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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.
181

Gis-based Site Selection Approach For Wind And Solar Energy Systems: A Case Study From Western Turkey

Aydin, Nazli Yonca 01 July 2009 (has links) (PDF)
Many countries around the world integrated Renewable Energy Systems (RES) in their future energy plans in order to reduce negative impacts of fossil fuel consumption on the environment. However, RES may as well cause various environmental problems which are mostly related with the geographic locations of these facilities. The aim of this thesis is to create a Geographic Information System-based methodology for evaluating alternative locations for wind, solar and hybrid power plants by using fuzzy multi-criteria decision making. Environmental objectives and economical feasibility criteria for wind and solar systems are identified through Turkish legislations, previous studies, and interviews with General Directorate of Electrical Power Resources Survey and Development. Individual satisfaction degrees for each alternative location with respect to the identified environmental objectives and economical feasibility criteria are calculated using fuzzy set theory tools. Then these individual satisfaction degrees are aggregated into overall performance indexes which are used to determine priority maps for wind and solar energy generation facilities. Finally, maps of priority sites for wind and solar energy systems are overlaid to identify suitable locations for hybrid wind-solar energy systems. The proposed methodology is applied on a case study area composed of USak, Aydin, Denizli, Mugla, and Burdur provinces.
182

Development Of A Web Gis-based Tsunami Inundation Mapping Service / A Case Study For Marmara Sea Region

Ayca, Aykut 01 June 2012 (has links) (PDF)
Tsunamis, as the catastrophic disasters, can cause loss of live and property when they come to the shores. Preparation of emergency plans is essential to reduce the damage. Consequently, any initiative in tsunami modeling and inundation mapping is of vital importance for progressing safety surveillance and maintenance. In an effort to achieve a thorough analysis of effect of tsunami, it is critical to estimate the geographical extent of possibly affected area and to predict tsunami impacts. The inundation mapping system also must serve to manage the simulation data in a scalable environment to reach end-users in the time of event. For this purpose, in this study, the generation of a Web based Geographic Information System (GIS) to serve inundation maps through web. The research methodology consists of four main stages: (i) simulating tsunamis based on six different scenarios (ii) processing simulation data through a GIS application / (iii) development of web interfaces and implementation of the developed model for Web-GIS application / (iv) verification of the created model for Marmara Sea Region. The proposed system is expected to be an efficient tool for improving inundation mapping efforts for expected tsunamis in Turkey.
183

An Examination of the Impacts of Urbanization on Green Space Access and Water Resources: A Developed and Developing World Perspective

Wright Wendel, Heather E. 01 January 2011 (has links)
This dissertation addresses the impact of urbanization and land use change on the availability and accessibility of two urban amenities that are often inequitably distributed: green space and water features. Diverse methodologies were utilized in order to gain a better understanding of the role of these amenities in improving urban quality of life and integrated water management. Using an interdisciplinary approach, this research provides a unique perspective within both a developed and developing world context by evaluating aspects of urbanization to emphasize more sustainable and integrated approaches to development. A preliminary analysis highlights potential drivers of green space revitalization in Santa Cruz, Bolivia by identifying perceived benefits of brownfields redevelopment projects between developed and developing countries. These include environmental benefits (creation of green space, reduced health risks), economic benefits (job creation, retention of residents and businesses), and social benefits (community enhancement, improved city services). Building on this analysis, an in-depth anthropological study then examines the preferences, perceptions, and barriers to accessing green spaces in Santa Cruz. Utilizing qualitative and quantifiable research methods, it was determined that although green spaces can help ensure greater equality in urban areas by providing access to public spaces, significant gender discrepancies were noted in Santa Cruz. Disparities in the distribution and accessibility of green space and water features were further assessed in Tampa, Florida. Using a Geographic Information System (GIS) and census data, access to these urban amenities was examined. The inner-city community of East Tampa was found to have greater inequalities, relative to other areas in Tampa, in terms of the quality, diversity, and size of green spaces within their community. The revitalization of urban water infrastructures, such as stormwater ponds, was evaluated as a way to address these environmental justice issues. Lastly, impacts of urbanization, land use change, and population growth on water resources were analyzed using a regional water balance model for the city of Santa Cruz. Development scenarios were examined based on historical and future spatial and temporal changes. Between 1970 and 2010, a decreasing trend was observed for the aridity index (potential evapotranspiration over precipitation) while future climate projections (2011-2050) indicate a trend reversal, with the IPCC's emission scenario A1B having the strongest increasing trend. The increasing trend in the aridity index suggests a long-term shift in the regional hydroclimatology towards less humid conditions. Each chapter of this research builds on the idea of green space as an indicator of urban quality of life (particularly for urban poor who rely more heavily on public spaces for leisure and recreation activities) as well as an important facilitator of urban hydrology due to their predominately permeable surfaces (including water features). Yet rapid change occurring in cities around the world has resulted in the under-valuation of both green space and water resources and thus these amenities have been degraded or destroyed through the urbanization process.
184

