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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.
11

Μοντέλο διαστασιοποίησης δικτύου κορμού ευρυζωνικών δικτύων βασιζόμενο στην εφαρμογή

Φράγκος, Γεώργιος 25 June 2009 (has links)
Στο πρώτο κεφάλαιο αναπτύσσονται οι έννοιες Γεωδαισία, Γεωδαιτικό ή τοπογραφικό δίκτυο, τα είδη των δικτύων, τα προβολικά συστήματα, τα διεθνή και τα ελληνικά γεωδαιτικά συστήματα αναφοράς καθώς και η μεταξύ τους μαθηματική σχέση. Στο δεύτερο κεφάλαιο αναφέρονται ο ορισμός και τα είδη του Γεωγραφικού Συστήματος Πληροφοριών, τα δομικά του στοιχεία, η οργάνωσή του, οι εφαρμογές και δυνατότητές του. Επίσης ιδιαίτερη έμφαση δίνεται στη διασύνδεση του Γ.Σ.Π με την ευρυζωνικότητα, γεγονός το οποίο αναδεικνύει την σημαντικότητα ύπαρξης των GIS(Γ.Σ.Π). Στο τρίτο κεφάλαιο αναλύεται το πρόγραμμα που χρησιμοποιήθηκε στην υλοποίηση, δηλαδή το Quantum GIS, ενώ ακολουθούν οι ψηφιακοί χάρτες καθώς και οι αναλυτικές αναφορές σχεδιασμού τους, οι οποίοι κατασκευάστηκαν με χρήση του QGIS. Η παραπάνω ανάλυση αναφέρεται στους δήμους Πύργου, Αμαλιάδος, Πάτρας, Ρίου, Αιγίου, Αγρινίου, Ναυπλίου και Μεσολογγίου. Στο τέταρτο κεφάλαιο αναπτύσσονται δύο αλγόριθμοι εφαρμογής: ένας για την ανίχνευση του περικλειόμενου τριγώνου(με κορυφές ασύρματα κέντρα) δοθέντος συγκεκριμένου σημείου και ένας για την εύρεση της διαδρομής από δοθέν σημείο έως τον πλησιέστερο κόμβο ενός δικτύου οπτικών ινών. Στο πέμπτο κεφάλαιο παρουσιάζονται τα συμπεράσματα της διπλωματικής εργασίας και ακολουθεί η βιβλιογραφία που χρησιμοποιήθηκε. / -
12

Deccan Queen: A Spatial Analysis of Poona in the Nineteenth and Early Twentieth Centuries

Mullen, Wayne Thomas January 2003 (has links)
This thesis is structured around the analysis of a model that describes the Cantonment, the Civil Lines, the Sadr Bazar and part of the Native City of the Western Indian settlement of Poona in the late nineteenth and early twentieth centuries.
13

GIS Based Study of Probable Causes of Increase in Cancer Incidences in Iraq After Gulf War 1991

Muhammad, Hassan January 2006 (has links)
<p>The use of banned toxic weapons in Iraq during Gulf War 1991 started new debates. The increase in cancer cases was the main focus of these issues. The gap in literature motivated this study to find out the correlation between use of DU weapons and its effects on human health. The different probable causes of increase in cancer cases, in Iraq after Gulf War 1991, have been discussed in this study. Three causes; DU, brick kilns smoke near Basra and Kuwait oil fire smoke have been selected. The major emphasis of this study is on use of Depleted Uranium (DU). Different statistical data sets have been used and displayed in the form of maps and graphs using GIS methodologies. It’s hard to say after this GIS based study that the fired Depleted Uranium is the sole cause of increase in cancer incidences in Iraq, while some trends and risk factors at least can be observed where increase in cancer cases in different Governorates in Iraq is clearly visible after Gulf War 1991. After analyzing satellite images of different dates, the second part of this study concludes that Kuwait oil wells smoke is not responsible for increase in cancer incidences in Iraq. A small debate has been initiated regarding smoke in brick kilns near Basra. No study has been found in this regard which can provide evidences that brick kilns smoke is the cause of increase in cancer incidences in southern Iraq.</p><p>It’s not easy to carry out a full fledge GIS based study to prove DU as cause of increase in cancer cases. The main limitation in this regard is unavailability of required data. Therefore a new GIS based methodology has been devised which can be used to prove relationship between exposure to DU and increase in cancer cases in Iraq. This new methodology is also dependent on specific data sets. Hence this methodology also recommends the collection of specific data sets required for this study.</p><p>At the end, a detailed study, with honesty, has been suggested to fill up the gaps found in literature whether use of Depleted Uranium in weapons is harmful for human health or not.</p>
14

