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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.
161

Análise espacial da mortalidade por doenças do aparelho circulatório nas regiões urbanas de Juiz de Fora - MG

Nogueira, Mário Círio 04 February 2009 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-10-05T15:24:46Z No. of bitstreams: 1 mariocirionogueira.pdf: 2341743 bytes, checksum: 751ca181e6b626c41d8a9be1725de0a9 (MD5) / Approved for entry into archive by Diamantino Mayra (mayra.diamantino@ufjf.edu.br) on 2016-10-06T12:30:12Z (GMT) No. of bitstreams: 1 mariocirionogueira.pdf: 2341743 bytes, checksum: 751ca181e6b626c41d8a9be1725de0a9 (MD5) / Made available in DSpace on 2016-10-06T12:30:12Z (GMT). No. of bitstreams: 1 mariocirionogueira.pdf: 2341743 bytes, checksum: 751ca181e6b626c41d8a9be1725de0a9 (MD5) Previous issue date: 2009-02-04 / As doenças do aparelho circulatório (DAC) são as principais causas de morte em Juiz de Fora, no Brasil e na maioria dos países do mundo. A distribuição espacial da mortalidade por DAC em grandes cidades não é homogênea: regiões com piores condições sociais têm maiores taxas de mortalidade. A mortalidade precoce por estas doenças também está relacionada às condições socioeconômicas da região de moradia. As técnicas de análise espacial em saúde permitem estudar os fatores socioambientais como possíveis determinantes de doenças no nível populacional. Dentre estes fatores, os mais utilizados são indicadores de renda, escolaridade, saneamento básico e estrutura do domicílio, obtidos dos censos demográficos decenais do IBGE. O indicador sintético Índice de Desenvolvimento Social (IDS) foi criado para comparar o desenvolvimento social de áreas geográficas de mesma natureza, sendo composto pela média aritmética de dez indicadores do censo demográfico. O objetivo deste trabalho foi analisar a distribuição espacial da mortalidade por DAC nas regiões urbanas (RU) de Juiz de Fora e sua relação com fatores socioeconômicos, especialmente o IDS. Utilizou-se delineamento ecológico, do tipo análise espacial em saúde, com as 81 RU como unidades de análise. Foram usadas técnicas exploratórias de análise de dados espaciais, como medidas de autocorrelação espacial e estimadores bayesianos empíricos. Para investigar a desigualdade na mortalidade por doenças cardiovasculares foram aplicadas as técnicas estatísticas: teste t, teste de Mann-Whitney, análise de variância, análise de correlação e análise de regressão. A relação entre mortalidade por DAC e os indicadores foi investigada com a aplicação de modelos lineares generalizados de Poisson. Devido à presença de super-dispersão, foram ajustados também modelos de quase-Poisson e binomiais negativos. Os resultados indicam que a mortalidade cardiovascular no espaço urbano de Juiz de Fora está associada às condições socioeconômicas do local de residência. A diminuição das desigualdades socioeconômicas em cidades de porte médio pode levar a reduções importantes nas iniquidades em saúde. / The cardiovascular diseases (CVD) are the main causes of death in Juiz de Fora, in Brazil and in most countries. The spatial distribution of CVD mortality in large cities is not homogeneous: regions with worse social conditions have bigger mortality rates. Premature CVD mortality is also related to socioeconomic conditions of neighborhood. The techniques of spatial analysis in health allow to study socioambiental factors as possible determinants of diseases at the population level. Amongst these factors, the most used are education, income and sanitation indicators from national census. The synthetic indicator Índice de Desenvolvimento Social (IDS) was created to compare the social development of similar geographic areas and is composed by the arithmetic mean of ten indicators of national census. The objective of this work was to analyze the spatial distribution of mortality due to CVD in urban regions (RU) of Juiz de Fora and its relationship with socioeconomic factors, especially the IDS. The design of study was ecological, subtype spatial analysis in health, with the 81 RU as units of analysis. It was employed exploratory techniques like measures of spatial autocorrelation and empirical bayesian estimators. To investigate inequalities in CVD mortality were aplied the statistic tests: t test, Mann-Whitney test, variance analysis, correlation analysis and regression analysis. The relationship between CVD mortality and socioeconomic indicators was investigted by Poisson generalized linear models. Due to over-dispersion of data, quasi-Poisson and negative binomial models were also fitted. Results indicate that CVD mortality in urban space of Juiz de Fora is associated with socioeconomic conditions of neighborhood. The reduction of socioeconomic inaqualities in middle cities could induce important reductions in health iniquities.
162

Assessing processes of long-term land cover change and modelling their effects on tropical forest biodiversity patterns – a remote sensing and GIS-based approach for three landscapes in East Africa: Assessing processes of long-term land cover change and modelling their effects on tropical forest biodiversity patterns – a remote sensing and GIS-based approach for three landscapes in East Africa

