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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.
91

[en] A MAP-BASED INTERFACE EVALUATION METHOD / [pt] UM MÉTODO DE AVALIAÇÃO PARA INTERFACES BASEADAS EM MAPAS

MARIA LUCIA ARRAES SEIXAS 20 December 2004 (has links)
[pt] A integração de informação geográfica e mapas digitais nos Sistemas de Informação Geográfica (SIGs) produz soluções para vários grupos de usuários. Vem crescendo o número de usuários não especializados que utilizam SIGs na Web ou em desktop para localizar endereços, planejar rotas, planejar viagens, encontrar lugares, e assim por diante. Estas aplicações menos complexas e destinadas a qualquer pessoa carecem fundamentalmente de avaliação, pois da qualidade da interação depende seu sucesso comercial. Apesar desta necessidade, praticamente não encontramos pesquisas sobre como avaliar estas aplicações mais simples de SIGs. Neste trabalho propomos um método de Inspeção Semiótica para Interfaces baseadas em Mapas (o ISIM) capaz de analisar o efeito de representações usadas nestas interfaces na comunicação da informação geográfica. O ISIM combina técnicas analíticas e empíricas. As técnicas analíticas são usadas para definir contextos de uso e perfis de usuários, bem como para interpretar observações empíricas. Técnicas empíricas são usadas em testes e entrevistas com usuários, para comparar parte dos dados obtidos com as técnicas analíticas. O ISIM, que inicialmente abrange dos SIGs apenas as interações baseadas em mapas, identifica uma classe de problemas básicos deste tipo de interação e, como é o caso de vários outros métodos semióticos, dá indicações sobre possibilidades de solução para eles. / [en] The integration of digital maps and geographical information into Geographical Information Systems (GIS) produces solutions for several groups of users. There is an increasing number of non experts that use GIS on the Web or in desktop applications to locate addresses, plan routes and trips, find places, and so on. Less complex applications designed for general use critically need evaluation, because their commercial success depends heavily on the quality of human-computer interaction. In spite of such critical need, it is very hard to find research about how to evaluate these kinds of simpler applications. We propose a semiotic inspection method (whose acronym in Portuguese is ISIM) that analyzes the effect of representations in map-based interfaces to communicate geographic information. ISIM combines analytic and empirical techniques to carry out evaluations. Analytic techniques are used to define contexts of use and users' profiles, as well as to interpret empirical observations. ISIM also uses an empirical technique of tests and interviews with users. ISIM, whose scope encompasses only GIS map-based interaction, can identify a class of basic problems of interaction and, as is the case with many semiotic methods, hint at design solutions for them.
92

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>
93

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>
94

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.
95

Karst Hydrogeology of the Haney Limestone, South-Central Kentucky

Arpin, Sarah Marie 01 May 2013 (has links)
South-central Kentucky has one of the world’s most intensively studied karstareas, with most work focusing on the Mammoth Cave System and related caves and aquifers. However, slightly higher in the stratigraphic section than Mammoth Cave, the Haney Limestone is a locally important but less well studied carbonate aquifer. This research provides the most comprehensive synthesis to date of the karst hydrogeology of the Haney Limestone of south-central Kentucky, focusing on the distribution and controls on cave and karst features developed within. In contrast to drainage systems within the major limestones below, joints are the most dominant control on passage development in the Haney Limestone within the study area and the orientation of these joints is consistent with that of regional joint sets. Bedding planes and the presence of insoluble rock at the base of the Haney also exert control on conduit development in the Haney Limestone. Most of the caves of the study area developed in the Haney Limestone are singleconduit caves that receive water through direct, allogenic sources. Cave entrances are frequently perennial spring resurgences and the presence of active streams suggests that the caves function within the contemporary landscape, acting as drains for localized recharge areas. The hydrology of the Haney Limestone plays an important, if localized, role in the regional hydrology of south-central Kentucky, integrated into the current system of surface and subsurface drainage of the regional karst landscape. Evidence supports the idea that caves of the Haney Limestone are, geologically, relatively recent phenomena. A majority of the cave passages in the study area are hydrologically active, the water resurging from the sampled springs is typically undersaturated with respect to limestone, and the caves in some case appear to be developed along potential stress release fractures associated with small, apparently young valleys. This suggests that caves in the Haney Limestone were not directly influenced by the incision of the Green River over vast periods, like Mammoth Cave, but that cave development is a largely contemporary process.
96