Pixgis : An Application for Map-centric Management of Photographs with Embedded Spatial Metadata

Sjödin, Erik January 2006 (has links)
<p>This thesis presents Pixgis; a novel application for map-centric management of photographs. In short Pixgis is an interactive environment in which photographs may be discovered, viewed and managed through maps. With Pixgis finding photographs from a specific location or of a particular structure is as easy as finding the location or structure on a map. As Pixgis simultaneously displays maps, photographs and spatial metadata it also enables users to analyze photographs in new manners. This thesis work illustrates the benefits of applications for map-centric management of photographs, exposes the problems one faces when implementing such applications and presents novel solutions to many of these problems. The thesis also elaborates on spatial metadata and methods for acquisition of photographs with embedded spatial metadata.</p>
15

Malignancies in Sweden after the Chernobyl accident in 1986

Tondel, Martin January 2007 (has links)
On 26 April 1986 an accident occurred in the Chernobyl nuclear power plant resulting in the release of large amount of radionuclides. Almost five percent of the total released caesium-137 was deposited in Sweden. The incidence of malignancies in the most affected counties in Sweden was investigated in three epidemiological studies. In the first study the incidence of malignancies in children and adolescents was studied for the period 1978-1992. The parishes and their inhabitants were classified according to the ground deposition of caesium-137 on an analogue map provided be the Swedish Radiological Protection Authority. A continuous increase of brain tumour incidence observed during the time of the study had no clear relationship to the Chernobyl fallout. A somewhat decreased relative risk of ALL was observed in areas with increased deposition. Other malignancies showed no changes in incidence over time or with regard to the exposure of caesium-137. In study II and III we enlarged the study base by including adults. We improved the methodology by defining a cohort of subjects who lived in the same parish from 31 December 1985 to 31 December 1987. The inhabitants from seven counties were included. Parishes were classified the same way as in study I. Due to the large number of individuals six exposure categories could be created; &lt;3, 3–29, 30–39, 40–59, 60–79, and 80–120 kBq caesium-137/m2. The inhabitants of the 117 non-affected parishes (&lt;3 kBq/m2) served as reference. During the 1988-1996 followup, 22,409 malignancies were recorded. The MH-IRR in the fully adjusted model was 1.00 (reference), 1.05, 1.03, 1.08, 1.10 and 1.21, respectively. ERR was 0.11 per 100 kBq/m2 (95% CL 0.03;0.20). A more advanced method was used in Study III by ignoring the exposure classification for parishes, and instead matching the dwelling coordinate to a digital map of deposition of casesium-137. In spite of a more valid exposure classification the risk estimates were similar in study II and III. Also, the ERR during the longer follow-up of 1988-1999 was almost identical, 0.10 per 100 kBq/m2 (95% CL 0.00;0.23). The strongest dose-response relationship was seen in the first four years (1988-1991). No obvious excess for leukaemia or thyroid cancer was recognised in either study II or III. The estimated number of exposure related cases was calculated to 849 in study II and 1,278 in study III. Our interpretation is that we have shown an increased incidence of total malignancies with dose-response relationship for caesium-137, only a few years after the Chernobyl accident. In study IV we compared the two different ways of classifying the exposure in study II and III. Out of the 450 parishes 111 got a different classification. The similar risk estimates in study II and III could probably be explained by relatively homogenous exposure in the parishes making the intra-parish difference less influential, especially when included in categories. In study V we examined the urinary excretion of 8-OHdG in Belarussian children from areas with high and low fallout of caesium-137, respectively. We found significantly lower urinary 8-OHdG levels in children from rural contaminated areas compared to urban uncontaminated areas, suggesting an urban, rather than a radiation related, risk factor. Using the Hill criteria for causality there is support for a causal inference between the fallout of caesium-137 from the Chernobyl accident and the increased incidence in total malignancies in Northern Sweden.
16

Pixgis : An Application for Map-centric Management of Photographs with Embedded Spatial Metadata

Sjödin, Erik January 2006 (has links)
This thesis presents Pixgis; a novel application for map-centric management of photographs. In short Pixgis is an interactive environment in which photographs may be discovered, viewed and managed through maps. With Pixgis finding photographs from a specific location or of a particular structure is as easy as finding the location or structure on a map. As Pixgis simultaneously displays maps, photographs and spatial metadata it also enables users to analyze photographs in new manners. This thesis work illustrates the benefits of applications for map-centric management of photographs, exposes the problems one faces when implementing such applications and presents novel solutions to many of these problems. The thesis also elaborates on spatial metadata and methods for acquisition of photographs with embedded spatial metadata.
17

