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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

SuDS water storage capacity calculator : A decision support tool for the implementation ofSustainable Drainage Systems in Östersund.

van der Hulle, Tess January 2022 (has links)
Heavy precipitation events are expected to increase in intensity and frequency, due to global warming. Sewer systems might overload during heavy rainfall, resulting in floods which potentially affect all municipalities in Sweden. Traditionally, stormwater is seen as pipe-related problem, but a transition towards Sustainable Drainage Systems (SuDS) has started. SuDS aim to reduce the quantity of the runoff from the site, slow down the runoff to allow (in)filtration, and provide treatment of the surface water before discharge. In Sweden, municipalities are responsible for the sewer system and realization and implementation of climate change adaptation measures, like SuDS. Tools and models support the highly complex selection, location, and design of SuDS, by systematically providing the most relevant information that represents the actual drainage system in the best way possible. Furthermore, models are used to predict the behaviour of SuDS, which may form Decision Support Systems (DSS). The highest interest in SuDS modelling and DSS lies in water quantity, however existing models are complex and lack flexibility, transferability, and stakeholder inclusion. The aim of this project is to provide a tool for the Municipality of Östersund that aids in the decision-making and design process for the implementation of SuDS, concerning their capacity to store stormwater. The ‘SuDS water storage capacity calculator’ can be used to test what (combinations of) SuDS are able to store the stormwater of a heavy rainfall event.The following SuDS components were included in the calculator: extensive green roofs, underground infiltration systems, infiltration basins, swales, porous pavements, detention basins, ponds, and wetlands. Secondly, the technical criteria forming the basis of the calculator were identified through a literature review. These criteria were used to calculate precipitation and the water storage capacity of each SuDS. The calculator was then built in Microsoft Powerpoint using Visual Basic for Applications (VBA). Two case studies were selected in Östersund and explored using the calculator. The water storage capacity of each SuDS component was calculated using scenarios in which 25%, 50%, 75%, and 100% of the total available area in each case study was used as input. Finally, four combinations of SuDS were tested concerning their water storage capacity. All calculated water storage capacity was compared to the amount of water falling on the case study areas during a heavy precipitation event that only occurs once every 100 years.The developed calculator can be used to calculate water storage capacity of SuDS and precipitation in a simple way. The tool contains user input and default values, which can still be changed. Furthermore, the calculator allows comparison between the amount of precipitation and water storage capacity. The results of the scenarios show that underground infiltration systems and detention basins have the highest potential to store stormwater, followed by infiltration basins, porous pavements, and ponds or wetlands. The calculator has limited design options, due to its simplification of reality. However, its limits are mostly applicable further in the designing process. The4calculator gives a rough estimate of the potential water storage capacity of a variety of SuDS components. The calculator is a useful tool before the design process has started, by providing an indication of the options that are worthwhile to consider in terms of water storage capacity. Furthermore, opportunities for optimization of the tool were recognized. The water storage capacity resulting from the different scenarios was compared to the precipitation falling on each case study area. Realistically, the amount of precipitation that exceeds the capacity of the sewer system might not fall directly where the SuDS are located. Finally, the calculator allows applications of a wider range of combinations of SuDS components. / <p>2022-06.16</p>
22

Storm Water Management with BlueGreen Infrastructure in Urban Planning : A case-study in Krokom, Sweden

Suleiko Allansson, Lena January 2023 (has links)
As changing climate and growing urban populations present new challenges for managing both the quantity and the quality of storm waterin cities, nature-based solutions such as blue-green infrastructure arebecoming widely considered as an alternative to grey infrastructure. The benefits, above providing storm water management at a lower cost, are increased ecosystem services. One of such solutions is SuDS: a collective name for drainage systems thatare designed to manage the quantity of runoff, protect or enhance water quality, increase amenity and foster biodiversity. In Sweden there is a lack of research on applying nature-based solutions in planning urban water management. This case study aims to contribute with knowledge of how working with blue-green infrastructure in a systematic way effects the outcome of urban planning and what ecosystem gains can be expected. ASuDS design was created following the SuDS guidelines for a greenfield residential area in the city of Krokom. The design was then compared with the original proposal by the municipality.The results show that the systematic method that SuDS brings to watermanagement planning leads to a different design of a residence area than what traditional methods produce. At the same time the ability to handle extreme rain event is at least as robust, with the ability of the system to generate other ecosystem services and further strengthen the resilience of the area. Further research is needed for a more detailed analysis of the generated ecosystem services. / <p>2023-06-02</p>
23

