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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.
31

Stormwater Infiltration and Groundwater Integrity: An Analysis of BMP Siting Tools and Groundwater Vulnerability

Gallagher, Kristopher Craig 22 March 2017 (has links)
Nonpoint source pollution captured by urban stormwater runoff is the greatest challenge for surface water quality improvements. Computer-based design tools have been developed to help mediate this issue by guiding end users through the implementation of decentralized stormwater management. The majority of these tools focus on treatment via biofiltration, yet concern regarding this treatment regime is rising. Case studies from research past clearly indicate the susceptibility of groundwater to contamination from extensive anthropogenic activity at the surface. Contaminants, such as nitrates and pathogens, are not completely removed before runoff enters the underground watercourse. Additionally, national and state legislation, which explicitly lists where neglect for groundwater quality is permissible—exacerbate concerns. This research analyzes the efficiency the BMP Siting Tool developed by the US Environmental Protection Agency and the Grey-to-Green Decision Support Tool developed by the University of South Florida. The tools were used to obtain cartographic data illustrating suitable sites for bioswales and infiltration basins throughout northern portion of Hillsborough County, Florida. This data was then integrated with the Karst Aquifer Vulnerability Index (KAVI) groundwater vulnerability model. The area of bioswales and infiltration basins that intersected areas of the KAVI model listed as ‘highly vulnerable’ or ‘moderate-to-highly vulnerable’ was calculated. This permitted an assessment of which BMP facility had the greatest sitings atop vulnerable areas, respective of the tool. The BMP Siting Tool sited 2.80% of all bioswales and 27.89% of all infiltration basins above vulnerable areas. Likewise, the Grey-to-Green Decision Support Tool sited 21.66% of all bioswales and 9.62% of all infiltration basins above vulnerable areas. These results prompted the development of a supplemental groundwater vulnerability framework to be incorporated into both tools’ analytical process.
32

Multi-Criterion Macro-Siting Analysis of Offshore Wind Farm Potential in Sweden. / Multikriterie- och makroplaceringsanalys av havsbaserad vindkraftspotential i Sverige.

Sundström, Oskar January 2021 (has links)
Sweden has a great potential for offshore wind energy production. As technology develops and policies change, construction of offshore wind farms in the country is likely to increase. The presented methodology is to apply MCDM and AHP methods in a GIS to produce an evaluation map of potential sites for offshore wind energy production.  The aim of this thesis was to determine what data is relevant and needed to translate Swedish and international standards and regulations regarding offshore wind farm siting into one or more layers of GIS data within the exclusive economic zone of Sweden. Furthermore the locations of the existing Areas of National Interests for offshore wind energy production have been evaluated using the evaluation map. The evaluation map has been obtained using several exclusionary criteria and buffer distances as well as four evaluation criteria. In addition, the results of this study have been used to calculate a potential net annual energy production for offshore wind energy in Sweden. The analysis considers some of the social, technical and environmental constraints present in offshore wind farm siting. The exclusion, buffer and evaluation criteria were determined in the initial literature review of previous studies on the topic. Datasets were collected from several different open online resources and Swedish government agencies, the analysis was performed using the QGIS software. To assess the results, the resulting evaluation map has been classified into four different categories: poor, average, good and excellent. The analysis shows that it is possible to translate Swedish and international standards into one layer of GIS data. Furthermore the results of this study show that 52% of the defined Areas of National Interest for offshore wind energy production should not be considered for wind farm siting according to the exclusion constraints, additionally only 19% of the Areas of National Interest for offshore wind energy production are classified as good or excellent. In contrast, 20.3% of the entire study area is deemed to be suitable for offshore wind farm siting, out of which 62.7% is classified as good or excellent. The potential net annual energy production has been estimated to be 56.1 TWh annually within the Areas of National Interest for offshore wind energy production and 915.3 TWh annually within the entire study area. / Sverige har en stor potential för produktion av havsbaserad vindkraft. När teknologin utvecklas och de politiska förutsättningar förändras, kommer konstruktionen av havsbaserad vindkraft i landet troligtvis öka. Den presenterade metodologin går ut på att använda MCDM och AHP metoder i ett GIS för att producera en utvärderingskarta för potentiella platser att producera havsbaserad vindenergi.  Målet med den här studien har varit att ta reda på vilken data som krävs och är relevant för att överföra svensk samt internationell standard och regler kring placeringen av havsbaserad vindkraft till ett eller flera lager av GIS data inom Sveriges exklusiva ekonomiska zon. Vidare har de existerande riksintressena för havsbaserad vindkraft utvärderats med hjälp av utvärderingskartan. Denna karta har blivit framtagen med hjälp av flertalet buffertzoner samt exkluderings- och fyra stycken utvärderingskriterier. Slutligen har studiens resultat används för att beräkna en potentiell årlig energiproduktion för offshore vindkraft i Sverige. Studien beaktar några av de sociala, tekniska och miljömässiga begränsningar som finns för havsbaserad vindenergi. Buffertzonerna samt exkluderings- och utvärderingskriterierna har bestämts med hjälp av en inledande litteraturstudie av tidigare forskning på ämnet. Den datan som använts i analysen har inhämtats från flera olika öppna onlineresurser samt från svenska myndigheter. Den efterföljande analysen har genomförts med hjälp av programmet QGIS. För att möjliggöra en kvantifiering av resultaten har utvärderings kartan omklassificerats till fyra olika kategorier: “poor”, “average”, “good” samt “excellent”. Studien visar att det är möjligt att överföra svensk samt internationell standard och regler till ett lager av GIS data. Resultatet visar att att enbart 48% av arean inom de definierade riksintressena för havsbaserad vindkraft bör beaktas vid allokering av havsbaserad vindenergi, enligt de begränsningar som definierats i denna studie. Vidare påvisar resultatet att enbart 19% av arean inom de utpekade riksintressena för vindkraft kan klassificeras som “good” eller “excellent”. Samtidigt påvisar studien att 20.3% av studieområdet bedöms som lämpligt för allokering av havsbaserad vindkraft, av dessa lämpliga områden klassificeras 62.7% som “good” och “excellent”. Den potentiella årliga energiproduktionen uppskattas till 56.1 TWh inom riksintressena för havsbaserad vindkraft samt till 915.3 TWh inom hela studieområdet.
33