Developing A Geotechnical Microzonation Model For Yenisehir (bursa) Settlement Area

Kolat, Cagil 01 June 2010 (has links) (PDF)
The purpose of this study is to develop a geotechnical microzonation model regarding the suitability of the residential areas in Yenisehir (Bursa, Turkey), which is a currently developing settlement area in a seismically active region. For this purpose, soil properties and dynamic soil behaviors of the study area were assessed. Soil classification, soil amplification, natural soil predominant period, resonance phenomena and liquefaction potential of the study area were evaluated using borehole data and microtremor measurements. The raw data obtained from the previous studies carried out at Yenisehir were used for these assessments. The liquefaction potential for the study area was evaluated both in two-dimensional planimetric and three-dimensional volumetric assessments. Two geotechnical microzonation maps were produced for the study area according to the surface damage due to liquefaction (according to two different methods), soil amplification and distance to streams maps / by using Geographical Information Systems (GIS) based Multi-Criteria Decision Analysis. The weight values were assigned to the layers using Analytical Hierarchical Process method by pairwise comparisons. Evaluating geotechnical microzonation maps produced, the safest areas were found on the northern sites of the study area. The most critical areas were found to be in the middle and the southeast parts of the study area.
18

An Attempt To Classify Turkish District Data: K-means And Self-organizing Map (som) Algorithms

Aksoy, Ece 01 January 2005 (has links) (PDF)
ABSTRACT AN ATTEMPT TO CLASSIFY TURKISH DISTRICT DATA: K-MEANS AND SELF-ORGANIZING MAP (SOM) ALGORITHMS Aksoy, Ece M.S., Department of Geodetic and Geographic Information Systems Supervisor: Assoc. Prof. Dr. Oguz ISik December 2004, 112 pages There is no universally applicable clustering technique in discovering the variety of structures display in data sets. Also, a single algorithm or approach is not adequate to solve every clustering problem. There are many methods available, the criteria used differ and hence different classifications may be obtained for the same data. While larger and larger amounts of data are collected and stored in databases, there is increasing the need for efficient and effective analysis methods. Grouping or classification of measurements is the key element in these data analysis procedures. There are lots of non-spatial clustering techniques in various areas. However, spatial clustering techniques and software are not so common. This thesis is an attempt to classify Turkish district data with the help of two clustering algorithms: K-means clustering and self organizing maps (SOM). With the help of these two common techniques it is expected that a clustering can be reached, which can be used for different aims such as regional politics, constructing statistical integrity or analyzing distribution of funds, for same data in GIS environment and putting forward the facilitative usage of GIS in regional and statistical studies. All districts of Turkey, which is 923 units, were chosen as an application area in this thesis. Some limitations such as population were specified for clustering of Turkey&rsquo / s districts. Firstly, different clustering techniques for spatial classification were researched. K-Means and SOM algorithms were chosen to compare different methods with Turkey&rsquo / s district data. Afterward, database of Turkey&rsquo / s statistical datum was formed and analyzed joining with geographical data in the GIS environment. Different clustering software, ArcGIS, CrimeStat and Matlab, were applied according to conclusion of clustering techniques research. Self Organizing Maps (SOM) algorithm, which is the best and most common spatial clustering algorithm in recent years, and CrimeStat K-Means clustering were used in this thesis as clustering methods.
19

Near-optimum cost minimisation of transporting bioenergy carriers from source to intermediate distributors