Lung, Tobias 15 July 2010 (has links)
The work describes the processing and analysis of remote sensing time series data for a comparative assessment of changes in different tropical rainforest areas in East Africa. In order to assess the effects of the derived changes in land cover and forest fragmentation, the study made use of spatially explicit modelling approaches within a geographical information system (GIS) to extrapolate sets of biological field findings in space and time. The analysis and modelling results were visualised aiming to consider the requirements of three different user groups. In order to evaluate measures of forest conservation and to derive recommendations for an effective forest management, quantitative landscape-scale assessments of land cover changes and their influence on forest biodiversity patterns are needed. However, few remote sensing studies have accounted for all of the following aspects at the same time: (i) a dense temporal sequence of land cover change/forest fragmentation information, (ii) the coverage of several decades, (iii) the distinction between multiple forest formations and (iv) direct comparisons of different case studies. In regards to linkages of remote sensing with biological field data, no attempts are known that use time series data for quantitative statements of long-term landscape-scale biodiversity changes. The work studies three officially protected forest areas in Eastern Africa: the Kakamega-Nandi forests in western Kenya (focus area) and Mabira Forest in south-eastern Uganda as well as Budongo Forest in western Uganda (for comparison purposes). Landsat imagery of in total eight or seven dates in regular intervals from 1972/73 to 2003 was used. Making use of supervised multispectral image classification procedures, in total, 12 land cover classes (six forest formations) were distinguished for the Kakamega-Nandi forests and for Budongo Forest while for Mabira Forest ten classes could be realised. An accuracy assessment via error matrices revealed overall classification accuracies between 81% and 85%. The Kakamega-Nandi forests show a continuous decrease between 1972/73 and 2001 of 31%, Mabira Forest experienced an abrupt loss of 24% in the late 1970s/early 1980s, while Budongo Forest shows a relatively stable forest cover extent. An assessment of the spatial patterns of forest losses revealed congruence with areas of high population density while a spatially explicit forest fragmentation index indicates a strong correlation of forest fragmentation with forest management regime and forest accessibility by roads. For the Kenyan focus area, three sets of biological field abundance data on keystone species/groups were used for a quantitative assessment of the influence of long-term changes in tropical forests on landscape-scale biodiversity patterns. For this purpose, the time series was extended with another three land cover data sets derived from aerial photography (1965/67, 1948/(52)) and old topographic maps (1912/13). To predict the spatio-temporal distribution of the army ant Dorylus wilverthi and of ant-following birds, GIS operators (i.e. focal and local functions) and statistical tests (i.e. OLS or SAR regression models) were combined into a spatial modelling procedure. Abundance data on three guilds of birds differing in forest dependency were directly extrapolated to five forest cover classes as distinguished in the time series. The results predict declines in species abundances of 56% for D. wilverthi, of 58% for ant-following birds and an overall loss of 47% for the bird habitat guilds, which in all three cases greatly exceed the rate of forest loss (31%). Additional extrapolations on scenarios of deforestation and reforestation confirmed the negative ecological consequences of splitting-up contiguous forest areas but also showed the potential of mixed indigenous forest plantings. The visualisation of the analysis and modelling results produced a mixture of different outcomes. Map series and a matrix of maps both showing species distributions aim to address scientists and decision makers. The results of the land cover change analysis were synthesised in a map of land cover development types for each study area, respectively. These maps are designed mainly for scientists. Additional maps of change, limited to a single class of forest cover and to three dates were generated to ensure an easy-to-grasp communication of the major forest changes to decision makers. Additionally, an easy-to-handle visualisation tool to be used by scientists, decision makers and local people was developed. For the future, an extension of this study towards a more complete assessment including more species/groups and also ecosystem functions and services would be desirable. Combining a framework for land cover simulation with a framework for running empirical extrapolation models in an automated manner could ideally result in a GIS-based, integrated forest ecosystem assessment tool to be used as regional spatial decision support system. / Die Arbeit beschreibt die Prozessierung und Analyse von Fernerkundungs-Zeitreihendaten für eine vergleichende Abschätzung von Veränderungen verschiedener tropischer Waldökosysteme Ostafrikas. Um Effekte der Veränderungen bzgl. Landbedeckung und Waldfragmentierung auf Biodiversitätsmuster abzuschätzen, wurden verschiedene räumlich explizite