Environmental Health and Safety data integration using Geographical Information Systems

George, David Paul January 2008 (has links)
Environmental Health and Safety (EHS) departments in many organizations are faced with two interrelated problems which limit their ability to make accurate decisions based on quality data. First, many EHS departments follow a reactive business management model and need to work towards a proactive continuous improvement model to better manage EHS. The second is a lack of data integration and interoperability between the numerous different EHS data sources and systems. EHS departments are challenged with managing large quantities of data generated through tracking and monitoring programs to continuously improve EHS performance. EHS data can be in many forms paper, digital files, spreadsheets, images, relational databases and proprietary software applications. EHS data have strong spatial relationships, which makes the use of Geographical Information Systems (GIS) a very cost effective and feasible solution for integrating and managing EHS data. This thesis will outline how GIS brings to EHS the advantages of traditional IT methods with the added benefit of spatial analytical operations such as map overlay, relationships and querying, and informative visual presentation through maps, floor plans, and imagery through the implementation of a GIS database for EHS called GeoSpatial Environmental Health and Safety (GEO-EHS).
97

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.
98

Environmental Health and Safety data integration using Geographical Information Systems

George, David Paul January 2008 (has links)
Environmental Health and Safety (EHS) departments in many organizations are faced with two interrelated problems which limit their ability to make accurate decisions based on quality data. First, many EHS departments follow a reactive business management model and need to work towards a proactive continuous improvement model to better manage EHS. The second is a lack of data integration and interoperability between the numerous different EHS data sources and systems. EHS departments are challenged with managing large quantities of data generated through tracking and monitoring programs to continuously improve EHS performance. EHS data can be in many forms paper, digital files, spreadsheets, images, relational databases and proprietary software applications. EHS data have strong spatial relationships, which makes the use of Geographical Information Systems (GIS) a very cost effective and feasible solution for integrating and managing EHS data. This thesis will outline how GIS brings to EHS the advantages of traditional IT methods with the added benefit of spatial analytical operations such as map overlay, relationships and querying, and informative visual presentation through maps, floor plans, and imagery through the implementation of a GIS database for EHS called GeoSpatial Environmental Health and Safety (GEO-EHS).
99

An Approach To Investigate Relationship Between Speed And Safety On Urban Arterials

Ardic Eminaga, Zerrin 01 February 2008 (has links) (PDF)
Traffic safety is an important problem in today&rsquo / s world with increasing number of fatalities and injuries in traffic accidents. For the solution of this problem, determination of accident prone locations on a network and reasons behind is an essential step, which is studied to some extend via different traffic accident analyses in the literature. While major factors affecting accident risk, such as speed, congestion, infrastructural aspects are known, it is still very difficult to figure out the interaction among these factors, due to complexity in the spatial and temporal distribution of the aforementioned factors and traffic network characteristics. While the case of accident analysis on highways is simpler, in case of urban roads, it requires more effort due to more complex traffic networks with quite a number of conflict points and varying flow characteristics. To investigate possible relationships between speed and accident occurrence on urban arterials, a Geographic Information Systems based accident analysis methodology (GIS-TAAM) is developed in this study. This methodology uses time-dependent average link speeds (calculated from GPS-based data) and accident history of links, and three safety measures in thematic accident maps: i) total number of accident, ii) a severity index based on number of fatality and injury accidents, and iii) an alternative severity index based on total number of fatalities and injuries. The implementation of the proposed methodology and its deliverables are discussed over a pilot study on in&ouml / n&uuml / Boulevard &ndash / EskiSehir Road, Ankara.
100

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.

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