Mesure et modélisation de la contamination du sol dans les ouvrages de gestion à la source du ruissellement urbain / Assessment of soil contamination in Sustainable Urban Drainage Systems (SUDS) through experimental and modelling approaches

Tedoldi, Damien 03 July 2017 (has links)
L'essor que connaît aujourd'hui la gestion intégrée des eaux pluviales s'accompagne d'un recours croissant à des techniques favorisant l'infiltration de l'eau “à la source”, disséminées sur des bassins versants urbains. Néanmoins, de telles pratiques suscitent des interrogations sur la capacité du sol à jouer le rôle de “filtre” vis-à-vis des polluants présents dans le ruissellement. Ces travaux de thèse s'intéressent à la contamination du sol par les métaux et les hydrocarbures aromatiques polycycliques (HAP) dans ces dispositifs, avec trois objectifs : (i) évaluer les niveaux et l'étendue spatiale de la contamination, (ii) mieux comprendre les mécanismes qui gouvernent le devenir de ces contaminants dans le sol des ouvrages, et (iii) proposer des recommandations sur la conception et la maintenance de ces installations, afin de leur assurer un fonctionnement épuratoire durable.La première partie du travail consiste en une série d'investigations expérimentales sur dix sites d'étude aux caractéristiques contrastées, en service depuis plus de dix ans. Cette phase donne lieu à des cartographies de la contamination superficielle en éléments traces métalliques, puis à des profils verticaux de métaux et HAP, accompagnés de différentes variables explicatives. La distribution spatiale des métaux en surface, qui est toujours structurée autour de la zone d'arrivée de l'eau, porte la signature du fonctionnement hydraulique réel des dispositifs, et révèle le caractère non-uniforme de l'infiltration lors des événements pluvieux courants, qui représentent la plus grande partie du flux polluant à l'échelle annuelle. Dans la zone la plus contaminée des ouvrages, métaux et HAP présentent un enrichissement significatif sur 10 à 40 centimètres de profondeur. La rétention des contaminants résulte de la combinaison de processus physico-chimiques (adsorption) et mécaniques (sédimentation et filtration) ; leur importance relative peut être quantifiée grâce au déficit de zirconium dans le sédiment urbain par rapport au bruit de fond géochimique local. La variabilité inter-sites des niveaux de contamination s'explique à la fois par les capacités de rétention du sol et par les flux de polluants issus du bassin versant d'apport. Bien que les teneurs de surface excèdent, sur certains sites, les seuils internationaux de remédiation du sol pour des espaces “multifonctionnels”, la zone concernée représente — latéralement et verticalement — une région assez limitée dans les ouvrages.La seconde partie de la thèse consiste en une approche de modélisation, dont la finalité est de décrire l'évolution à long terme de la contamination du sol, et d'évaluer l'incidence de différentes pratiques de conception ou de gestion. Une analyse de sensibilité est d'abord mise en œuvre afin d'identifier les “éléments-clés” dans la description du système, et d'orienter le choix du modèle. Les résultats montrent qu'une mauvaise estimation de la dispersivité ou de l'isotherme d'adsorption du sol est susceptible de biaiser significativement la prévision des profils de contamination. Dans la suite du travail, on propose une méthode visant à décrire l'infiltration non-uniforme et la filtration des polluants particulaires. Le modèle ainsi construit est validé via une comparaison entre mesures et simulations sur l'un des sites d'étude faisant l'objet d'une nouvelle caractérisation approfondie. Enfin, une analyse de scénarios illustre les bénéfices d'un amendement de l'horizon superficiel par un matériau adsorbant, ainsi que d'une répartition homogène des flux d'eau en surface, en matière de durée de vie des installations et de fréquence d'intervention. / Sustainable Urban Drainage Systems (SUDS) are increasingly used for stormwater management. However, the generalization of runoff infiltration in urban watersheds raises some concerns regarding the soil's ability to retain ubiquitous micropollutants. The present work addresses soil contamination by trace metals and polycyclic aromatic hydrocarbons (PAHs) in such infiltration devices, with the aims of: (i) appraising the levels and spatial extent of soil contamination, (ii) better understanding the mechanisms which govern the fate of contaminants in these systems, and (iii) identifying design and maintenance guidelines which may enhance long-term pollutant control through SUDS.The first part of the study consists in a series of experimental investigations in ten contrasting study sites, which have been in operation for more than ten years. The two-stage methodology successively leads to cartographies of metal contamination in the surface soil, and vertical profiles of metal and PAH concentrations, along with different explanatory variables. The spatial distribution of trace metals in the upper horizon displays a systematic structure with respect to the inflow area, and bears the time-integrated signature of the infiltration fluxes and flow pathways at the surface. In the most contaminated zone of the facilities, a significant enrichment of metals and PAHs is detectable until 10 to 40 cm depth. Contaminant retention results from the combination of different physicochemical and mechanical processes (resp. sorption and sedimentation/filtration), the contribution of which can be assessed via the zirconium deficit in urban sediment in comparison to the soil's geochemical background. The inter-site variability of contamination levels is attributable to (i) differences in the soil's retention capacities, and (ii) differences in pollutant loads from the watershed. Although surface contents may exceed intervention thresholds for “multi-functional” spaces in several study sites, the area which would require soil remediation is laterally and vertically limited.These experimental assessments are complemented by a modelling approach, to describe the long-term evolution of soil contamination, and to evaluate the effect of various SUDS designs and maintenance operations. A sensitivity analysis is first carried out so as to identify the “key elements” in the system description: the results show that a wrong estimation of the soil's dispersivity or sorption isotherm is likely to induce significant biases in the predicted contamination profiles. A method is then proposed to describe non-uniform water infiltration fluxes, and the filtration of particle-bound contaminants. The model is validated via a comparison between measured and predicted metal profiles in one of the study sites, where a comprehensive soil characterization is undertaken. Finally, a “scenario analysis” illustrates the benefits of (i) using soil enrichment products with enhanced sorption capacities, and (ii) facilitating water spreading at the surface, in terms of “lifespan” of the devices and maintenance requirements.
24

