• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 13
  • 2
  • 1
  • 1
  • 1
  • Tagged with
  • 20
  • 20
  • 7
  • 6
  • 5
  • 4
  • 3
  • 3
  • 3
  • 3
  • 3
  • 2
  • 2
  • 2
  • 2
  • 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.
11

Re-Connecting: Revitalizing Downtown Clearwater With Environmental Sensibility

Duran, Diego 15 July 2010 (has links)
Many downtowns in North America have been severed from the rest of the city and from the contextual relationship to their surroundings. Sundered from their context, the ecological characteristics of a site are frequently taken for granted, and the disengagement of its public spaces erodes the downtown's character as well as the urban fabric. Downtown Clearwater has lost the vitality and vibrancy that once characterized it as a lively district. Because of recent developments in the downtown area, public spaces have been lost between parking lots, high rises and a small number of sporadic residential pockets. Some of the most important streets fail to create connections for the pedestrians to the surrounding public spaces and areas of interest; as a result some local businesses have dried up, affecting Downtown Clearwater's economy and its community. There is also a disconnection of the downtown with its context and it is evident that some of the major ecological and environmental characteristics of the site have been ignored through its development. This thesis studies how the ecological characteristics of a site can be integrated into the core of its design and experience. The Thesis proposes to revitalize Downtown Clearwater with a new system of green corridors that will promote activity and circulation. The corridors will define a new invigorating framework of points of interest supported by surrounding land uses. The main objectives of the project are to create a new urban destination, enhance the pedestrian experience, reconnect public spaces, cleanup water runoff and organize circulation of bicycles and pedestrians.The thesis emphasizes the design and development of a specific node and section of the green corridor system to explain the design.
12

Evaluation of an Exfiltration Trench for Treatment of Highway Storm Water Runoff

Al-Tarawnah, Ahmad M. 24 September 2013 (has links)
No description available.
13

Risk för spridning av markföroreningar från MIFO-klassade områden i Stockholms län vid ökad avrinning till följd av klimatförändringar / Risk of contaminant spread from contaminated sites in Stockholm County due to increased water runoff caused by climate change

Wikström, Alice, Lundgren, Lovisa January 2018 (has links)
No description available.
14

Sustainable Stormwater Management: Applying Green Infrastructure Principles in Addis Ababa

Mezgebe, Bineyam January 2009 (has links)
No description available.
15

Exfiltration Trenches for Post Construction Storm Water Management for Linear Transportation Projects: Field Study of Suspended Materials

Abu Hajar, Husam A. 18 April 2012 (has links)
No description available.
16

Analýza srážko-odtokových procesů a erozních charakteristik vybraného povodí při různém uspořádání krajiny

VANČUROVÁ, Lenka January 2019 (has links)
The diploma thesis focuses on the analysis of rainfall-runoff processes and erosion characteristics of selected catchment in different landscape management. This analysis was solved at the Lukavecký brook catchment, which is located in the Pelhřimov district in Vysočina region. The theoretical part of the thesis describes the rainfall-runoff process and then focuses more on individual processes. It also characterizes water erosion, its consequences, forms and erosion control. At the end of the theoretical part are described methods of calculation of water runoff and water erosion. The practical part describes the catchment of the Lukavecký brook, its characteristics of natural conditions and the threat of water erosion. Then there is a procedure for processing of bases and data in the program ArcGIS. Subsequently, it includes an assessment of the different measures and changes in the type of land to drain water from the catchment and erosion threat.
17

EFEITO DE RESERVATÓRIO DE APROVEITAMETO DE ÁGUA DA CHUVA SOBRE REDES DE DRENAGEM PLUVIAL / EFFECT OF RAINWATER HARVESTING RESERVOIRS OVER URBAN DRAINAGE NETWORKS