Modellierungssätze innerhalb eines geographischen Informationssystems (GIS) zur räumlichen und zeitlichen Extrapolation biologischer Felderhebungsdaten benutzt. Die Visualisierung der Analyse- und Modellierungsergebnisse erfolgte unter Berücksichtigung der Bedürfnisse von drei verschiedenen Nutzergruppen. Um Waldschutzmaßnahmen zu evaluieren und Empfehlungen für ein effektives Waldmanagement abzuleiten, sind quantitative Abschätzungen von Landbedeckungsveränderungen sowie von deren Einfluss auf tropische Waldbiodiversitätsmuster nötig. Wenige fernerkundungsbasierte Studien haben jedoch bislang alle der folgenden Faktoren berücksichtigt: (i) Informationen zu Veränderungen von Landbedeckung und Waldfragmentierung in dichter zeitlicher Sequenz, (ii) die Abdeckung mehrerer Jahrzehnte, (iii) die Unterscheidung zwischen mehreren Waldformationen, und (iv) direkte Vergleiche von unterschiedlichen Fallstudien. Hinsichtlich Verknüpfungen von Fernerkundung mit biologischen Felddaten sind bisher keine Studien bekannt, die Zeitreihendaten für quantitative Aussagen zu Langzeitveränderungen von Biodiversität auf Landschaftsebene verwenden. Die Arbeit untersucht drei offiziell geschützte Gebiete: die Kakamega-Nandi forests in Westkenia (Hauptuntersuchungsgebiet) sowie Mabira Forest in Südost-Uganda und Budongo Forest in West-Uganda (zu Vergleichszwecken). Es wurden Landsat-Daten für insgesamt acht bzw. sieben Zeitpunkte zwischen 1972/73 und 2003 in ungefähr gleichen Abständen erworben. Mit Hilfe von überwachten, multispektralen Klassifizierungsverfahren wurden für die Kakamega-Nandi forests und Budongo Forest jeweils 12 Landbedeckungsklassen (sechs Waldformationen) und für Mabira Forest zehn Klassen unterschieden. Eine Genauigkeitsprüfung mit Hilfe von Fehlermatrizen ergab Gesamtklassifizierungsgenauigkeiten zwischen 81% und 85%. Die Kakamega-Nandi forests sind durch eine kontinuierliche Waldabnahme von 31% zwischen 1972/73 und 2001 gekennzeichnet, Mabira Forest zeigt einen abrupten Waldverlust von 24% in den späten 1970ern/frühen 1980ern, während die Ergebnisse für Budongo Forest eine relativ stabile Waldbedeckung ausweisen. Während eine Abschätzung der räumlichen Muster von Waldverlusten eine hohe Deckungsgleichheit mit Gebieten hoher Bevölkerungsdichte ergab, deutet die Anwendung eines räumlich expliziten Waldfragmentierungsindexes auf eine starke Korrelation von Waldfragmentierung mit der Art von Waldmanagement sowie mit der Erreichbarkeit von Wald über Straßen hin. Um den Einfluss von Langzeit-Landbedeckungsveränderungen auf Biodiversitätsmuster auf Landschaftsebene für das kenianische Hauptuntersuchungsgebiet quantitativ abzuschätzen wurden drei Datensätze mit biologischen Felderhebungen zur Abundanz von Schlüsselarten/-gruppen verwendet. Zu diesem Zweck wurde die Zeitreihe zunächst um drei weitere Landbedeckungs-Datensätze ergänzt, die aus Luftbildern (1965/67, 1948/(52)) bzw. alten topographischen Karten (1912/13) gewonnen wurden. Zur Vorhersage der raum-zeitlichen Verteilung der Treiberameise Dorylus wilverthi wurden GIS-Operatoren und statistische Tests (OLS bzw. SAR Regressionsmodelle) in einem räumlichen Modellierungsablauf kombiniert. Abundanzdaten von drei sich hinsichtlich ihrer Abhängigkeit von Wald unterscheidenden Vogelgilden wurden direkt auf fünf Waldbedeckungsklassen hochgerechnet, die in der Zeitreihe unterschieden werden konnten. Die Ergebnisse prognostizieren Abundanzabnahmen von 56% für D. wilverthi, von 58% für Ameisen-folgende Vögel und einen Gesamtverlust von 47% für die Vogelgilden, was in allen drei Fällen eine deutliche Überschreitung der Waldverlustrate von 31% darstellt. Zusätzliche Extrapolationen basierend auf Szenarien bestätigten die negativen ökologischen Konsequenzen der Zerteilung zusammenhängender Waldflächen bzw. zeigten andererseits das Potential von Aufforstungen mit einheimischen Arten auf. Die Visualisierung der Analyse- bzw. Modellierungsergebnisse führte zu unterschiedlichen Darstellungen: mit einer Reihe von nebeneinander positionierten Einzelkarten sowie einer Matrix von Einzelkarten, die jeweils Artenverteilungen zeigen, sollen Wissenschaftler und Entscheidungsträger angesprochen werden. Aus den Ergebnissen der Landbedeckungsanalyse für die drei Untersuchungsgebiete wurden Landbedeckungsveränderungstypen generiert und jeweils in einer synthetischen Karte dargestellt, die hauptsächlich für Wissenschaftler gedacht sind. Um die wesentlichen Waldveränderungen auch auf einfache Weise zu den Entscheidungsträgern zu kommunizieren, wurden zusätzliche Karten erstellt, die nur eine aggregierte Klasse „Waldbedeckung“ zeigen und jeweils auf drei Zeitschritte der Zeitreihen begrenzt sind. Zusätzlich wurde ein leicht zu bedienendes Visualisierungstool entwickelt, das für Wissenschaftler, Entscheidungsträger und die lokale Bevölkerung gedacht ist. Für die Zukunft wäre eine umfassendere Abschätzung unter Berücksichtigung zusätzlicher Arten/-gruppen sowie auch Ökosystemfunktionen und –dienstleistungen wünschenswert. Die Verknüpfung einer Applikation zur Landbedeckungsmodellierung mit einer Applikation zur Ausführung von empirischen Extrapolationsmodellen (in stärkerem Maße automatisiert als in dieser Arbeit) könnte im Idealfall in ein GIS-basiertes Tool zur integrativen Bewertung von Waldökosystemen münden, das dann als räumliches Entscheidungsunterstützungssystem verwendet werden könnte.
163