地方派系、社會運動與環境治理:以八輕在雲、嘉設廠決策分析為例 / Local Faction, Social Movement and Environmental Governance: Taking the 8th Naphtha Cracking Project for Example.

呂季蓉, Lu,Chi-Jung Unknown Date (has links)
八輕的興建由於具備提振經濟發展的功能,受到熱烈歡迎;卻也因為其對環境生態影響甚鉅,引發當地居民的反對聲浪,以及全國各地的環保團體串連抗議,導致進度延宕。這種經濟與環保衝突的鄰避型設施,在廠址的選擇上,因為必須要滿足社會大眾的需求,而成為環境決策相當重要的一環。只是,同樣渴望經濟發展的雲林縣與嘉義縣,為何八輕最後會選擇落腳雲林而非嘉義?決策過程中的利害關係人又是如何互動?研究結果發現,雖然政商聯盟在中央決策場域上佔有優勢,然廠址抉擇的關鍵仍在於地方的政治生態。嘉義黃林兩派對立的政治生態,讓主政黃派在爭取開發案上,因受到林派為反對而反對的掣肘,中油倍感經營不易而退出;在雲林張派獨大的情形下,沒有足以抗衡的反對勢力,而有利於八輕的進駐。此外,無論在中央或地方的層級,環保團體都企圖在政治力的夾縫中求生存,以阻擋政商聯盟的不正義開發。地方民眾則因利益不同而選擇與派系或環保團體結盟。 / The building of 8th Naphtha Cracking Project is so popular because of its function of promoting economic development. However, local residents have great opposition to it because of its giant influence on environment. Furthermore, the series of representations from the environmental groups have made the work progress at a very low pace. The siting of nimby facility which causes the conflict between economic development and environment protection has become an important part of decision making because it has to satisfy all kinds of needs in the society. Then, we may wonder why 8th Naphtha Cracking Project chooses Yun-lin County instead of Chia-yi County since both of them are eager to develop their own economics, and how the stakeholders interact during the decision making process. The study finds out that politicoeconomic coalitions control the national political arena, and they seem to monopolize decision making process. But the local political ecology is the key to siting. In Chia-yi County, Huang Faction is in confrontation with Lin Faction. Although Huang Faction makes efforts to win the developing project, Lin Faction just protests without particular reasons. Finally, CPC gives up the project because it is so difficult to run business in this situation. On the other hand, Chang Faction is so dominant that there is no political opposition movement in Yun-lin County. And that fosters the coming of 8th Naphtha Cracking Project. In addition, no matter in central or local level, environmental groups try to influence policy to prevent the unjust development from politicoeconomic coalitions. And the local residents enter into strategic coalitions with factions or environmental groups due to different interests.
34

Towards multidisciplinary design optimization capability of horizontal axis wind turbines