Assessing GIS-based indicator methodology for analyzing the physical vulnerability of water and sanitation infrastructure

Karlson, Martin January 2012 (has links)
Climate related problems such as droughts, heat waves, increased levels of precipitation and storms threaten the functionality of several infrastructural systems. This thesis focus on infrastructure that provides for water and sanitation services because it has been identified as being particular at risk when the climate is changing. The identification and mapping of the vulnerability of a system can improve the prerequisites to choose more appropriate measures to facilitate the situation at hand. In this study a set of GIS based methodologies using indicators (simple and composite) of vulnerability are proposed and assessed. “Physical” vulnerability is used as a measure combining the intrinsic characteristics of a system and the climate related hazard resulting in a measure for physical vulnerability. GIS software is used to manage the spatial data sets and to combine the indicators into indexes of physical vulnerability. The assessed systems and related climate hazards are: - Water and sewage pipe network and an increased risk of pipe breakage due to increased frequencies of landslides and – An increased risk for ground and surface water supplies related to pollution from the point sources sewage infiltration and polluted ground”. The resulting GIS applications are tested on pilot areas located in the Stockholm region and GIS based sensitivity analyses are performed. The availability and accessibility of relevant digital spatial data is also assessed and discussed.
185

Sustainable Transportation Decision-Making: Spatial Decision Support Systems (SDSS) and Total Cost Analysis

Kim, Hwan Yong 03 October 2013 (has links)
Building a new infrastructure facility requires a significant amount of time and expense. This is particularly true for investments in transportation for their longstanding and great degree of impact on society. The scope of time and money involved does not mean, however, we only focus on the economies of scale and may ignore other aspects of the built environment. To this extent, how can we achieve a more balanced perspective in infrastructure decision-making? In addition, what aspects should be considered when making more sustainable decisions about transportation investments? These two questions are the foundations of this study. This dissertation shares its process in part with a previous research project – Texas Urban Triangle (TUT). Although the TUT research generated diverse variables and created possible implementations of spatial decision support system (SDSS), the methodology still demands improvement. The current method has been developed to create suitable routes but is not designed to rank or make comparisons. This is admittedly one of the biggest shortfalls in the general SDSS approach, but is also where I see as an opportunity to make alternative interpretation more comprehensive and effective. The main purpose of this dissertation is to develop a Spatial Decision Support System (SDSS) that will lead to more balanced decision-making in transportation investment and optimize the most sustainable high-speed rail (HSR) route. The decision support system developed here explicitly elaborates the advantages and disadvantages of a transportation corridor in three particular perspectives: construction (fixed costs); operation (maintenance costs); and externalities (social and environmental costs), with a specific focus on environmental externalities. Considering more environmental features in rail routing will offset short-term economic losses and creates more sustainable environments in long-term infrastructure planning.
186

Soil Erosion Risk Mapping Using Geographic Information Systems: A Case Study On Kocadere Creek Watershed, Izmir