Verdunstung in bebauten Gebieten / Evapotranspiration in Urban Areas

Harlaß, Ralf 04 October 2008 (has links) (PDF)
Die Verdunstung ist die Klimaanlage der Erde. Sie verbindet den globalen Wasserkreislauf mit dem Energiekreislauf. Die Komponenten des Wasser- und Energiekreislaufs stehen für jeden Standort in einem dynamischen Gleichgewicht. Mit der Ausführung von Bauvorhaben wird in das Gleichgewicht eingegriffen. Entscheidend für die Beurteilung der Folgen für die Umwelt sind die langfristigen Auswirkungen. Diese können durch den Vergleich langjähriger mittlerer Jahresbilanzen vor und nach der Bebauung aufgezeigt werden. Bei der Genehmigung neuer Baugebiete müssen diese Auswirkungen ein Entscheidungskriterium werden, wenn der Eingriff in den Naturhaushalt so gering wie möglich gehalten werden soll. Nur die Betrachtung von einzelnen Starkregenereignissen ist nicht ausreichen. Von der Versiegelung der Oberflächen ist die Verdunstung in der Jahresbilanz stärker als die anderen Komponenten des Wasserkreislaufs betroffen. Trotzdem werden bisher bei der Planung neuer Baugebiete hauptsächlich der Oberflächenabfluss und in zunehmendem Maße die Versickerung untersucht. Die Reduzierung der Verdunstung wird zumeist vernachlässigt. Ursache für diese Reduzierung ist die fehlende Zwischenspeicherung des Wassers. Das wirkt sich direkt auf den Energiekreislauf aus, da die nicht für den Verdunstungsprozess benötigte Energie in den bodennahen Schichten bleibt. Im ersten Teil werden die Einflussfaktoren auf die Verdunstung erläutert und ein Überblick über die Berechnungsmethoden gegeben. Im zweiten Teil werden die Oberflächen unbebauter und bebauter Gebiete systematisiert und in Landnutzungsarten unterteilt. Für diese werden die hydrologischen und energetischen Eigenschaften und deren Auswirkungen auf den Wasser- und Energiehaushalt erläutert und die mittleren Jahresbilanzen berechnet. Die tatsächliche Verdunstung wird auf der Basis der Gras-Referenzverdunstung und der Landnutzungsart ermittelt. Ausgangswerte sind langjährige meteorologische Jahresmittelwerte. Die Verdunstung von Wasserflächen wird mit dem Temperaturgleichgewichtsverfahren berechnet. Mit den vorgestellten Verfahren können Einzugsgebiete von Bebauungsplangröße untersucht werden. Es werden Lösungen zur Beibehaltung eines möglichst hohen Verdunstungsanteils in bebauten Gebieten vorgeschlagen. Ansatzpunkt ist dabei stets die Zwi-schenspeicherung des Regenwassers. Am wirkungsvollsten sind dabei Dachbegrünungen, Wasserflächen und Bäume. Das Verfahren wird an zwei Beispielen angewandt - die Erschließung eines Industriegebietes auf einer vorher land- und forstwirtschaftlich genutzten Fläche in Treuen im Vogtland und der Neubau einer Untergrundstation im Zentrum der schwedischen Großstadt Malmö. / Evapotranspiration could be called the air-conditioner of the earth. It is connecting the water and the energy cycle. The components of the water and energy cycle are related to each other in a dynamic system. Urban development is interfering with this system. Changes of the water and energy balance resulting from construction can be calculated on the basis of long-standing annual average balances and compared with the balance in the catchment area before construction. Before granting building permission, the impacts on the water and energy balance should be evaluated in order to minimize interference with nature. Causing long-term impacts must be considered beforehand in planning. Coping only with design storm events does not suffice. Evaporation is more intensely affected by the paving of streets and squares and by constructing buildings then the other components of the water cycle. However, up to now, in the process of design and planning permission of new development areas, the focus is on runoff and, increasingly, on infiltration of rainwater. The large reduction of evaporation is mostly neglected. The reason for the reduction is the lack of buffer storage for water. Thus directly affects the energy cycle. Energy which is not used for evaporation remains in the near-ground layers. In the first part, the factors influencing evaporation are explained and an overview over the methods of calculation is given. In the second part all surfaces of urban and natural areas are systematized and subdivided into types of land use. The hydrological and energy properties as well as their effects on the water and energy balance are elucidated for this types of land use and their average