Roberts, Theari 03 1900 (has links)
Thesis (MScEng (Industrial Engineering))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: The world is facing an energy crisis with worldwide energy consumption rising at an alarming rate. The effects that fossil fuels have on the environment are also causing concern. For these two reasons the world is determined to find ‘cleaner’, renewable and sustainable energy sources. The Cape Winelands District Munisipality (CWDM) area has been identified as the study area for a bioenergy project. The CWDM project aims to determine the possibility of producing bioenergy from lignocellulosic biomass, and transporting it as economically as possible to a number of electricity plants within the study area. From the CWDM project a number of research topics were identified. The aim of this thesis is to determine the best location for one or more processing plants that will maximise the potential profit through the entire system. This is achieved by minimising the overall life cycle cost of the project. It takes into account costs from establishing and maintaining the crops, harvesting, transportation, conversion and generation; with a strong focus on the transport costs. In conjunction with a Geographical Information Systems (GIS) specialist and taking into account various factors such as electricity demand, heat sales and substation locations, 14 possible plant locations were identified. The possible supply points for each of the 14 plant locations were then analysed by GIS again to yield data in terms of elevation, road distances and slope. The transport costs were calculated using the Vehicle Cost Schedule (VCS) from the Road Freight Association (RFA) and fuel consumption calculations. It takes into account slope, laden and unladen transport and considers different transport commodities. These calculations together with the other associated costs of the life cycle are then combined with the results of the GIS into an EXCEL file. From this a transportation optimisation model is developed and the equivalent yearly life cycle cost of each of the 14 demand points are minimised by means of LINGO software. Initially runs were done for 2.5 MW capacity plants. From the high profit areas identified here, a single area was chosen and further runs were done on it. These runs were performed to determine the effect of different plant capacities on the life cycle costs, as well as how it affects the farm gate price that can be paid to the farmer. It also determined the effect of farmer participation at different plant capacities. The results indicate that it is currently possible to pay a farmer between R 300.00 and R 358.00 for a ton of biomass. It also revealed that with higher participation from farmers in the CWDM project, lower costs and higher farm gate prices will result, since the transport costs will be lower. Although all the costs within the life cycle are variable over time, the transport cost is the only cost that varies spatially and this will have a major effect on the overall system cost. The thesis found that generating electricity from woody biomass is feasible for all areas that were considered as well as for all variations considered during the sensitivity analysis. For the recommended plant size of 5 MW the transport of logs will be optimum. / AFRIKAANSE OPSOMMING: Die tempo waarteen energieverbruik wêreldwyd styg is ʼn rede tot kommer. Die nadelige effek wat fossiel brandstowwe op die omgewing het, is ook ʼn probleem. Hierdie twee redes is hoofsaaklik wat die wêreld dryf om ‘skoner’ hernieubare en volhoubare energie bronne te vind. Die Kaapse Wynland Distrik Munisipaliteit (KWDM) area is identifiseer as ʼn studie area vir ʼn bio-energie projek. Die doel van die KWDM projek is om die vervaardiging van bio-energie vanaf plantasies, die vervoer van hierdie bome sowel as die prosessering koste by die fabriek te bepaal en te evalueer. Vanuit die KWDM projek het `n aantal tesisse ontwikkel waarvan hierdie een is. Die doel van hierdie tesis is om die beste posisie vir een of meer prosesserings fabrieke te bepaal wat die potensiële wins van die KWDM projek sal maksimeer. Dit is ook gemik daarop om die ekwivalente jaarlikse oorhoofse lewenssiklus koste van die projek te minimeer. Dit neem die vestiging en onderhoud van gewasse, oeskostes, vervoerkostes en proseskostes in ag, met ʼn spesifiek fokus op die vervoerkoste. In samewerking met `ʼn “Geographical Information Systems” (GIS) spesialis en deur verskeie faktore, soos elektrisiteitsverbruik, inkomste vanaf hitte verkope en substasie posisies, in ag te neem is 14 moontlike fabriek posisies identifiseer. Verder is die moontlike voorsienings areas van elk van die 14 fabriek posisies weer deur GIS analiseer om resultate in terme van hoogte bo seespieël, padafstand en helling te verkry. Die vervoerkostes is verkry vanaf die “Vehicle Cost Schedule” (VCS) van die “Road Freight Association” (RFA), asook berekeninge wat die brandstof verbruik in ag neem. Hierdie kostes sluit in die effek van gradiënt, gelaaide en ongelaaide vervoer sowel as verskillende vervoer produkte. Hierdie berekeninge sowel as die ander kostes in die siklus en die resultate van GIS is kombineer in ʼn EXCEL leer. Hierdie data word dan gebruik om ʼn LINGO model te ontwikkel en die oorhoofse lewenssiklus koste van elk van die 14 fabriek posisies te minimeer. Optimering is gedoen vir 2.5 MW kapasiteit fabrieke. Uit die beste areas is een area identifiseer en verdere lopies is daarop gedoen. Die doel van hierdie lopies is om die effek van verskillende fabriekskapasiteit op die lewensiklus koste te bepaal, asook die effek daarvan op die prys wat aan die boer betaal word vir hout. Hierdie lopies is ook gebruik om die effek van boer deelname te bepaal. Die resultaat dui aan dat dit tans moontlik is om ʼn boer tussen R 300.00 en R 358.00 te betaal vir ʼn ton biomassa. Dit het ook gewys dat hoe meer boere deelneem aan hierdie projek hoe laer is die oorhoofse lewensiklus koste en hoe hoër is die prys wat betaal kan word vir hout aangesien die vervoerkoste laer sal wees. Alhoewel al die lewensiklus kostes veranderlik is oor tyd, is dit net die vervoerkoste wat ʼn ruimtelike komponent ook het en dit sal ʼn groot effek op die oorhoofse lewenssiklus koste hê. Die tesis bevind dat dit lewensvatbaar is vir alle areas in die studie om elektrisiteit op te wek vanaf hout biomassa, selfs al word die uiterse variasie in die sensitiwiteitsanalise gebruik. Vir die aanbeveling van ʼn 5 MW fabriek sal die goedkoopste vervoer opsie boomstompe wees.
20