Hentges, Sara Ceron 28 August 2013 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The urban growth and the disordered occupation of cities have increased the frequency and severity of flooding in urban areas, which occur mainly due to the modification on rainwater natural infiltration, as a result of soil imperviousness increase. The use of compensatory techniques (CT) for stormwater control has been encouraged through public polices, attempting to apply for sustainable solutions to mitigate the urbanization´s impact. An alternative already widespread in some Brazilian cities is the use of micro reservoirs (MR), which temporarily store volumes from impervious areas, and gradually emptying the water stored. Along this requirement, implementation of Rainwater Harvesting Reservoirs (RHR) to non-potable purposes is often encouraged in order to reduce the consumption of drinking water for less noble purposes, and to preserve the fountainheads. Some bibliographies suggest that in addition to these benefits, the RHR can be considered a CT also, once it stores the stormwater runoff, and therefore, in some cities where the MR is required, many buildings are already using the RHR to replace it. However, there are not many conclusive studies related to the real benefits and impacts that capturing rainwater and its use have on micro drainage networks, and specifically if such technique can be considered as a compensatory one. Thus, the main objective of this research was to evaluate whether RHR can be considered as an alternative to promote the quantitative stormwater control. For that, a comparative analysis was made between the impact that RHR use generates on micro drainage flows and networks, and the impact generated on a MR containing system. Such analysis was performed through a modeling of a urban watershed from Porto Alegre / RS, with 977 ha, 30.720 standard lots and around 70 km of micro drainage networks. The simulated MRs were designed according to the Decree No. 15.371/06 of the city of Porto Alegre, which aim to control the runoff at the source and it resulted in volumes of 3.13 m³ and 3.75 m³ for rainfall project with return period of 5 and 10 years (CP-CP-TR5 and TR10), respectively, answering to the allowable flow restriction at the lot outlet (VR = 0.624 L / s). The micro drainage networks were designed for both situations, with and without MRs, for CP-TR5 and CP-TR10. For sizing of the RHRs a continuous simulation of 12 years of precipitation data and demands series for non-potable uses data was performed, both with time step equal 5 minutes, resulting in volumes of 5.000, 10.000 and 15.000 liters due to the achieved service guarantee. These volumes of RHRs replaced the MRs and new modeling were performed considering observed rainfall data real from the continuum time series. It was found that the RHRs were not effective to maintain the VR at lots outlet, and the restriction value was exceeded for several times. For the simulated time seriess only the volume of 750 m³ would be appropriate to ensure only one offense within 10 years of simulation. That occurs because must have sufficient volume to store the expected drained volume, without spillage, regardless of the reservoir storage condition. However, if there is a very large storage capacity and demands are comparatively small, the reservoir does not empty. It was found, therefore, that exists an antagonism when trying to use the RHR for two functions: runoff control and water supply for non-potable purposes demand, since the attempt to ensure the fulfillment to the first function prevents the deployment of such large volumes. Overtopping of RHRs to 12 critical simulated events committed the microdrainage networks capacity, generating flooding in the streets along several drainage network ranges. Considering the same 12 critical events and MRs in lots were identified only four overflowing and lower overflows, which ended up committing a lower extent of drainage networks. Therefore, based on analysis of the continuous simulation with RHRs, it was found that it is not possible to consider it an equivalent technique to the MRs for storm water runoff control, unless the reservation volumes are extremely high, which would make its implementation on a few square meters lot impossible. / O crescimento urbano e a ocupação desordenada das cidades têm aumentado a frequência e a severidade das enchentes em áreas urbanas, que ocorrem, principalmente, devido à modificação nas condições