annual balances are calculated. Solutions are presented for retaining in urban areas an evaporation rate as high as possible. Starting point hereby is always the buffer storage of rainwater. Most effective measures are the installation of rooftop greening, open water surfaces and trees. The calculations are performed on the basis of the FAO reference evaporation and the types of land use. Starting values are long-stand average annual meteorologic values. The evaporation of water surfaces is calculated with the temperature balance model. The method is applied to two examples showing the impacts of land use change on water and energy balance: the development of agricultural and forest land in Saxony into an industrial development site, and the impact of the construction of an underground station in the centre of the City Malmö, Sweden.
25

Development of a transitioning approach to reduce surface water volumes in combined sewer systems

Smith, Kerry W. S. January 2016 (has links)
The overarching goal of this research is to establish a successful forum for a transition from the existing paradigm of managing wastewater infrastructure to a more sustainable paradigm that achieves a more efficient utilisation of wastewater assets. A transitioning approach to support a more efficient utilisation of surface water and wastewater assets and infrastructure is proposed and developed. The determined transitioning approach possesses key stages namely developing the arena, developing the agenda, case study, and monitoring. The case study stage investigates a drainage utility identifying their improvement drivers, the removal of surface water through detailed drainage modelling and the financial examination of the costs incurred under the various scenarios conducted. Understanding the implications of removing/attenuating surface water from the network is improved through obtaining data by detailed drainage modelling. Infoworks software is used to investigate and assess the current and future operational scenarios of a wastewater system operating over one calendar year. Modelling scenarios were conducted removing surface water from selected areas focusing on the volumes requiring pumping and durations of pumping station(s) operation prior to treatment during storm conditions. The financial implication of removing surface water in combined sewer systems is examined in three main components. Firstly the costs of electricity incurred at the single sewage pumping station (SPS) investigated during the various scenarios modelled require to be addressed. Secondly the costs to retrofit sustainable urban drainage system (SUDS) solutions needs to be identified. Thirdly the implications of removing surface water for the drainage utility at the national level and the potential saving for householder’s committing to a surface water disconnection rebate scheme. When addressed at the macro level i.e., with over 2,100 pumping stations, some operating in sequence and contained within one drainage utility annually treating 315,360 megalitres the significance of the same multiple quantifiable and intangible benefits becomes amplified. The research aims, objectives and findings are presented to the identified and convened stakeholders. The transitioning approach developed encourages positive discourse between stakeholders. The level of success of the transitioning approach determined is then tested using a quantitative methodology through the completion of questionnaires. From the questionnaires completed the respondents unanimously agreed that surface water flows should be removed as well as reduced from the combined sewer system. The respondents agreed that the removal of surface water from a typical combined sewer system is justified by applying a transitioning approach focusing on the energy consumption required to pump increased volumes during storm events. This response is significant based upon the economic evidence and is contrary to the respondents previous position that finance was their most influencing factor. When provided with other potentially available benefits the respondents were even more supportive of the justification to remove surface water from the combined sewer system. The combined findings of the work presented in this thesis provide further justification that the transitioning approach applied to the removal of surface water from a typical combined sewer system, as determined in this research has been successful.
26