McWilliam, Michael Kenneth 13 August 2015 (has links)
Research into advanced wind turbine design has shown that load alleviation strategies like bend-twist coupled blades and coned rotors could reduce costs. However these strategies are based on nonlinear aero-structural dynamics providing additional benefits to components beyond the blades. These innovations will require Multi-disciplinary Design Optimization (MDO) to realize the full benefits. This research expands the MDO capabilities of Horizontal Axis Wind Turbines. The early research explored the numerical stability properties of Blade Element Momentum (BEM) models. Then developed a provincial scale wind farm siting models to help engineers determine the optimal design parameters. The main focus of this research was to incorporate advanced analysis tools into an aero-elastic optimization framework. To adequately explore advanced designs with optimization, a new set of medium fidelity analysis tools is required. These tools need to resolve more of the physics than conventional tools like (BEM) models and linear beams, while being faster than high fidelity techniques like grid based computational fluid dynamics and shell and brick based finite element models. Nonlinear beam models based on Geometrically Exact Beam Theory (GEBT) and Variational Asymptotic Beam Section Analysis (VABS) can resolve the effects of flexible structures with anisotropic material properties. Lagrangian Vortex Dynamics (LVD) can resolve the aerodynamic effects of novel blade curvature. Initially this research focused on the structural optimization capabilities. First, it developed adjoint-based gradients for the coupled GEBT and VABS analysis. Second, it developed a composite lay-up parameterization scheme based on manufacturing processes. The most significant challenge was obtaining aero-elastic optimization solutions in the presence of erroneous gradients. The errors are due to poor convergence properties of conventional LVD. This thesis presents a new LVD formulation based on the Finite Element Method (FEM) that defines an objective convergence metric and analytic gradients. By adopting the same formulation used in structural models, this aerodynamic model can be solved simultaneously in aero-structural simulations. The FEM-based LVD model is affected by singularities, but there are strategies to overcome these problems. This research successfully demonstrates the FEM-based LVD model in aero-elastic design optimization. / Graduate / 0548 / pilot.mm@gmail.com
35

Spatial modelling of sustainable wind power development

Andersson, Martin January 2021 (has links)
Measures to mitigate climate change has never been a more pressing matter thanit is today and the global debate over energy security, environmental decline andlimited resources is heated, which motivates decision makers and leaders to searchfor alternative energy sources, renewable sources. The Swedish government has seta goal to make its entire domestic electricity production 100 % renewable and phaseout energy production based on fossil fuels entirely by year 2040, where wind powerwill contribute largely to that goal. This study aimed to generally analyse where itwas suitable and not suitable to establish wind turbines with respect to ecological,social and economical values to achieve sustainable development.To do this, a multi-criteria analysis was conducted based on the analytical hierarchyprocess method with the extension of combining it with fuzzy triangular numbersand then comparing the two methods. Ecological values were set as protected areasand not suitable for wind turbine placement. Relevance of social and economicalvalues in relation to each other were differentiated by asking five experts in the fieldof wind power as renewable energy to perform a pairwise comparison between eightdifferent factors. This resulted in relative weights illustrating the importance ofeach factor. These weights were then brought into a GIS environment where theywere modelled for suitability along with areas subjected to formal protection andother land use acting as constraints in Ragunda municipality and Västernorrlandcounty. Different scenarios were modelled that did or did not include areas forreindeer husbandry as a constraint. The final suitability maps were then comparedto existing wind turbines as well as areas of national interest for wind power inSweden.Results showed that good wind conditions was the most prominent factor to consider when siting wind turbines. No significant difference was observed when fuzzyanalytical hierarchy process was used instead of the classic analytical hierarchy process when modelling suitable wind turbine placement in a GIS environment. Ananalytical methodology combined with multi-criteria analysis applied in this studyshow that potential suitable areas that has not yet been exploited by wind powerexists both in Ragunda and Västernorrland that takes into account ecological, socialand economic criteria to support sustainable development. / Åtgärder för att förhindra klimatförändring har aldrig varit en mer angelägen frågaän den är idag och den globala debatten om energisäkerhet, miljöförstöring och begränsade resurser har väckt intresset hos många världen runt att påverka beslutsfattareoch ledare att titta på alternativa energikällor, förnybara källor. Svenska regeringenhar som mål att göra hela sin inhemska elproduktion till 100 % återförnybar ochfasa ut energiproduktion baserad på fossila bränslen helt till år 2040, där vindkrafttill stor del kommer att bidra till det målet. Denna studie syftade till att översiktligtanalysera var vindkraft är lämplig och inte lämplig att lokalisera med avseende påekologiska, sociala och ekonomiska värden för hållbar utveckling.För att göra detta genomfördes en multikriterieanalys baserad på metoden ’analytical hierarchy process’ med förlängningen av att kombinera den med ’fuzzy triangularnumbers’. Ekologiska värden sattes som skyddade områden ej lämpliga för etableringav vindkraft. Relevans av ekonomiska och sociala värden i förhållande till varandradifferentierades genom att tillfråga fem sakkuniga yrkesutövare inom vindkraftsområdet att göra en parvis jämförelse mellan åtta olika faktorer. Denna jämförelseresulterade i relativa viktningar som illustrerar vikten av varje faktor. Dessa vikter fördes sedan in i en GIS-miljö där de modellerades för lämplighet tillsammansmed områden som har formellt skydd och annan markanvändning vilket fungeradesom begränsade områden i Ragunda kommun och Västernorrlands län. Olika scenarier modellerades som inkluderade eller inte inkluderade områden för renskötselsom ett begränsningsområde. De slutliga lämplighetskartorna jämfördes sedan medbefintliga vindkraftverk samt områden av riksintresse för vindkraft i Sverige.Resultaten visade att goda vindförhållanden var den mest framträdande faktorn attta hänsyn till vid placering av vindkraftverk. Ingen större skillnad observerades nären ’fuzzy analytical hierarchy process’ användes istället för den klassiska ’analyticalhierarchy process’ när lämplig lokalisering av vindkraftverk modellerades i en GISmiljö. En analytisk metodik med hjälp av multikriterieanalys som applicerades i denhär studien visar på potentiellt lämpliga områden som ännu inte har utnyttjats avvindkraft finns både i Ragunda och Västernorrland som tar hänsyn till ekologiska,sociala och ekonomiska kriterier för att stödja hållbar utveckling. / Vindval
36