naturais de infiltração das águas pluviais, decorrentes do aumento da impermeabilização do solo. Em busca de soluções sustentáveis para mitigar os impactos da urbanização, as políticas públicas vêm incentivando o uso de técnicas compensatórias (TC) para o controle do escoamento superficial. Uma alternativa já difundida em algumas cidades brasileiras é o uso de microrreservatório (MR), que armazena temporariamente os volumes oriundos do escoamento das áreas impermeáveis, esvaziando gradativamente a água armazenada. Paralelamente a essa exigência, a implementação de reservatórios para o aproveitamento da água da chuva (RAAC) com fins não potáveis vem sendo incentivada, com o intuito de reduzir o consumo de água tratada para fins menos nobres e preservar os mananciais. Algumas bibliografias sugerem que além desses benefícios, o RAAC pode ser considerado igualmente uma TC, já que armazenaria o escoamento pluvial, e por essa razão, em algumas cidades onde o MR é exigido, muitas edificações já estão utilizando o RAAC em substituição a este. No entanto, verifica-se uma falta de estudos conclusivos a respeito dos reais benefícios e impactos que a captação da água da chuva e seu aproveitamento têm sobre as redes de microdrenagem pluvial e, especificamente, se esta técnica pode ser considerada como compensatória. Assim, o principal objetivo desta pesquisa foi avaliar se os RAACs podem ser considerados como medidas para o controle quantitativo do escoamento pluvial. Para isso, foi realizada uma análise comparativa do impacto que a sua utilização gera sobre as vazões e redes de microdrenagem, com o impacto gerado em um sistema com MR. A análise foi realizada mediante modelagem matemática de uma bacia hidrográfica urbana da cidade de Porto Alegre/RS, com 977 ha, 30.720 lotes padrão e cerca de 70 km de redes de microdrenagem. Os MRs simulados foram dimensionados de acordo com o Decreto n° 15.371/06 da cidade de Porto Alegre para o controle do escoamento na fonte, resultando em volumes de 3,13 m³ e 3,75 m³, para chuvas de projeto com 5 e 10 anos de período de recorrência (CP-TR5 e CP-TR10), respectivamente, atendendo à vazão de restrição permissível na saída do lote (VR = 0,624 L/s). As redes de microdrenagem foram dimensionadas para as situações que contemplaram os MRs e para a situação sem os MRs, para CP-TR5 e CP-TR10. Para o dimensionamento dos RAACs foi realizada uma simulação contínua de 12 anos de dados de chuvas e série de demandas para fins não potáveis, ambas com intervalo de tempo de 5 minutos, tendo sido determinados os volumes de 5.000, 10.000 e 15.000 litros como os mais adequados para a edificação, em razão da garantia de atendimento atingida. Esses volumes de RAACs substituíram os MRs e novas modelagens foram realizadas considerando tanto eventos de projeto, como as chuvas reais da série contínua. Verificou-se que os RAACs não são eficientes na manutenção da VR na saída dos lotes, sendo que ao longo da série história simulada a mesma foi infringida várias vezes. Para a série histórica simulada apenas um volume de 750 m³ seria adequado para garantir apenas uma infração em 10 anos da simulação. Isso ocorre porque deve haver volume de espera suficiente para armazenar os volumes escoados, sem que haja vertimento, independentemente da condição de armazenamento do reservatório; no entanto, se existe uma capacidade de armazenamento muito grande, e as demandas são comparativamente pequenas, o reservatório não esvazia. Constatou-se, dessa forma, que existe um antagonismo quando se pretende utilizar o RAAC para as duas funções: controle de escoamento superficial e garantia de atendimento à demanda com fins não potáveis, visto que a tentativa de garantir o cumprimento da primeira função inviabiliza a implantação de volumes tão grandes. O extravasamento dos RAACs para 12 eventos críticos simulados comprometeu a capacidade das redes de microdrenagem, gerando armazenamento de água nas ruas ao longo de vários trechos. Considerando os mesmos 12 eventos críticos e os MRs nos lotes foram identificados apenas 4 extravasamentos e menores vazões extravasadas, o que acabou comprometendo uma menor extensão das redes de drenagem. Portanto, com base nas análises da simulação contínua com os RAACs, verificou-se que não é possível considerá-lo uma técnica equivalente aos MRs para o controle do escoamento pluvial, a menos que os volumes de reservação sejam extremamente elevados, o que tornaria impossível a sua implementação em um lote de poucos metros quadrados.
18