Verdunstung in bebauten Gebieten

Harlaß, Ralf 18 April 2008 (has links)
Die Verdunstung ist die Klimaanlage der Erde. Sie verbindet den globalen Wasserkreislauf mit dem Energiekreislauf. Die Komponenten des Wasser- und Energiekreislaufs stehen für jeden Standort in einem dynamischen Gleichgewicht. Mit der Ausführung von Bauvorhaben wird in das Gleichgewicht eingegriffen. Entscheidend für die Beurteilung der Folgen für die Umwelt sind die langfristigen Auswirkungen. Diese können durch den Vergleich langjähriger mittlerer Jahresbilanzen vor und nach der Bebauung aufgezeigt werden. Bei der Genehmigung neuer Baugebiete müssen diese Auswirkungen ein Entscheidungskriterium werden, wenn der Eingriff in den Naturhaushalt so gering wie möglich gehalten werden soll. Nur die Betrachtung von einzelnen Starkregenereignissen ist nicht ausreichen. Von der Versiegelung der Oberflächen ist die Verdunstung in der Jahresbilanz stärker als die anderen Komponenten des Wasserkreislaufs betroffen. Trotzdem werden bisher bei der Planung neuer Baugebiete hauptsächlich der Oberflächenabfluss und in zunehmendem Maße die Versickerung untersucht. Die Reduzierung der Verdunstung wird zumeist vernachlässigt. Ursache für diese Reduzierung ist die fehlende Zwischenspeicherung des Wassers. Das wirkt sich direkt auf den Energiekreislauf aus, da die nicht für den Verdunstungsprozess benötigte Energie in den bodennahen Schichten bleibt. Im ersten Teil werden die Einflussfaktoren auf die Verdunstung erläutert und ein Überblick über die Berechnungsmethoden gegeben. Im zweiten Teil werden die Oberflächen unbebauter und bebauter Gebiete systematisiert und in Landnutzungsarten unterteilt. Für diese werden die hydrologischen und energetischen Eigenschaften und deren Auswirkungen auf den Wasser- und Energiehaushalt erläutert und die mittleren Jahresbilanzen berechnet. Die tatsächliche Verdunstung wird auf der Basis der Gras-Referenzverdunstung und der Landnutzungsart ermittelt. Ausgangswerte sind langjährige meteorologische Jahresmittelwerte. Die Verdunstung von Wasserflächen wird mit dem Temperaturgleichgewichtsverfahren berechnet. Mit den vorgestellten Verfahren können Einzugsgebiete von Bebauungsplangröße untersucht werden. Es werden Lösungen zur Beibehaltung eines möglichst hohen Verdunstungsanteils in bebauten Gebieten vorgeschlagen. Ansatzpunkt ist dabei stets die Zwi-schenspeicherung des Regenwassers. Am wirkungsvollsten sind dabei Dachbegrünungen, Wasserflächen und Bäume. Das Verfahren wird an zwei Beispielen angewandt - die Erschließung eines Industriegebietes auf einer vorher land- und forstwirtschaftlich genutzten Fläche in Treuen im Vogtland und der Neubau einer Untergrundstation im Zentrum der schwedischen Großstadt Malmö. / Evapotranspiration could be called the air-conditioner of the earth. It is connecting the water and the energy cycle. The components of the water and energy cycle are related to each other in a dynamic system. Urban development is interfering with this system. Changes of the water and energy balance resulting from construction can be calculated on the basis of long-standing annual average balances and compared with the balance in the catchment area before construction. Before granting building permission, the impacts on the water and energy balance should be evaluated in order to minimize interference with nature. Causing long-term impacts must be considered beforehand in planning. Coping only with design storm events does not suffice. Evaporation is more intensely affected by the paving of streets and squares and by constructing buildings then the other components of the water cycle. However, up to now, in the process of design and planning permission of new development areas, the focus is on runoff and, increasingly, on infiltration of rainwater. The large reduction of evaporation is mostly neglected. The reason for the reduction is the lack of buffer storage for water. Thus directly affects the energy cycle. Energy which is not used for evaporation remains in the near-ground layers. In the first part, the factors influencing evaporation are explained and an overview over the methods of calculation is given. In the second part all surfaces of urban and natural areas are systematized and subdivided into types of land use. The hydrological and energy properties as well as their effects on the water and energy balance are elucidated for this types of land use and their average annual balances are calculated. Solutions are presented for retaining in urban areas an evaporation rate as high as possible. Starting point hereby is always the buffer storage of rainwater. Most effective measures are the installation of rooftop greening, open water surfaces and trees. The calculations are performed on the basis of the FAO reference evaporation and the types of land use. Starting values are long-stand average annual meteorologic values. The evaporation of water surfaces is calculated with the temperature balance model. The method is applied to two examples showing the impacts of land use change on water and energy balance: the development of agricultural and forest land in Saxony into an industrial development site, and the impact of the construction of an underground station in the centre of the City Malmö, Sweden.
27