Okalp, Kivanc 01 December 2005 (has links) (PDF)
Soil erosion is a major global environmental problem that is increasing year by year in Turkey. Preventing soil erosion requires political, economic and technical actions / before these actions we must learn properties and behaviors of our soil resources. The aims of this study are to estimate annual soil loss rates of a watershed with integrated models within GIS framework and to map the soil erosion risk for a complex terrain. In this study, annual soil loss rates are estimated using the Universal Soil Loss Equation (USLE) that has been used for five decades all over the world. The main problem in estimating the soil loss rate is determining suitable slope length parameters of USLE for complex terrains in grid based approaches. Different algorithms are evaluated for calculating slope length parameters of the study area namely Kocadere Creek Watershed, which can be considered as a complex terrain. Hickey&amp / #8217 / s algorithm gives more reliable topographic factor values than Mitasova&amp / #8217 / s and Moore&amp / #8217 / s. Satellite image driven cover and management parameter (C) determination is performed by scaling NDVI values to approximate C values by using European Soil Bureau&amp / #8217 / s formula. After the estimation of annual soil loss rates, watershed is mapped into three different erosion risk classes (low, moderate, high) by using two different classification approaches: boolean and fuzzy classifications. Fuzzy classifications are based on (I) only topographic factor and, (II) both topographic and C factors of USLE. By comparing three different classified risk maps, it is found that! in the study area topography dominates erosion process on bare soils and areas having sparse vegetation.
187

利用自由軟體建構森林資源調查WebGIS之研究

柯景騰, Ko, Ching-Teng Unknown Date (has links)
台灣因地理位置、氣候與地形等因素,孕育了豐富的森林資源。林務局廣設永久樣區以瞭解森林資源之分布與蓄積情形,永久樣區每隔五年進行全面性調查,調查所得資料繁多,惟永久樣區之植物資源調查資料僅記錄樣區之坐標位置與樣區內植物之分布情形,並未建立相關圖面資料,以至於無法與其他圖籍資料進行套疊分析。 本研究以MapServer、Zope等自由軟體與自行開發之軟體工具,處理圖形與相關屬性資料,以建構符合OGC(Open Geospatial Consortium)提出之網路地圖服務(Web Map Service,WMS)與網路圖徵服務(Web Feature Service,WFS)規格的WebGIS伺服端系統,並且整合各項森林資源表簿調查資料與圖籍資料,建構一包含森林永久樣區與樣木之空間與屬性資料的森林資源調查管理系統,以提供管理者經營管理與規劃之良好工具。 / There are plentiful forest resources in Taiwan because of the unique geographic location, climate and terrain. In order to acquire the information of distribution and storage of forest resources, the Forest Bureau sets up a lot of sample plots, and these sample plots will be fully surveyed every five years. Numerous data were collected, however only the coordinates of sample plots and the distribution of vegetation within those sample plots were recorded. It is not possible to perform map overlay analysis with the other map data because of lacking spatial data of sample plots. In this research, a WebGIS (web-based GIS) system was developed entirely from free software including MapServer, Zope, Apache and PostgreSQL/PostGIS. This WebGIS system is based on the OGC OpenGIS architecture (WMS and WFS), therefore it is easy to share geospatial data with the other GIS systems for various applications. Furthermore, a forest resources management system was established, which integrates the attribute data from field investigation and generates spatial data of sample plots and sample trees automatically.
188

Small area market demand prediction in the automobile industry

Lu, Hongwei, Marketing, Australian School of Business, UNSW January 2008 (has links)
The general aim of this research is to investigate approaches to: •improve small area market demand (i.e. SAMD) prediction accuracy for the purchase of automobiles at the level of each Census Collection District (i.e. CCD); and •enhance understanding of meso-level marketing phenomena (i.e. geographically aggregated phenomena) relating to SAMD. Given the importance of SAMD prediction, and the limitations posed by current methods, four research questions are addressed: •What are the key challenges in meso-level SAMD prediction? •What variables affect SAMD prediction? •What techniques can be used to improve SAMD prediction? •What is the value of integrating these techniques to improve SAMD prediction? To answer these questions, possible solutions from two broad areas are examined: spatial analysis and data mining. The research is divided into two main studies. In the first study, a seven-step modelling process is developed for SAMD prediction. Several sets of models are analysed to examine the modelling techniques’ effectiveness in improving the accuracy of SAMD prediction. The second study involves two cases to: 1) explore the integration of these techniques and their advantages in SAMD prediction; and 2) gain insights into spatial marketing issues. The case study of Peugeot in the Sydney metropolitan area shows that urbanisation and geo-marketing factors can have a more important role in SAMD prediction than socio-demographic factors. Furthermore, results show that modelling spatial effects is the most important aspect of this prediction exercise. The value of the integration of techniques is in compensating for the weaknesses of conventional techniques, and in providing complementary and supplementary information for meso-level marketing analyses. Substantively, significant spatial variation and continuous patterns are found with the influence of key studied variables. The substantive implications of these findings have a bearing on both academic and managerial understanding. Also, the innovative methods (e.g. the SAMD modelling process and the model cube based technique comparison) developed from this research make significant contributions to marketing research methodology.
189