[en] AN EFFICIENT ALGORITHM FOR THE ADJACENT QUADRATIC SHORTEST PATH PROBLEM WITH APPLICATION TO SMOOTH TRANSMISSION LINE ROUTING / [pt] UM ALGORITMO EFICIENTE PARA O PROBLEMA DE CAMINHO MAIS CURTO QUADRÁTICO ADJACENTE COM APLICAÇÃO NO DESENHO DE ROTAS SUAVES DE LINHAS DE TRANSMISSÃO

JOAO MARCOS DUSI VILELA 13 January 2022 (has links)
[pt] Essa dissertação explora o problema roteamento de linhas de transmissão (LT) através da solução do caminho mais curto em um grafo sem ciclos de melhoria, considerando custos quadráticos para arcos adjacentes. Esse problema é conhecido como o Problema do Caminho Mínimo Quadrático Adjacente (CMQA). Esse trabalho apresenta uma descrição teórica do CMQA, propõe uma extensão do algoritmo Dijkstra (aqDijkstra) para solução de CMQA em tempo polinomial e discute como o algoritimo pode ser utilizado em metodologias de roteamento de LT. Em seguida, apresentamos uma melhoria estendendo o algoritmo A estrela para sua forma adjacente quadrática (aqA estrela), incluindo uma etapa de busca reversa para estimação de custos de chegada. Foram feitos experimentos computacionais contemplando a variação de custos quadráticos, geração de instâncias aleatórias, testes de estresse e comparação com abordagens já utilizadas na literatura. Os resultados sugerem que: (i) aqA estrela teve o melhor desempenho, atingindo tempos de busca 40 vezes mais rápidos que aqDijkstra e 50 vezes mais rápido que a abordagem mais rápida apresentada pela literatura; (ii) a eficiência dos algoritmos não foi afetada pela variação dos custos quadráticos; (iii) os algoritmos propostos aqA estrela e aqDijkstra também foram mais eficientes nas instancias aleatórias, reafirmando a superioridade dos mesmos. Duas aplicações são apresentadas, uma de objetivo ilustrativo e outra para um caso real. O algoritimo aqA estrela foi usado para solução de um CMQA em um grafo de quase um bilhão de arcos quadraticos, resultado em uma rota proposta com custos adicionais três vezes menor. / [en] This dissertation explores the problem of transmission line (TL) routing through finding the shortest path on an undirected graph with no improving cycles, considering quadratic costs for adjacent arcs. This problem is known as the Adjacent Quadratic Shortest Path Problem (AQSPP). This work provides the theoretical background for the AQSPP, proposes an extension of Dijkstra s algorithm (aqDijkstra) for solving AQSPP in polynomial-time and discusses how AQSPP can be included in routing methodologies. Furthermore, it is presented an improvement to the algorithm: the adjacent quadratic A star (aq A star) with a backward search for cost-togo estimation, to speed up search. For computational experiments, aqDijkstra and aqA star are benchmarked with other algorithms from the technical literature. The search behavior of the algorithms is also studied within different tests, including: quadratic cost variation, randomly generated graph instances and increasingly larger instances. The numerical results suggests that: (i) aqA star outperformed all the other algorithms, being 40 times faster than aqDijsktra and 50 times faster than the fastest benchmark algorithm; (ii) the studied algorithms do not lose efficiency as quadratic costs increase; (iii) aqA star and aqDijkstra were faster benchmark algorithms under random graph instances, indicating their robustness. Two applications are provided, one for illustrative purposes, and another to study performance on a real application. The aqA star algorithm solved an AQSSP on a graph with almost a billion quadratic arcs and provided a route with three times lower additional costs.
164

Participatory mapping and the use of GIS for sustainable land use planning in the Hardap Region, Namibia

Mundia, Lisho Christoh 08 1900 (has links)
Namibia, like most developing countries, lacks complete and comprehensive sustainable land use plans. This has a negative impact on a range of land use activities. Although Geographical Information System (GIS) is used as a planning tool in Namibia in an ad hoc manner, there is no broader comprehensive framework to guide applications of GIS as a planning tool specifically for land use planning (LUP). The purpose of this study is to demonstrate how integration of participatory mapping and GIS can be used to enhance land use planning in the Hardap Region, Namibia. The study seeks to point out lack of local communities’ engagement in LUP process; lack of policy frameworks and guidelines for Integrated Land Use Planning (ILUP); and poor data management. The study adapted quantitative and qualitative approaches to collect relevant data and information related to LUP. Data collected using participatory approaches such as Focus Group Discussion (FGD), Participatory Rural Appraisal (PRA) and Strengths Weaknesses Opportunities and Threats (SWOT) analysis were applied in an integrated manner in various contexts. FGDs were used to evaluate participants’ knowledge of LUP in the Hardap region. Besides participating in the FGDs, PRA and SWOT analysis, the participants also expressed opinions concerning desirable and undesired land uses in the region. Sketch and photo- mapping methods were found to be suitable approaches to capture local knowledge. GIS was found to be effective in integrating participatory maps produced by the local communities and existing spatial land use data. The results shows that local communities are eager to learn about participatory approaches and are willing to share their views and knowledge on land use in their respective areas. A user-friendly comprehensive georeferenced digital database was created for the Hardap region. This database is used for spatial data management, analyses, maintenance and production of maps. Maps of new development initiatives in the region were produced. The frameworks and guidelines suggested in this study has the potential to guide participatory techniques aided by GIS technology involving local communities in sustainable LUP processes in Namibia. The digital database incorporates experts’ knowledge on the users and implementation aspects, making it a LUP benchmark tool of Namibia. Key recommendations include incorporation of GIS technology in the ILUP, implementation of comprehensive participatory LUP, adoption of guidelines for future LUP, skills training and capacity development, and result-based monitoring. / Geography / D. Litt. et Phil. (Geography)
165