Geoprocessamento aplicado na distribuição espacial da capacidade do uso na microbacia do Córrego dos Rochas, Avaré (SP)

Galatti Filho, Francisco Antônio [UNESP] 22 August 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:26:46Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-08-22Bitstream added on 2014-06-13T20:15:41Z : No. of bitstreams: 1 galattifilho_fa_me_botfca.pdf: 786923 bytes, checksum: 136cd939700e544ad54c137640d7f4fb (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Universidade Estadual Paulista (UNESP) / O objetivo, deste trabalho foi a espacialização da capacidade de uso das terras da microbacia do Córrego dos Rochas, Município de Avaré-SP, obtida através da utilização do Sistema de Informação Geográfica - Idrisi, visando contribuir para uma melhor organização territorial e planejamento de uma adequado da ocupação do solo. Os resultados obtidos a partir da metodologia utilizada permitiram mostrar que a maior parte das áreas de terras da microbacia dos Rochas são formadas por solos pertencentes às unidades: LATOSSOLOS VERMELHO-AMARELOS (LVA52) Distróficos (36,64%) e LATOSSOLO VERMELHOS (LV4) Eutroférricos e Distroférricos (30,30%), apresentando textura arenosa. Quanto à declividade, houve um predomínio de áreas com classes de declive de 0-12%, relevo plano a ondulado (61,37%) da área da microbacia, mostrando que essas terras são propícias para o cultivo de culturas anuais, com amplo uso da mecanização. A maior parte das terras foi classificada como sendo da classe IV (73,79 %) de capacidade de uso, porém, foram encontradas as seguintes subclasses de capacidade de uso das terras: IIe,s; IIIe; IVs; IVe; IVe,s, VIe e VIIe. As subclasses de capacidade IVe; IVe,s, IVs e VIe foram as mais representativas, mostrando tratar-se de terras que podem ser utilizadas para fins agrícolas, próprias para lavouras em geral, ressaltando-se que, quando cultivadas sem cuidados 2 especiais, ficam sujeitas a severos riscos de depauperamento, principalmente quando os solos são utilizadas culturas anuais. O Sistema de Informação Geográfica - Idrisi mostrou-se eficiente na determinação da capacidade de uso das terras da microbacia do Bairro dos Rochas, Município de Avaré-SP, demonstrando que a utilização de ferramentas de geoprocessamento facilita e agiliza os trabalhos dos cruzamento de dados, permitindo o armazenamento digital... . / In this context, the present work had a purpose the determination of the shart of land use capacity of the watershed of the Rochas in Municipal District of Avaré-SP, obtained through the use of Geographical Information System - Idrisi, looking for contribute to a better territorial organization and for the planning of a right occupation of the soil. The results obtained with the used methodology to show that the most of the areas of the watershed of the Rocha are organized by soil belonging to the units LVA52d (36, 54%) and LV4e (30, 30%) presenting textures that are sandy. About the declivity, had a predominance of areas with slope classes of 0-12%, plane relief to wavy (61, 37%) of the watershed showing that this lands are good to cultivate the annual cultures, with wide use of the mechanization. The biggest part of the lands of watershed were classified as being of the class IV of use capacity, but were found the following subclasses of capacity of land uses: IIe,s; IIIe; IVs; IVe; IVe,s, VIe e VIIe. The capacity subclasses IVe; IVe,s, e IVs (73,79%) e VIe (15,56%) were the most representatives, showing been about lands that can be used to agricultural ends, private to farming majority, jutting out that when cultivated without special cares, they stay in dangerous risks of impoverishment, mainly when the soils are cultivated with annual cultures. Information Geographical System - Idrisi show itself efficient in the determination of capacity in land uses of the wastershed of the Rochas in the Avaré-SP Municipal District, showing that the use of geoprocessing tools digital storage that will come to be used to another analyses, above all to future planning of the territories and environment areas studied already.

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