Planning and implementing sustainable urban drainage systems in the built environment

Hellberg, Madeleine January 2020 (has links)
Our planet stands before many great challenges, where climate change and urbanization are two of the major challenges. One of the challenges due to climate change is the increased amount of precipitation and of extreme rainfall, which creates a higher amount of stormwater within the urban areas and an increased risk of urban flooding. Urbanization and an increasing global population put pressure on the environment as more land is exploited and existing urban areas are further developed and densified. Urban areas are already under high pressure to handle the risks of climate change, therefore is climate change adaptation prominent to create more resilient and sustainable urban areas, where stormwater management is one of the challenges that need to be tackled. The aim of this study is to answers one main research question and three sub research question about enablers, barriers, and key factors regarding planning, designing, and implementing sustainable urban drainage systems in the built environment. The used methods are literature study research and multiple case study research. Five case study areas where studied to gather knowledge about areas that have implemented sustainable urban drainage systems. Lessons learned for each of the case study areas where gathered and connected to the literature and used to answer the research questions. The gathered knowledge from the literature and case studies where used to compile recommendations of how a sustainable urban drainage system could be planned and implemented at a pilot study area, which is Välsviken in Karlstad, Sweden. To be able to achieve a sustainable and resilient urban drainage system, that can handle the challenges of climate change and urbanization, it is important that the stormwater planning process is changing. It is crucial to implement facilities and systems that are sustainable, multifunctional, and flexible. The planning process needs to use planning and costing approaches that include flood mitigation and co-benefits, in the long-term and short-term simultaneously. Implementation of sustainable urban drainage systems also needs to be enabled in new areas or being retrofitted into already exploited areas. This could make it possible to create urban areas that are able to tackle the challenges of climate change and urbanization, and create multifunctional, sustainable, and flood mitigated urban areas. / Vår planet står inför många stora utmaningar, där klimatförändringar och urbanisering är två av dessa. En av utmaningarna med avseende på klimatförändringarna är den ökade mängden av nederbörd och extrema regntillfällen, vilka bidrar till större mängder dagvatten i urbana områden och en ökad risk för översvämningar. Urbaniseringen och det ökande antalet invånare globalt sätter press på miljön eftersom mer landyta exploateras och nuvarande urbana områden fortsätter att bebyggas och förtätas. De urbana områdena har redan stora utmaningar med att hantera riskerna med klimatförändringarna. Klimatanpassning är därför viktigt för att skapa mer resilienta och hållbara urbana områden, där dagvattenhanteringen är en av utmaningarna som behöver hanteras. Målet med denna studie är att besvara en övergripande forskningsfråga och tre underliggande forskningsfrågor om möjliggörare, barriärer och nyckelfaktorer gällande planering, design och implementering av hållbara urbana dagvattensystem i den bebyggda miljön.  Metoderna som användes var litteraturstudie och multipel fallstudie. Arbetet började med litteraturstudien och sedan genomfördes en fallstudie där fem områden som implementerat hållbara urbana dagvattensystem undersöktes. Lärdomar från varje område sammanställdes och kopplades samman med den andra litteraturen för att besvara forskningsfrågorna.  Utifrån litteraturen och fallstudierna sammanställdes rekommendationer för hur ett hållbart urbant dagvattensystem kan planeras och implementeras inom ett utvalt studieområde, vilket är Välsviken i Karlstad, Sverige.   För att åstadkomma ett hållbart och resilient urbant dagvattensystem, som kan hantera utmaningarna gällande klimatförändringar och urbanisering, är det viktigt att planeringsprocessen för dagvatten ändras. Det är viktigt att implementera anläggningar och system som är hållbara, multifunktionella och flexibla. Planeringsprocessen behöver använda planerings- och kostandsmetoder som inkluderar översvämningsanpassning och sidofördelar, både långsiktigt och kortsiktigt samtidigt. Man behöver också möjliggöra implementering av hållbara urbana dagvattensystem i nya områden eller anpassa områden som redan är bebyggda. Detta kan bidra till att skapa urbana områden som kan hantera klimatförändringarnas och urbaniseringens utmaningar, och skapa multifunktionella, hållbara och översvämningssäkrade områden.
28