Αποτύπωση υποθαλάσσιων πολιτιστικών στοιχείων και βιολογικών πόρων στην παράκτια ζώνη της νήσου Λέρου / Marine geophysical survey for cultural and habitat mapping in the coastal zone of Leros island, Aegean sea, Greece

Κάτσου, Ευγενία 11 July 2013 (has links)
Η παρούσα μεταπτυχιακή διατριβή επικεντρώνεται στην μελέτη της παράκτιας ζώνης της νήσου Λέρου στο Νοτιοανατολικό Αιγαίο, παρουσιάζοντας τα αποτελέσματα της ερμηνείας των γεωφυσικών στοιχείων που συλλέχθηκαν από το Εργαστήριο Θαλάσσιας Γεωλογίας και Φυσικής Ωκεανογραφίας (Ε.ΘΑ.ΓΕ.Φ.Ω.) τον Ιούνιο του 2011. Η έρευνα φιλοδοξεί να συνεισφέρει στην ανάδειξη της υποθαλάσσιας πολιτιστικής και φυσικής κληρονομιάς του νησιού, καθώς η συλλογή, επεξεργασία και ερμηνεία του συνόλου των δεδομένων επέτρεψε την αναγνώριση και την λεπτομερή χαρτογράφηση υποθαλάσσιων στόχων μεγάλης ιστορικής και περιβαλλοντικής σημασίας. Ως εκ τούτου, η διατριβή κινείται σε δύο κατευθύνσεις. Η πρώτη κατεύθυνση αφορά στον εντοπισμό στόχων πιθανής ιστορικής σπουδαιότητας που εντοπίστηκαν στην επιφάνεια του πυθμένα ενώ η δεύτερη κατεύθυνση αφορά στον εντοπισμό και την αποτύπωση βιογενών σχηματισμών και συγκεκριμένα λειμώνων P. Oceanica και ασβεστιτικών ροδοφυκών (corallegene formations). Οι θαλάσσιες έρευνες πραγματοποιήθηκαν σε δύο διακριτά στάδια, στην συστηματική αποτύπωση του πυθμένα με ηχοβολιστή πλευρικής σάρωσης (EG&G 272 TD) και την οπτική επιβεβαίωση των αποτελεσμάτων της ηχοβολιστικής αποτύπωσης με σύστημα συρόμενης υποβρύχιας κάμερας. Η ανάλυση και επεξεργασία των ηχογραφιών οδήγησε στον εντοπισμό ναυαγίων που συνδέονται με τη Μάχη της Λέρου (9-10/1943), ένα από τα σημαντικότερα πολεμικά γεγονότα που έλαβαν χώρα κατά τη διάρκεια του Δευτέρου Παγκοσμίου πολέμου, στην ανατολική Μεσόγειο και τα οποία αποτελούν πολύτιμα ιστορικά στοιχεία σε παγκόσμια κλίμακα, μεταξύ των οποίων το βυθισμένο ελληνικό αντιτορπιλικό Βασίλισσα ‘Ολγα (D15). Στο πλαίσιο της δεύτερης κατεύθυνσης εντοπίστηκαν και χαρτογραφήθηκαν οι λειμώνες P. Oceanica και οι σχηματισμοί των ασβεστιτικών ροδοφυκών σχεδόν ανά όρμο περιμετρικά της νήσου. Η σχεδίαση των αντιστοίχων υποθαλάσσιων θεματικών χαρτών της παράκτιας ζώνης της Λέρου αναμένεται να αποτελέσουν ένα σημαντικό εργαλείο στην προστασία και στην ανάδειξη της σημαντικής υποθαλάσσιας ιστορικής και φυσικής κληρονομιάς του νησιού / The present study describes the submarine geophysical survey which was carried out in Leros Island, Aegean Sea and presents the results of the geophysical data analysis. The data were collected by the Laboratory of Marine Geology & Physical Oceanography, department of Geology, University of Patras during the period 11-17 June 2011. The research aims to contribute to the enhancement of underwater cultural and natural heritage of the island, as the collection, processing and interpretation of all of the data has allowed the identification of underwater targets of great historic and environmental importance. Geophysical survey in Leros Island, using a side scan sonar (EG&G 272 TD), coupled with ground-truthing by deploying a Towing Camera System of historic shipwrecks from World War II and of the major seabed habitats, namely Posidonia oceanica and coralligène formations. The survey revealed a great number of shipwrecks associated with the Battle of Leros (9-10/1943), one of the most important military events that took place during the World War II, in the Eastern Mediterranean which are considered as valuable historic data on a global scale, including the sunken Greek destroyer Queen Olga (D15). The design of the thematic maps of the coastal zone of Leros is expected to become an important tool in both protecting and promoting the significant underwater cultural and natural heritage of the island.
166