Colerain Township Zoning Amendment Case: ZA2006-04

McMahan, Kevin Joseph 28 June 2007 (has links)
No description available.
37

Ecosystem-Based Management and Refining Governance Of Wind Energy in the Massachusetts Coastal Zone: A Case Study Approach

Kumin, Enid C. 22 September 2015 (has links)
No description available.
38

A Comparative Study on Two Offshore Wind Farm Siting Approaches in Sweden / En jämförande studie av två tillvägagångssätt för siting av havsbaserade vindkraftsparker i Sverige

Nyberg, Anders, Sundström, Oskar January 2023 (has links)
This study aims to explore the ability of a multi-criteria decision making with analytical hierarchy process (MCDM-AHP) model to emulate the results of a cost benefit analysis (CBA) model in the context of offshore wind farm siting within the Swedish exclusive economic zone (EEZ). The research question addressed is whether the MCDM-AHP analysis produces similar results to the CBA analysis. In addition to this, the strengths and weaknesses of each model is explored. The MCDM-AHP model employs the spatial criteria in a more basic manner compared to the CBA model, simplifying the evaluation process while still explaining 89.5% of the variation in the CBA model and defining similar areas as suitable. Thus, it can be concluded that the MCDM-AHP model adequately emulates the CBA model within the context of offshore wind farm siting within the Swedish EEZ. However, it is crucial to note that the two models produce outputs on different scales. While the CBA model provides levelized cost of energy (LCOE) values that can be thresholded for investment viability comparisons, the suitability score generated by the MCDM-AHP model remains a relative and arbitrary score within the model. Both models entail uncertainties, limiting their usage beyond making general assumptions or identifying areas of interest. The findings reveal that the CBA model demonstrates greater robustness when confronted with changes in spatial input parameters compared to the MCDM-AHP model. This discrepancy is attributed to the iterative computation process and consideration of flat cost inputs in the CBA model, whereas the MCDM-AHP model represents a linear combination of various spatial parameters. However, the calculated LCOE values in the CBA model are highly sensitive to changes in modeling assumptions regarding external parameters, resulting in significant linear variations. The LCOE values obtained from the CBA model baseline case fall within a range of 52.1 - 98.9 EUR/MWh, which aligns with similar studies, validating the CBA model. Nonetheless, caution should be exercised when considering these results as an accurate representation of the real world due to inherent uncertainties in cost inputs and the LCOE measure. The strengths of the MCDM-AHP model lie in its robustness when the order of relative importance remains stable for key spatial evaluators. It is sensitive to significant changes in water depth and wind speed, which heavily influence its output. The model's simplicity allows for a quick overview of the problem, but it requires assumptions that introduce uncertainties. Validation of the MCDM-AHP model using existing and planned offshore wind farms within the Swedish EEZ was possible but limited by the arbitrary scale and limited validation areas. The comparison between the two models could be enhanced with more comprehensive spatial and economic data for an in-depth CBA model, which could serve as a ground truth for the MCDM-AHP model. Nevertheless, the comparison made in this study considers the CBA model to be closer to the truth, acknowledging the underlying assumptions that should be considered during evaluation. In conclusion, within the context of offshore wind farm siting, the MCDM-AHP model produces outputs that are similar to the CBA model.

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