Temporal Dynamics of the Defense Cascade

Nackley, Brittany B. January 2020 (has links)
Understanding physiological responses to threat can inform therapeutic interventions for phobias, anxieties, and PTSD. The defense cascade is reviewed as a theoretical model that predicts behavioral and physiological responses to threats. Nineteen undergraduates (five male), average age 19.4 experienced a novel virtual reality (VR) threat scenario while their physiology was measured. The Subjective Units of Distress Scale (SUDS) was used as a self-report indicator of distress in the research setting. Averaged SUDS reports suggested that the VR stimulus was experienced as threatening for most participants, but their autonomic response patterns did not fit those predicted by the defense cascade. Participants who had scored high on adaptive response questionnaires tended to show uncoupled ANS activation during baseline, but varied across the stimulus condition. Nearly all participants showed either coactivation or reciprocal activation during the stimulus period except those reporting the most dissociative trauma experiences, who mostly showed uncoupled ANS activation. / M.S. / The more we understand about how people’s bodies and their energies act when they feel threatened, the better we can find help for folks who struggle with anxiety, trauma or other challenging conditions. This research uses a theoretical model called the defense cascade to explore how people respond mentally and physically to threatening situations. Nineteen undergraduates went through a virtual reality (VR) experience that was designed to feel threatening while their body and its energy systems were measured. A scale was introduced called the Subjective Units of Distress Scale (SUDS) and was used to help the researchers understand how distressed people felt while they were in the VR experience. Averaged SUDS reports suggested that the VR stimulus was experienced as threatening for most participants, but their body response patterns did not fit those predicted by the defense cascade. Participants whose questionnaire responses suggested they were not anxiety-prone or traumatized, tended to show bodily activation that uncoupled their two autonomic bodily systems during a baseline period before the threatening stimulus. However, their autonomic responses during the stimulus period varied. Nearly all participants showed either both autonomic systems acting together or only one system acting in a mutually exclusive way to the other system during the stimulus period. This was the case for most participants except those reporting the most trauma involving dissociative experiences. This latter group mostly showed uncoupled autonomic bodily patterns.
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Casablanca, une "ville à l'envers". Urbanités métropolitaines au prisme de la marginalité sociale au Maroc / Casablanca, an "inside out city". Metropolitan urbanities throught the social marginality in Morocco