Development potential and financial viability of fish farming in Ghana

Asmah, Ruby January 2008 (has links)
The potential for aquaculture development to make up for an annual 400,000mt shortfall in domestic fish supply was investigated. This involved an overview of the sector to determine its trends and operations and identifying strengths and constraints, a financial viability assessment of the sector, based on mode and levels of operation of existing farms, an assessment of the market and trade for cultured fish with a focus on Oreochromis niloticus, and finally, a GIS approach to update and reassess the potential for aquaculture development in Ghana. Data were obtained from both primary and secondary sources, the former, via fish farmer, dealers and consumer questionnaire surveys. Results of the study showed that interests in fish farming continue to grow with an overall annual average growth rate of 16% since 2000. The existing farms, 1300 in number were however very small with a mean farm size of 0.36ha and a median 0.06ha of which commercial farms accounted for less than 3%. Based on sizes, mode of operation and levels of input and output, five subsistence farm types were identified. Mean production from these pond-based farms ranged from 1436kg/ha/yr- to 4,423kg/ha/yr while that of a medium sized intensive commercial pond farm was 45,999kg/ha/yr. Commercial farming accounted for about 75% of 2006 aquaculture production. The main strength identified was the growing interest in both commercial and non-commercial fish farming and the main constraints were lack of quality seed, low levels of technical support and of knowledge in fish farming practices among non-commercial farmers. Net profits of commercial farms ranged from GH¢ 3,341 (US$3480)/ha/yr to GH¢ 51,444 (US$ 53,587)/ha/yr with payback from 1 to 4yrs, IRR at 35% to 105% and NPV from GH¢ 5,898 to GH¢ 236,412. By contrast, only two of the five non-commercial farm types made positive net returns ranging, from GH¢158 to GH¢1100/ha/yr, with minimum payback period of 14yrs, NPVs of less than 1 and the best IRR being just 4%, when initial capital requirements are full costed. Uncosted family labour inputs and negligible land opportunity costs improved viabilities for two farm types, where net returns/ha/yr increased by more than 50%, minimum payback dropped to 2 years, NPV from GH¢ 4839 to GH¢ 9330 and minimum IRR of 45%. Main constraints identified as affecting the profitability of subsistence farming were the relatively low prices of fish and the low levels of output which could be improved through better farming practices. From the market survey, a huge market potential for tilapia was identified with a current supply deficit of 41,000mt. The most preferred sizes by consumers and with potentially good market price for traders were those weighing at least 200g. For dealers, trading in cultured fish was found to be more profitable than trading wild capture tilapia because of lower wholesaler prices, gross profit margins were GH¢ 0.49/kg and GH¢ 0.25/kg respectively. Preference for tilapia was influenced by taste, availability, and its perceived health benefit. A key constraint to the sector was poor post-harvest handling and preservation of the fish resulting in shorter shelf life. From the GIS study, 2% (3,692 km2) of available land area was identified as very suitable for subsistence and about 0.2% (313.8km2) for commercial farming. A further 97.4% and 84.0% were identified as suitable for subsistence and commercial farming respectively. Areas with potential for cage culture were also identified, which were largely in the southern and mid-sections of the country. The overall conclusions are that based on natural resource requirements, market potential and financial viability, Ghana has the potential to totally make up the shortfall in domestic fish supply through aquaculture production. The current 400,000mt shortfall in domestic fish production can be achieved by 2020 by increasing overall aquaculture production by 60% per annum.
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The state of spatial information for land reform in South Africa : a case study of the Amantungwa Land Reform project.

Kubheka, Sipho. January 2006 (has links)
Many authors and practitioners involved in rural or local development agree that co-operation and the integration of efforts by the delivery agents is crucial for sustainable development programmes. The delivery of Land Reform as initiated by the new government in South Africa (SA) is one programme that has been faced by a number of challenges including the slow pace of delivery, lack of support and co-operation from the key stakeholders, negligible impact on the improvement in the lives of its beneficiaries and many others. Many Land Reform participants including the government argue that among the challenges facing this programme is a lack of co-operation between the key stakeholders including the different spheres of government involved or impacted upon by the delivery of the Land Reform programme. The Department of Land Affairs (DLA) which is responsible for Land Reform delivery is facing challenges in integrating Land Reform with the rural or local level development which is facilitated by the local and district municipalities through the Integrated Development Planning (IDP) process. This thesis seeks to look at how the Land Reform planning process and the internal spatial data systems within the DLA can be used to integrate Land Reform delivery with the municipal IDP processes to attain integrated rural development. There is a growing realization of the fact that the development of an integrated spatial data is critical for sustainable development in SA. A number of initiatives have been embarked upon by various organizations to establish the spatial data infrastructure. However these efforts have been reported to be often fragmented and isolated in the areas of operation and focus. Thus, the challenge is to develop a strategy to develop an integrated spatial data infrastructure that would be used to support sustainable development programmes such as the Land Reform programme. This thesis therefore proposes to look at the various data sources particularly within the DLA and from other organs of state involved in Land Reform and local development with a view to highlight the limitation and shortcomings that can be addressed in integrated spatial data infrastructure. To assess the current status of the spatial data sources and usage for Land Reform implementation, an analysis of the spatial data sources within the DLA was conducted to determine its suitability for the development of an integrated spatial data infrastructure. Different sections of the DLA responsible for acquiring and providing spatial data were assessed to ascertain whether their data can be shared, transferred or integrated to support the Land Reform implementation. An integrated spatial data infrastructure is then proposed as a solution to forge co-operation and collaboration among all users involved in Land Reform implementation. / Thesis (M.Sc.) - University of KwaZulu-Natal, Pietermaritzburg, 2006.
168