Modelling calving and sliding of Svalbard outlet glaciers : Spatio-temporal changes and interactions

Vallot, Dorothée January 2017 (has links)
Future sea level rise associated to global warming is one of the greatest societal and environmental challenges of tomorrow. A large part of the contribution comes from glaciers and ice sheets discharging ice and meltwater into the ocean and the recent worldwide increase is worrying. Future predictions of sea level rise try to encompass the complex processes of ice dynamics through glacier modelling but there are still large uncertainties due to the lack of observations or too coarse parameterisation, particularly for processes occurring at the glacier interfaces with the bed (sliding) and with the ocean (calving). This thesis focuses on modelling these processes from two marine-terminating glaciers in Svalbard, Kronebreen and Tunabreen. By inverting three years of high temporal resolution time-series of surface velocities on Kronebreen, basal properties are retrieved with the ice flow model Elmer/Ice in Paper I. Results suggest that surface melt during the summer greatly influences the dynamics of the following season and that sliding laws for such glaciers should be adapted to local and global processes changing in space and time. The subglacial drainage system, fed by the surface melt, is modelled in Paper II during two melting seasons. Results show different configurations of efficient and inefficient drainage systems between years and the importance of using a sliding law dependent on spatio-temporal changes in effective pressure. The interaction with the ocean is incorporated in Paper III by combining a series of models, including an ice flow model, a plume model and a particle model for discrete calving and compares the output with observations. Results show the importance of glacier geometry, sliding and undercutting on calving rate and location. However, more observations and analytic methods are needed. Time-lapse imagery placed in front of Tunabreen have been deployed and a method of automatic detection for iceberg calving is presented in Paper IV. Results show the influence of the rising plume in calving and the front destabilisation of the local neighbourhood.
19

Characterizing Storm Water Runoff from Natural Gas Well Sites in Denton County, Texas

Wachal, David J. 05 1900 (has links)
In order to better understand runoff characteristics from natural gas well sites in north central Texas, the City of Denton, with assistance through an EPA funded 104b3 Water Quality Cooperative Agreement, monitored storm water runoff from local natural gas well sites. Storm water runoff was found to contain high concentrations of total suspended solids (TSS). Observed TSS concentrations resulted in sediment loading rates that are similar to those observed from typical construction activities. Petroleum hydrocarbons, in contrast, were rarely detected in runoff samples. Heavy metals were detected in concentrations similar to those observed in typical urban runoff. However, the concentrations observed at the gas well sites were higher than those measured at nearby reference sites. Storm water runoff data collected from these sites were used to evaluate the effectiveness of the water erosion prediction project (WEPP) model for predicting runoff and sediment from these sites. Runoff and sediment predictions were adequate; however, rainfall simulation experiments were used to further characterize the portion of the site where drilling and extraction operations are performed, referred to as the "pad site." These experiments were used to develop specific pad site erosion parameters for the WEPP model. Finally, version 2 of the revised universal soil loss equation (RUSLE 2.0) was used to evaluate the efficiency of best management practices (BMPs) for natural gas well sites. BMP efficiency ratings, which ranged from 52 to 93%, were also evaluated in the context of site management goals and implementation cost, demonstrating a practical approach for managing soil loss and understanding the importance of selecting appropriate site-specific BMPs.
20

Návrh a optimalizace vybraných stavebně technologických procesů trvale udržitelné šetrné výstavby vegetačních střech / THE DESIGN AND OPTIMALIZATION OF SELECTED CONSTRUCTIONAL TECHNOLOGICAL PROCESSESS OF SUSTAINABLE ENVIRONMENT-FRIENDLY CONSTRUCTION OF THE VEGETATIVE ROOF

Selník, Petr Unknown Date (has links)
This presented dissertation is focused on the installation technology of green roofs and sustainable long-term stability considering the construction and runoff water management. The main topic of the study and research was the technical layer application, especially the newly developed retention board made of recycled polyester fiber and non woven textiles. Consistent monitoring was performed in the climatic conditions of the Czech Republic and selected installation technology.

Page generated in 0.0755 seconds