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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.
21

A necessidade da reserva de área para o armazenamento de água no início do crescimento urbano

Juchem, José Ricardo January 2002 (has links)
Atualmente, o desenho urbano tem sido realizado dentro de um âmbito restrito do conhecimento. Este não tem considerado aspectos de drenagem da água que trazem grandes transtornos e custos para a sociedade e o ambiente. O desenvolvimento urbano brasileiro tem produzido um aumento significativo na freqüência de inundações, na produção de sedimentos e na deterioração da qualidade da água. Tal situação é decorrente, na maioria dos casos, da ocupação intensiva do solo urbano. Assim, essa abordagem demonstra, inicialmente, uma visão sobre o desenho urbano e suas interfaces; particularmente as relacionadas com a geografia, o ambiente natural e o construído. Na seqüência, pretendendo atingir o enfoque interdisciplinar, aponta vínculos entre o desenho urbano e a hidrologia através de uma análise ambiental de bairros dos municípios de Porto Alegre e Lindolfo Collor, de modo a identificar relações com a utilização de uma variável - a superfície impermeável, procurando descrever o comportamento ambiental de bacias hidrográficas urbanizadas bem como mostrar a necessidade da reserva de área para armazenar água no início do crescimento urbano. Finalizando, apresenta os principais parâmetros ou características de desenho que deverão garantir a sustentabilidade urbana e hidrológica. Apesar de prematuro, pode-se afirmar que existem indícios para que a dissertação venha suprir algumas deficiências existentes no planejamento urbano-ambientalatualmente adotado. / Actually, the urban design has been realized in the restrict scope of knowledge. It hasn't considered drainage aspects that provide large disturbances and difficulties to society and the environment. The Brazilian urban development has produced significant increase in the flooding frequency, in the sediments produce and water quality. This situation result from, in the majority of cases, the intensive occupation of urban ground. Therefore this subject show the vision about urban design and the interfaces: specially the relation between geography, natural environmental and builded environmental. In the next time, intending to affect the interdisciplinary subject, show bonds between urban design and hydrology through design study in Porto Alegre City and Lindolfo CollorCity to identifythe relationwith a variable- impervious surface, looking for describe the environmental behavior from watershed and show the necessity of water reserve in the beginning urban development. Finally, shows a proposal of sustainability urban design that integrate urban planning and hydrology. Represent a new aspect to come providing some definitions actually adopted in the urban environmental planning.
22

A necessidade da reserva de área para o armazenamento de água no início do crescimento urbano

Juchem, José Ricardo January 2002 (has links)
Atualmente, o desenho urbano tem sido realizado dentro de um âmbito restrito do conhecimento. Este não tem considerado aspectos de drenagem da água que trazem grandes transtornos e custos para a sociedade e o ambiente. O desenvolvimento urbano brasileiro tem produzido um aumento significativo na freqüência de inundações, na produção de sedimentos e na deterioração da qualidade da água. Tal situação é decorrente, na maioria dos casos, da ocupação intensiva do solo urbano. Assim, essa abordagem demonstra, inicialmente, uma visão sobre o desenho urbano e suas interfaces; particularmente as relacionadas com a geografia, o ambiente natural e o construído. Na seqüência, pretendendo atingir o enfoque interdisciplinar, aponta vínculos entre o desenho urbano e a hidrologia através de uma análise ambiental de bairros dos municípios de Porto Alegre e Lindolfo Collor, de modo a identificar relações com a utilização de uma variável - a superfície impermeável, procurando descrever o comportamento ambiental de bacias hidrográficas urbanizadas bem como mostrar a necessidade da reserva de área para armazenar água no início do crescimento urbano. Finalizando, apresenta os principais parâmetros ou características de desenho que deverão garantir a sustentabilidade urbana e hidrológica. Apesar de prematuro, pode-se afirmar que existem indícios para que a dissertação venha suprir algumas deficiências existentes no planejamento urbano-ambientalatualmente adotado. / Actually, the urban design has been realized in the restrict scope of knowledge. It hasn't considered drainage aspects that provide large disturbances and difficulties to society and the environment. The Brazilian urban development has produced significant increase in the flooding frequency, in the sediments produce and water quality. This situation result from, in the majority of cases, the intensive occupation of urban ground. Therefore this subject show the vision about urban design and the interfaces: specially the relation between geography, natural environmental and builded environmental. In the next time, intending to affect the interdisciplinary subject, show bonds between urban design and hydrology through design study in Porto Alegre City and Lindolfo CollorCity to identifythe relationwith a variable- impervious surface, looking for describe the environmental behavior from watershed and show the necessity of water reserve in the beginning urban development. Finally, shows a proposal of sustainability urban design that integrate urban planning and hydrology. Represent a new aspect to come providing some definitions actually adopted in the urban environmental planning.
23