Consolidação do uso agropecuário em área de reserva legal: uma proposta metodológica de aplicação do Art. 68 do Código Florestal (Lei nº 12.651/2012) / Consolidation of agricultural use in areas of legal reserve: a methodological approach for the application of Article 68 of Forest Code (Law no. 12.651/2012)

Emanoel Junior da Silva Nunes 27 August 2014 (has links)
A exploração indiscriminada da vegetação natural e sucessivas alterações nas leis ambientais contribuíram para colocar grande parte dos produtores rurais em situação irregular no Brasil. Em 2012 após dois anos de negociações, o parlamento brasileiro aprovou novas mudanças no Código Florestal, que reduziu o passivo de vegetação natural acumulado. Entretanto, publicações recentes indicam que, mesmo com as novas alterações, o país ainda apresenta o passivo entre 17 e 21 Mha (milhões de hectares) que precisa ser recomposto. A redação atual do Código Florestal criou uma nova alternativa de regularização por meio de um dispositivo legal (Art. 68 - Lei Federal nº 12.651/2012), que permite avaliar a conformidade das áreas agrícolas de acordo com a lei em vigor no período de abertura da terra. Os possíveis resultados desse dispositivo sobre o passivo ambiental é, no entanto, ainda desconhecido. Objetivou-se com esse trabalho desenvolver uma metodologia capaz de relacionar os principais anos em que ocorreram mudanças nas leis ambientais com a abertura de novas áreas agropecuárias, sobretudo expor os possíveis cenários desse dispositivo sobre o passivo em RL, por meio de modelagem e geoprocessamento. A metodologia foi dividida em duas etapas complementares. Na primeira etapa estimou-se o passivo de vegetação natural nos imóveis rurais, de acordo com o Código Florestal, e na segunda etapa metodológica reconstruiu-se o histórico do uso das terras para o período entre 1940 e 2001 e aplicou-se as restrições legais em diferentes décadas. Foram avaliados quatro períodos (antes de 1934, 1934-1965, 1965-1989 e 1989-2001), sob dois cenários (considerar e não considerar as pastagens naturais), bem como um cenário de isenção na proteção da vegetação nativa no bioma Cerrado para o período (1965-1989). As pastagens naturais se consideradas como vegetação nativa restrita ao uso, influenciam diretamente a necessidade de recomposição, principalmente nas regiões Sul e Sudeste. Os resultados obtidos indicam um cenário potencial (máximo e mínimo) de redução na área a ser recomposta de vegetação nativa em Reserva Legal. Do passivo atual de 15,2 Mha calculado na primeira etapa, pode ser reduzido em no máximo 79% e no mínimo 52% com o dispositivo legal (Art. 68). / The indiscriminate exploitation of natural vegetation and several changes in environmental laws contributed to place a large number of rural producers in an illegal condition in Brazil. In 2012 after two years of negotiations, the Brazilian parliament approved new changes on the Forest Code, which had the effect of reducing the liability of natural vegetation accumulated. However, recent publications indicate that, even with the new changes, the country still presents a liability between 17 and 21 Mha (millions hectares) that requires reset. The current wording of forest code created a new alternative of regularization through a legal device (Art. 68 - Federal Law no. 12.651/2012), which allows the evaluation of agricultural areas compliance according to law in effect at the time of land clearing. The possible outcomes of this device on current environmental liability is, nevertheless, still unknown. The aim of this study was to develop a methodology able of relate the main years that occurred changes in environmental laws with the opening of new agricultural areas, especially to expose potential scenarios that device over liabilities in LR, through modeling and geoprocessing. The methodology was divided into two complementary steps. The first step estimates liability of natural vegetation in private areas according to current environmental legislation, and the second methodological step reconstructs historical land use for the period 1940-2001 and implement legal restrictions in different decades. We evaluated four periods (before 1934, 1934-1965, 1965-1989 and 1989-2001) under two scenarios (consider and not consider the natural pastures), as well as a scenario for exemption the Cerrado biome from native vegetation protection for the period (1965 - 1989). The natural pastures if considered as native vegetation directly influence the need for restoration, especially in the South and Southeast regions. Results indicate a potential (maximum and minimum) scenario reduction in the area of vegetation to be restored in legal reserve. The current liability of 15.2 Mha calculated in the first step is reduced a maximum of 79% and a minimum of 52% by using the (Art. 68) legal device.
190