Anglade, Marie-Pierre 14 December 2015 (has links)
Cette recherche porte sur les mécanismes d’ajustement des différentes urbanités en présence à Casablanca, principale métropole du Maroc, par le biais de l’étude de l’appropriation d’espaces publics par des pratiques déviantes. La question des rapports mutuels entre les citadins déviants et l’ensemble des acteurs de la ville (citadins ordinaires et acteurs institutionnels de l’aménagement), incarnée dans le processus d’aménagement urbain du centre-ville à partir de 2002, permet de mettre en évidence l’importance de la visibilité de la transgression des normes sociales. Ces projets contraignant les citadins déviants à réadapter leurs lieux de vie à l’injonction à une urbanité policée sont analysés au regard des limites des compétences des citadins en situation de vulnérabilité et interrogent l’aménagement dans sa capacité à intégrer toutes les composantes sociales de la ville. Dans une démarche de type ethnographique, explorer l’articulation du lien social à la morphologie urbaine permet de comprendre les transformations des valeurs à l’oeuvre dans des situations de déviance, révélatrices de changements affectant les formes familiales et l’ensemble de la société marocaine, pour les hommes et les femmes en quête d’individuation. / This research is a study of the adjustment of different urbanities present in Casablanca, Morocco’s main metropolis, where public spaces are appropriated by city-dwellers for their deviant practices. The issue of mutual relations among the city-dwellers and all the city stakeholders (ordinary city-dwellers and institutional players involved in planning) embodied in the urban planning process of the city center since 2002 highlights the importance of visibility of the transgression of social norms. The development projects, which force deviant city-dwellers to readjust their living places to a constraining civilized urbanity, are analyzed in terms of the limitations of the competencies of these city-dwellers, who are in a vulnerable situation. The projects also call into question urban planning in its ability to incorporate all the social components of the city. Using an ethnographic approach to explore the relationship of social ties with urban morphology helps to understand the transformations of values at play in situations of deviance, which reveal changes in family structure and the entire Moroccan society for men and women in search of individuation.
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ECONOMIC AND ENVIRONMENTAL IMPACTS OF STORMWATER MANAGEMENT : Case study: Cost-effectiveness evaluation of Proposition O projects

Mahdian, Adrian January 2020 (has links)
Stormwater Management (SWM) or Best management practices (BMPs) treat the stormwater runoff that carries pollutants. Pollutants in the waters and in the stormwater, negatively impact the environment, the ecology, and natural resources. Stormwater Control Measures (SCM) are used in different projects to improve water quality and quantity. This thesis aims to understand the connection between SWMs, the economy, and environmental sustainability. This thesis evaluates the cost-effectiveness of SWMs in Mediterranean climates. The research aims to guide the next project managers to choose better SWMs based on cost-effectiveness, socio-economic, and environmental implications. Various studies suggest that the terms SWM, SWM, and SCM are used interchangeably. The research methodology uses a mix of qualitative and quantitative data analysis The research was conducted in Los Angeles at the request of UCLA. Therefore, it focused on water quality improvement projects in Los Angeles. The costs for the projects, areas, and whatSWMs are used will be acquired through data gathering and personal communication with experts. This thesis compares several projects which include different SWMs. It calculates the cost-effectiveness with two different methods, firstly, the cost per drainage area, and secondly, the cost per pollutant removed. Data is gathered from the city of LA and other secondary data sources to calculate the cost-effectiveness. The calculation results showed that the Glenoaksproject and the Machado lake project were the most cost-effective. Glenoaks utilizes infiltration wells and grass swales, and the Machado lake is a large wetland. Based upon these facts, generally, wetlands and grass swales can be recommended for Mediterranean climates. The expensive total costs of SWMs or their inability to remove pollutants can strongly affect the cost-effectiveness of some projects, and produce a negative impact on the economy. Quantitative assessment of study investigates cost-effectiveness of SWMs and for highlighting its economic impact. For qualitative assessment thematic analysis of 14 sample studies related to stormwater management (SWM) was carried out. Findings reveal that 78% of sample studies reflect the themes associated with the positive economic impact of SWMs. Additionally, the sample studies confirm a 76% positive impact of SWMs on the environment and ecology of the region. Further research with better data and more accurate calculations are needed. It would be beneficial if other factors such as recreation and unquantifiable factors such as the aesthetic improvements and community benefits were incorporated into or considered together with the cost-effectiveness for future projects.

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