Χωρική προσέγγιση της βιολογίας του είδους Falco eleonorae (Aves, Falconiformes) στην Ελλάδα: η περίοδος της αναπαραγωγής, μετανάστευσης και διαχείμασης

Κασσάρα, Χριστίνα 27 June 2012 (has links)
Ο Μαυροπετρίτης (Falco eleonorae Géné, 1839) είναι ένα μεσαίου μεγέθους μεταναστευτικό γεράκι το οποίο επισκέπτεται τη χώρα μας τους καλοκαιρινούς μήνες για να αναπαραχθεί. Οι αναπαραγωγικές αποικίες εντοπίζονται σε νησιά και ακτές της Μεσογείου, της Μακαρονησίας και της βορειοδυτικής Αφρικής, ενώ τους υπόλοιπους μήνες το είδος απαντά στη Μαδαγασκάρη και γειτονικές περιοχές. Στο παρελθόν έχει πραγματοποιηθεί ένας μεγάλος αριθμός μελετών σχετικά με την περίοδο αναπαραγωγής, ενώ για τον υπόλοιπο κύκλο ζωής του είδους οι γνώσεις μας μέχρι τις αρχές του 21ου αιώνα ήταν περιορισμένες. Στην παρούσα διατριβή μελετώνται τα βασικότερα στάδια του κύκλου ζωής του Μαυροπετρίτη, επικεντρώνοντας στην περίοδο αναπαραγωγής, μετανάστευσης και διαχείμασης ατόμων που αναπαράγονται στην Ελλάδα. Συγκεκριμένα, διερευνάται (α) η αναπαραγωγική επιτυχία του είδους και η επίδραση περιβαλλοντικών παραγόντων στην έκβαση της αναπαραγωγικής επιτυχίας, (β) το πρότυπο κατανομής των αναπαραγωγικών αποικιών στο Αιγαίο και Ιόνιο πέλαγος, (γ) τα κριτήρια που χρησιμοποιούν τα αναπαραγωγικά ζευγάρια κατά την επιλογή θέσης φωλιάσματος σε ακατοίκητες νησίδες του Αιγαίου πελάγους, (δ) η περίοδος μετανάστευσης τεσσάρων γερακιών από μια αποικία του Κεντρικού Αιγαίου και οι παράγοντες που επηρεάζουν το πρότυπο μετανάστευσής τους και, (ε) η περίοδος διαχείμασης και το πρότυπο κατανομής των τεσσάρων γερακιών στην περιοχή διαχείμασης. Η εκπόνηση της παρούσας διατριβής βασίσθηκε σε μεγάλο βαθμό στα πρωτογενή δεδομένα που συλλέχθηκαν στο πλαίσιο του προγράμματος «LIFE - ΦΥΣΗ 2003 Δράσεις για την προστασία του Μαυροπετρίτη (Falco eleonorae) στην Ελλάδα (LIFE 03NAT/GR/000091)», με κύριο ανάδοχο την Ελληνική Ορνιθολογική Εταιρεία (Ε.Ο.Ε.) σε συνεργασία με το Μουσείο Φυσικής Ιστορίας Κρήτης (ΜΦΙΚ), το Υπουργείο Αγροτικής Ανάπτυξης και Τροφίμων και τη Βρετανική Ορνιθολογική Εταιρεία (RSPB) και με χρηματοδότηση της Ευρωπαϊκής Επιτροπής και συγχρηματοδότηση του ιδρύματος «Α. Γ.Λεβέντης». Το πρόγραμμα παρακολούθησης της μετανάστευσης των τεσσάρων Μαυροπετριτών πραγματοποιήθηκε στο πλαίσιο του προγράμματος «Μελέτη των πτηνών του ελληνικού θαλάσσιου χώρου» με ανάδοχο την Ελληνική Ορνιθολογική Εταιρεία και με χρηματοδότηση του ιδρύματος «Α. Γ. Λεβέντης». / Eleonora's falcon (Falco eleonorae Géné, 1839) is a medium-sized migratory raptor that visits the Greek islands during the breeding season. Its breeding colonies are distributed on islands and coasts of the Mediterranean Sea, Macaronesia and northwest Africa, while during the rest of the year the species is found in Madagascar and surrounding islets. In previous years most studies focused on the breeding period, while up to the 21st century our knowledge with regards to the rest of its life cycle remained relatively poor. In this thesis i study the main stages of Eleonora's falcon life cycle, focusing on the breeding, migratory and wintering period of individuals that breed in Greece. In particular, i investigate (a) the breeding success of the species and the effect of environmental factors on the outcome of the breeding effort, (b) the distribution pattern of the breeding colonies in the Aegean and Ionean Sea, (c) the criteria the breeding pairs use at the time of nesting site selection in uninhabited islets of the Aegean Sea, (d) the migratory period of four falcons originating from a breeding colony of the Central Aegean Sea and the factors that shape the irmigratory pattern and, (e) the wintering period and the distribution pattern of the four falcons in their wintering grounds. This thesis was based to a great extent on the data collected in the frame of the project "LIFE-Nature 2003 Conservation Measures for Falco eleonorae in Greece (LIFE 03NAT/GR/000091)" undertaken by the Hellenic Ornithological Society (H.O.S.) in collaboration with the Natural History Museum of Crete (NHMC), the Ministry of Rural Development and Food and the Royal Society for the Protection of Birds (RSPB), which was funded by the European Commission and cofunded by the A.G. Leventis Foundation. The migration tracking project was funded by the A.G. Leventis Foundation through project "Survey and Conservation of Seabirds in Greece".
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Site selection for the Small-Scale Aquaculture Farming Systems in the Western Cape : a GIS application