ANÁLISE TEMPORAL E ESPACIAL DE CONDENAÇÕES DE FRANGOS EM UM MATADOURO-FRIGORÍFICO

Giotto, Diana Bertani 26 February 2008 (has links)
This study aims to make a temporal and spatial analysis of condemnation post mortem partial and total of chickens in a slaughterhouse of Federal inspection located in the West of Santa Catarina. The data basis used in the presented study was daily register of occurrences of condemnation of chickens in the period that starts in september, 2006 and goes until august, 2007 following the criteria of sentences stetted by the Federal Inspection Service. Descriptive analysis based on measures of frequency distribution and tendency analysis through time series techniques with the use of moving average was defined to the temporal analysis of condemnations. The special analysis was accomplished trough Geographic Information System (GIS) for the store, organization and manipulation of the Federal inspection data, as well as the use of geographic coordinates (latitude and longitude) of each production s unit and the georreferenced map from the study s area to the specialization of the producers and from the pathological condemnation that has higher occurrence. The results demonstrated that the temporal analysis of the condemnation through moving average for the gathering of three to three months diminish data s dispersion in the distribution of the monthly frequency and define best the tendency of each factor of condemnation studied. In the spatial analysis, SIG allowed the specific localization from each producer, the origin of the lots slaughtered, the incidence in which the condemnation occurred in each lot, spatial localization from each condemnation, the viewing form the areas of higher concentration and intensity and also the monthly behavior that every pathology presented. / Este trabalho teve como objetivo realizar uma análise temporal e espacial de condenações post mortem parciais e totais de frangos em um matadouro-frigorífico de Inspeção Federal localizado na região Oeste do estado de Santa Catarina. Os dados utilizados na presente pesquisa foram registros de ocorrências diárias de condenações de frangos no período de setembro de 2006 à agosto de 2007, obedecendo aos critérios de condenações estipulados pelo S.I.F (Serviço de Inspeção Federal). Analises descritiva com medidas de distribuição de freqüência e análises de tendência por meio de técnicas de séries temporais com uso de médias móveis foram realizadas para a análise temporal das condenações. Para a análise espacial foi utilizado um Sistema de Informações Geográficas (SIG) para o armazenamento, organização e manipulação dos dados do S.I.F., bem como a utilização das coordenadas geográficas (latitude e longitude) de cada unidade de produção e o mapa georreferenciado da região de estudo para a espacialização dos produtores e das condenações patológicas de maior ocorrência. Os resultados obtidos demonstraram que a análise temporal das condenações através das médias móveis pelo agrupamento de três em três meses diminuíram a dispersão dos dados na distribuição de freqüência mensal e definiram melhor a tendência de cada fator de condenação estudado. Na análise espacial, o uso do SIG permitiu localização pontual de cada produtor integrado, origem dos lotes abatidos, incidência em que as condenações ocorreram em cada lote, localização espacial de cada condenação, visualização de áreas de maior concentração e intensidade e o comportamento mensal que cada patologia apresentou.

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