de l’eau

Ly, Duy Khiem 28 May 2019 (has links)
La gestion en temps réel (GTR) est considérée comme une solution économiquement efficace pour réduire les déversements par temps de pluie car elle optimise la capacité disponible des réseaux d'assainissement. La GTR permet d'éviter la construction de volumes de rétention supplémentaires, d'augmenter l'adaptabilité du réseau aux changements de politiques de gestion de l'eau et surtout d'atténuer l'impact environnemental des déversoirs d'orage. À la suite de l'intérêt croissant pour la GTR fondée sur la qualité de l'eau (QBR), cette thèse démontre une stratégie simple et efficace pour les charges polluantes déversées par temps de pluie. La performance de la stratégie QBR, basée sur la prédiction des courbes masse-volume (MV), est évaluée par comparaison avec une stratégie typique de GTR à base hydraulique (HBR). Une étude de validation de principe est d'abord réalisée sur un petit bassin versant de 205 ha pour tester le nouveau concept de QBR en utilisant 31 événements pluvieux sur une période de deux ans. Par rapport à HBR, QBR offre une réduction des charges déversées pour plus d'un tiers des événements, avec des réductions de 3 à 43 %. La stratégie QBR est ensuite mise en oeuvre sur le bassin versant de Louis Fargue (7700 ha) à Bordeaux, France et comparée à nouveau à la stratégie HBR. En implémentant QBR sur 19 événements pluvieux sur 15 mois, ses performances sont constantes et apportent des avantages précieux par rapport à HBR, 17 des 19 événements ayant une réduction de charge variant entre 6 et 28.8 %. La thèse évalue en outre l'impact de l'incertitude de prédiction de la courbe MV (due à l'incertitude de prédiction du modèle) sur la performance de la stratégie QBR, en utilisant un événement pluvieux représentatif. La marge d'incertitude qui en résulte est faible. En outre, l'étude de sensibilité montre que le choix de la stratégie QBR ou HBR doit tenir compte des dimensions réelles des bassins et de leur emplacement sur le bassin versant. / Real time control (RTC) is considered as a cost-efficient solution for combined sewer overflow (CSO) reduction as it optimises the available capacity of sewer networks. RTC helps to prevent the need for construction of additional retention volumes, increases the network adaptability to changes in water management policies, and above all alleviates the environmental impact of CSOs. Following increasing interest in water quality-based RTC (QBR), this thesis demonstrates a simple and nothing-to-lose QBR strategy to reduce the amount of CSO loads during storm events. The performance of the QBR strategy, based on Mass-Volume (MV) curves prediction, is evaluated by comparison to a typical hydraulics-based RTC (HBR) strategy. A proof-of-concept study is first performed on a small catchment of 205 ha to test the new QBR concept using 31 storm events during a two-year period. Compared to HBR, QBR delivers CSO load reduction for more than one third of the events, with reduction values from 3 to 43 %. The QBR strategy is then implemented on the Louis Fargue catchment (7700 ha) in Bordeaux, France and similarly compared with the HBR strategy. By implementing QBR on 19 storm events over 15 months, its performance is consistent, bringing valuable benefits over HBR, with 17 out of 19 events having load reduction varying between 6 and 28.8 %. The thesis further evaluates the impact of MV curve prediction uncertainty (due to model prediction uncertainty) on the performance of the QBR strategy, using a representative storm event. The resulting range of uncertainty is limited. Besides, results of the sensitivity study show that the choice of the QBR or HBR strategy should take into account the current tank volumes and their locations within the catchment.
59

Zdravotně technické instalace a plynovod ve výrobním závodu / Sanitary installations and gas pipeline in the factory

Strnadová, Petra January 2019 (has links)
Diploma thesis is aimed to drainage of the sewerage and rain waters, drinkable water and fire-extinguishing water supply and supply of the gas to the gas appliances. Theoretical part is dealing with the sewerage water and its usage. Technical part is dealing with the building water distribution to sanitary installations and gas installations in the chosen solution.
60

Využití srážkových vod v průmyslovém objektu / Rainwater harvesting in an industrial building

Vacek, Jan January 2016 (has links)
Diploma thesis contains a design the plumbing and gas installations in the industrial building. The theoretical part deals with the use of rainwater in the building as the process water and the experimental determination of the flow rate and water needs for the manufacturing and storage hall with built-office. The calculation part deals with the design of variants of plumbing and gas installations in the building manufacturing and storage hall with built-office. The practical part contains a design and project documentation of selected variants plumbing and gas installations in the manufacturing and storage hall with built-office, and the use of rainwater in this type of building.

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