The Role of Structural Stormwater Best Management Practices, Impervious Surfaces and Natural Factors on Base Flow in Massachusetts

Klosterman, Kimberly B 01 January 2012 (has links) (PDF)
This research conducted a GIS analysis of twenty-eight sub-watersheds in Massachusetts and considered five factors which the literature suggested influenced base flow. The literature suggested a positive relation between precipitation, forest cover and base flow and a negative relationship between impervious surfaces, soil drainage class, slope and base flow. A multiple regression analysis of the sub-watershed information confirmed the literature for two factors (soil drainage class and slope) and questioned it on three factors (impervious surfaces, precipitation, and forest cover). The resulting predictive equation indicated that imperviousness and precipitation were the most significant factors affecting base flow. The first derivative of the predictive equation indicated that the interaction effects between these factors had a substantial impact on the base flow values. A number of land use impacts were also considered in this research. Natural land use features such as open land, wetland, forest cover, agricultural, and recreation uses were found to promote the infiltration and increase base flow. These uses promote base flow because their surfaces are more pervious than unnatural surfaces such as high density/multi-family residential, industrial and commercial areas which are mostly covered by impervious surfaces reducing base flow. The research also used a case study of two Massachusetts sub-watersheds to consider the effectiveness of structural stormwater Best Management Practices for promoting base flow. Two sub-watersheds were considered: the Neponset where stormwater BMPs had been implemented and Quinsigamond that had not implemented them. The case study results suggested that structural stormwater BMPs were effective in increasing base flow.
24

A Scientific Communicator's Internship at Hollings Marine Laboratory

Ferrigan, Mollie 13 July 2005 (has links)
No description available.
25

Urbanization and Flooding in Accra,Ghana

Afeku, Kizito 08 August 2005 (has links)
No description available.
26

Autonomous Vehicles: changing the surface landscape of communities through increased green infrastructure adoption and implementation to help US cities combat stormwater runoff

Schmidt, Kelsey L. 24 September 2018 (has links)
No description available.
27

Impacts of Impervious Surface Cover on Stream Hydrology and Stream-Reach Morphology, Northern Georgia

Young, Benjamin J. 05 August 2010 (has links)
No description available.
28

Geospatial Analysis to Site Urban Agriculture

Parece, Tammy E. 17 March 2016 (has links)
The rapid expansion of urban systems in both area and population represents the most significant landuse/landcover change occurring in the world today. Urbanization is often accompanied by increasing environmental degradation. This degradation is related to stormwater runoff, air temperatures greater than surrounding rural areas, increased air and water pollution, losses of vegetated lands, and lack of access to sufficient and healthy foods in lower-income areas. Urban agriculture (UA), a practice long established in previous eras but neglected for many decades, can mediate such concerns by providing greenspaces to improve ecosystem services. Successful practice of UA requires recognition of interactions between social and environmental patterns. Neglect of these interactions leads to failure in spatially integrating social and environmental dimensions of the urban landscape, limiting the success of UA. This study investigates siting of UA within Roanoke, Virginia, a compact urban region characterized by social and environmental conditions that can be addressed by effective siting and practice of UA. This research takes a broader perspective than prior studies on UA and urban greenspaces. It proposes innovative applications of geospatial technologies for urban assessment. Studies on UA have typically focused on food insecurity, while studies on greenspaces focus on parks and tree canopy cover, without investigating interactions that promote synergies between these two efforts. Research over the past few years is now recognizing potential contributions for urban agriculture to alleviate environmental issues such as stormwater runoff, soil infertility, and the urban heat island effect. Little of this research has been devoted to the actual siting of urban agriculture to specifically alleviate both socio-economic and environmental issues. This research applies geospatial technologies to evaluate spatial patterns characterizing both environmental and socio-economic disparities within the City of Roanoke, Virginia. This approach has identified specific locations that are open and available for urban agriculture, and has appraised varying levels of socio-economic and environmental parameters. This research identified, at the census block group level, areas with varying levels of degradation. Thus, those locations in which a new urban agriculture greenspace can contribute to both socio-economic and environmental reparation. This research has identified spatial dimensions in which UA will assist in restoring ecosystem services to guide various food production activities. These results can be generalized to other urban locations and contribute to efficient use of urban land and space, improving the three pillars of worldwide sustainability – economic, environment, and social. / Ph. D.
29