Steer, Lorn Adam 03 1900 (has links)
Thesis (MA (Geography and Environmental Studies))--University of Stellenbosch, 2006. / The Rural Aquaculture Development Programme (RADP) of the Division of Aquaculture at Stellenbosch University (DASU) has the objective of socio-economic development of farm workers and rural communities from previously disadvantaged communities through the provision of opportunities for sustainable economic development by establishing small-scale fish-farming systems on irrigation dams. The Small-Scale Aquaculture Farming Systems (SSAFS) is an initiative of RADP. DASU intends implementing 20 new projects by the end of 2005, 100 by 2010 and at least 200 by 2020. Thus far, sites which can accommodate 25 projects have been identified. The owners of the land on which these 25 possible projects are located are being contacted to gain permission to use the sites for the SSAFS. It is possible that some of the owners of the sites will not allow them to be used so that not all 25 projects will necessarily be implemented. At present the predominant search method employed by DASU to find new sites involves two steps. Initially knowledge is acquired through word of mouth about dams that may be suitable. Personnel then drive to these dams for further inspection, to see if they are indeed suitable. This method of search is clearly both expensive and time-consuming. Geographical information systems (GIS) have as yet not been considered as an alternative and/or supplementary site selection method for the SSAFS. GIS tools and principles can reduce both expenses and time in locating sites by reducing the number of dams to be visited to only those that are optimal (i.e. they present the least risk of the SSAFS projects failing). A new site selection methodology using GIS was developed which is faster and less expensive than existing site selection methods. The GIS site selection methodology revolves around the isolation and selection of dams in the Berg and Breede River water management areas, based on their ability to fulfil certain parameters of critical variables comprising dam dimensions, environmental issues, distance measures and site security, according to a priority hierarchy, that determine a successful site for trout farming according to methods employed by the SSAFS. Once this methodology was produced, it was presented to five people who are directly involved with the SSAFS as well as four others who are not involved with the SSAFS but who might find the methodology useful, to determine whether they hold that the methodology is indeed better than existing search methodologies. Those who were presented the GIS site selection methodology felt that it is very useful and that it could be employed in future to make more informed choices when locating new sites for the SSAFS as well as other aquacultural enterprises.
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Participatory mapping and the use of GIS for sustainable land use planning in the Hardap Region, Namibia

Mundia, Lisho Christoh 08 1900 (has links)
Namibia, like most developing countries, lacks complete and comprehensive sustainable land use plans. This has a negative impact on a range of land use activities. Although Geographical Information System (GIS) is used as a planning tool in Namibia in an ad hoc manner, there is no broader comprehensive framework to guide applications of GIS as a planning tool specifically for land use planning (LUP). The purpose of this study is to demonstrate how integration of participatory mapping and GIS can be used to enhance land use planning in the Hardap Region, Namibia. The study seeks to point out lack of local communities’ engagement in LUP process; lack of policy frameworks and guidelines for Integrated Land Use Planning (ILUP); and poor data management. The study adapted quantitative and qualitative approaches to collect relevant data and information related to LUP. Data collected using participatory approaches such as Focus Group Discussion (FGD), Participatory Rural Appraisal (PRA) and Strengths Weaknesses Opportunities and Threats (SWOT) analysis were applied in an integrated manner in various contexts. FGDs were used to evaluate participants’ knowledge of LUP in the Hardap region. Besides participating in the FGDs, PRA and SWOT analysis, the participants also expressed opinions concerning desirable and undesired land uses in the region. Sketch and photo- mapping methods were found to be suitable approaches to capture local knowledge. GIS was found to be effective in integrating participatory maps produced by the local communities and existing spatial land use data. The results shows that local communities are eager to learn about participatory approaches and are willing to share their views and knowledge on land use in their respective areas. A user-friendly comprehensive georeferenced digital database was created for the Hardap region. This database is used for spatial data management, analyses, maintenance and production of maps. Maps of new development initiatives in the region were produced. The frameworks and guidelines suggested in this study has the potential to guide participatory techniques aided by GIS technology involving local communities in sustainable LUP processes in Namibia. The digital database incorporates experts’ knowledge on the users and implementation aspects, making it a LUP benchmark tool of Namibia. Key recommendations include incorporation of GIS technology in the ILUP, implementation of comprehensive participatory LUP, adoption of guidelines for future LUP, skills training and capacity development, and result-based monitoring. / Geography / D. Litt. et Phil. (Geography)

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