EFFECTS OF IMPERVIOUS SURFACES ON OVERWINTERING SURVIVAL OF EVERGREEN BAGWORM AND ABUNDANCE OF SCALE INSECT PESTS IN THE URBAN ENVIRONMENT

Sujan Dawadi (12218648) 18 April 2022 (has links)
<p>Urban areas are warmer than surrounding rural areas. During the cold of winter, warming increases surrounding host temperature and may improve the overwintering survival of marginally hardy insects like evergreen bagworms. Similarly, during the summer, it has the potential to increase the fecundity and abundance of sap feeding insect pests such as scale insects in ways that change the capacity of their natural enemies to regulate their populations. </p> <p>Although in parts of Indiana winters can be cold enough to kill bagworm eggs, they thrive in cities. I conducted field experiments to determine the extent to which impervious surface near an infestation could keep temperatures warm enough to affect bagworm survival during cold of winter. My results suggest that the percentage of live eggs inside overwintering pupae decreased as ambient temperature drops. This response was moderated by the presence of impervious surface around an infested plant. Eggs found in bagworms collected from host trees surrounded by more impervious surface had a higher chance of survival than those collected from trees with low levels of hardscape. However, impervious surface has its limit such that egg mortality was not buffered by impervious surfaces at temperatures at or below -21.67°C. Similarly, I also conducted field experiments with sap feeding insects on honeylocust trees, a commonly planted tree in cities. Hot sites had a mean daily temperature more than 1.5 °C warmer than cool sites and scale insects were more abundant and fecund on trees in the hottest part of Indianapolis compared to cooler areas. No differences were observed in rates of parasitism on the scale insect. However, I found strong density dependence relation between parasitoids and scales abundance at scale density at or below the levels present in cool sites. The top-down regulation was prevalent at or below a critical density of scale hosts. Conversely, bottom-up regulation was prevalent above this host density as pests benefit from bottom-up factors. This suggests that urban habitats helped the scales to escape biological control by resident natural enemies above critical density of scale hosts. </p> <p>My findings can be useful to landscape designers to design landscapes that are less prone to insect pests. My finding adds to a growing body of evidence that suggests that planting urban trees with lesser amount of impervious surface can help reducing the urban warming effect and increase the regulation from natural enemies. </p>
30

Metodik för beräkning av anslutna hårdgjorda ytor till spillvattennätet / Techniques for calculation of impervious surfaces connected to the sewer system

Larsson, Johan January 2010 (has links)
<p>Sveriges avloppsledningsnät förnyas och utvidgas kontinuerligt. Idag finns ett flertal datorprogram för hydraulisk modellering av flöden och uppdämningsnivåer i spill- och dagvattennät. Modellerna kan även användas som planeringsverktyg för att bedöma effekter av planerade åtgärder samt för uppföljning av utförda åtgärder. Vid uppbyggnaden av en modell krävs beräkningsresultat från en hydrologisk avrinningsmodell som indata. Det största arbetet vid modelluppbyggandet ligger just i beskrivningen av hydrologin. För att kunna simulera avrinningsförlopp i samband med nederbörd på ett verklighetsliknande sätt är kännedom om storleken på och fördelningen av anslutna hårdgjorda ytor till ledningsnätet med snabb nederbördsavrinning väsentligt. </p><p> </p><p>Till kalibreringen och valideringen av avloppsmodellen krävs mätdata. Flödesmätningar är dyra att genomföra vilket har skapat ett intresse att hitta metoder som säkert beräknar de anslutna hårdgjorda ytorna redan från de uppgifter som finns på kartor och i databaser. Svenska riktlinjer för beräkning av hårdgjorda ytor tillhandahålls av branschorganisationen Svenskt Vatten som företräder VA-verken och VA-bolagen i Sverige. Beräkningar med dessa riktlinjer ger dock inte alltid den korrekta storleken på de hårdgjorda ytorna. Syftet med examensarbetet har varit att undersöka olika metoder att beräkna anslutna hårdgjorda ytor till spillvattennätet samt att undersöka huruvida det finns ett samband mellan de avrinningsområden där beräkningarna av de hårdgjorda ytorna inte stämmer. Nio befintliga modeller framtagna i modelleringsverktyget MIKE URBAN användes vid undersökningen. Sex av dessa modeller användes till kalibrering och tre modeller användes till validering.</p><p> </p><p>Undersökningen visade inget samband mellan ytavrinning (reduktionsfaktor) och lutning. Fördelningen av mätpunkter mellan olika jordartskategorier var väldigt ojämn vilket gjorde det svårt att studera huruvida det finns ett samband mellan avrinning och jordart. Resultatet från undersökningen visar att avrinningskoefficienter bör delas upp efter typ av ledningsnät i avrinningsområdet. Metoden med olika avrinningskoefficienter för olika typer av ytor visar på bra resultat för tätbebyggda områden. Metoden med sammanvägda avrinningskoefficienter för olika bebyggelsetyper visar relativt bra resultat med tanke på att det är en överslagsberäkningsmetod.</p><p> </p><p>För tätbebyggda områden bedöms metoden med avrinningskoefficienter för olika typer av ytor fungera bra. Vid mindre tätbebyggda områden ökar osäkerheten. Metoden med sammanvägda avrinningskoefficienter för olika bebyggelsetyper bedöms fungera väl för överslagsberäkningar då den är mindre tidskrävande än den andra metoden. Ingen av de undersökta metoderna bedöms kunna ersätta flödesmätningar. </p> / <p>Sweden’s sewage systems are continuously being maintained and expanded. Several computer programs are today available for hydraulic modeling in sewage and storm water systems. The models can also be used as a planning tool to evaluate effects of planned interventions and to follow up performed interventions. Input data from a runoff model is required at the model build-up. Most of the work in model build-up lies at the description of the hydrology. In order to simulate runoff processes in connection with precipitation, understanding of the size and distribution of impervious surfaces with fast response runoff are essential.</p><p> </p><p>Measurements are required for the calibration and validity check of the model. Unfortunately, flow measurements are expensive to perform. This has created an interest to find methods that safely calculate the connected impervious surfaces already from the information that can be found in maps and in databases. The Swedish guidelines for calculation of impervious surfaces are provided by the Swedish Water and Wastewater Association. Calculations with these guidelines do not always give the true size of the impervious surfaces. The aim of this master thesis was to examine various methods to calculate impervious surfaces connected to the sewage system and whether there is a correlation between drainage areas where the calculations do not agree. Nine existing models developed in the computer program MIKE URBAN were used in this study. Six of these models were used in the calibration and three models were used in the validity check of the methods.</p><p> </p><p>The study did not show any correlation between runoff (reduction factor) and slope. The distribution of datum points between different soil types varied so much that it made it difficult to study whether there was correlation between runoff and soil type. The result from the study showed that the runoff coefficients should be divided after type of sewage system in the drainage area. The method with runoff coefficients for different types of surfaces showed fairly good results for highly urbanized areas. The method with weighted runoff coefficients for different types of habitations showed relatively good results considering that it is a method for rough calculations.</p><p> </p><p>The method with runoff coefficients for different types of surfaces is considered well-functioning for highly urbanized areas. In less urbanized areas, this method showed shorter results. The method with weighted runoff coefficients for different types of habitations is considered well for rough calculations when it is less time consuming than the other method. None of the examined methods are considered able to replace flow measurements.</p>

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