No description available.

No description available.

No description available.

No description available.

Considerable interest remains in capturing once geographical information at the fine scale, and from this, automatically deriving information at various levels of detail and scale via the process of map generalisation. This research aims to develop a methodology for transformation of geographic phenomena at a high level of detail directly into geographic phenomena at higher levels of abstraction. Intuitive and meaningful interpretation of geographical phenomena requires their representation at multiple levels of detail. This is due to the scale dependent nature of their properties. Prior to the cartographic portrayal of that information, model generalisation is required in order to derive higher order phenomena typically associated with the smaller scales. This research presents a model generalisation approach able to support the derivation of phenomena typically present at 1:250,000 scale mapping, directly from a large scale topographic database (1:1250/1:2500/1:10,000). Such a transformation involves creation of higher order or composite objects, such as settlement, forest, hills and ranges, from lower order or component objects, such as buildings, trees, streets, and vegetation, in the source database. In order to perform this transformation it is important to model the meaning and relationships among source database objects rather than to consider the object in terms of their geometric primitives (points, lines and polygons). This research focuses on two types of relationships: taxonomic and partonomic. These relationships provide different but complimentary strategies for transformation of source database objects into required target database objects. The proposed methodology highlights the importance of partonomic relations for transformation of spatial databases over large changes in levels of detail. The proposed approach involves identification of these relationships and then utilising these relationships to create higher order objects. The utility of the results obtained, via the implementation of the proposed methodology, is demonstrated using spatial analysis techniques and the creation of ‘links’ between objects at different representations needed for multiple representation databases. The output database can then act as input to cartographic generalisation in order to create maps (digital or paper). The results are evaluated using manually generalised datasets.

Traditional evaluations of habitat quality fail in their spatial incompleteness, their lack of contextual information and their poor consideration of urban environments. These issues are addressed here through the derivation and application of an urban-specific multi-criteria Habitat Value Index (HVI), providing relevant data in a straightforward, rapid and replicable manner. Both the current distribution and projected changes in landscape HVI are shown using the IDRISI Geographical Information System, providing quantitative information to land-management decision-makers. Using an urban-specific habitat classification in combination with aerial photographic interpretation habitat patches were identified in study areas in the West and South of Wolverhampton. The classification and location of the habitat patches were fieldchecked then each patch was evaluated using four criteria: structural elements, indicator species, general habitat structure and aesthetics. Using a tick-list approach the total number of structural elements and indicator species from pre-determined lists was noted in the field. General habitat structure and aesthetics were also evaluated in the field with each patch assigned to a single category for each. The criteria details for each patch were then transferred onto a GIS and for each criterion a map was generated showing its spatial distribution over the study area. The structural elements and indicator species totals were converted to scores based on scoreclasses, while the categories for general structure, aesthetics and the specific habitat type classification were used as weights by determining each to be either quality (weight = 2) or non-quality (weight = 1). For each habitat patch the structural elements and indicator species scores were then combined with the total weights to produce an HVI. All the habitat patch values for the study area were displayed in map form to give a contextual view of the distribution of ecological 'value' within the area. An additional, simple measure was also devised for measuring the status and quality of connectivity and contiguity within the study area. Sample criteria totals were then used predictively to quantitatively demonstrate the effects of landscape alteration on both the spatial distribution of the HVI and the connectivity and contiguity measures.

Kαταγραφή και Επεξεργασία για το Δήμο Νηλέως των τοπογραφικών, γεωλογικών και πληθυσμιακών χαρακτηριστικών με τη χρήση των Γ.Σ.Π. / The analyse of the topographical and geological characteristics and also elements about the popularity of area Nileos with the use of G.I.S.

This thesis has two main aims. First, to establish whether the strengthening in 1988 of the right of parents to choose a secondary school for their child has led to increased travel to out-of-catchment schools in a case study area. Second, to identify the extent of socio-spatial variation of patterns and trends in choice of school. Secondary school transfer data relating to over 16,000 children for 1991 and 1993 to 1995 was analysed in a Geographical Information System (GIS). One hundred and sixty two parents of children about to transfer to secondary school were interviewed with the objective of revealing the contextual factors underlying the patterns and trends of pupil movements identified in the course of the GIS analysis. The practice and outcomes of parental choice were examined at four scales: the parent, the neighbourhood, the school and the LEA Area. Whilst the main value of this thesis lies in its presentation of empirical evidence of the socio-spatial outcomes of school choice, the results are placed in the context of relevant theoretical perspectives. The study finds that the proportion of children transferring to out-of-catchment secondary school has increased between 1991 and 1995 but that any increase in parental choice is constrained by a variety of factors that interact in complex ways to produce substantial socio-spatial variation in its expression. It is concluded that policy and practice relating to school choice can substantially affect educational equity and efficiency. It is recommended that the operation of local education markets be more closely monitored by LEAs and that GIS analysis, as used in this study, is an important tool for this purpose.

No description available.

M.Sc. (Med.), Faculty of Health Sciences, University of the Witwatersrand, 2009 / Background Assessing risk of schistosomiasis requires knowledge of the spatial distribution of the disease and its association with demographic, socioeconomic, behavioural, and environmental factors over time and space. The objective of this study was to advance such knowledge by analyzing the spatial distribution of schistosoma haematobium infections in relation to the demographic attributes and environmental covariates of the Africa centre Demographic Surveillance Areas (DSA) in rural KwaZulu-Natal. The study also examined the association between household socio-economic conditions and rates of S. haematobium infection with particular emphasis on the impact of pipe water on rates of infection. Methods The study is a crosses sectional study, involving all 33 primary schools in Africa Centre DSA. 2110 grade five and six children took part in the study. Statistical analysis was done using chi square tests to compare statistical significant differences between sex and age groups. Bivariate and multivariate logistic regression models were used to explore factors that are significantly associated with infection. Spatial analysis was done to examine the spatial distribution of the disease using geographical information systems techniques. Microscopic analysis of the urine samples was done using the filtration technique. Results Of the 2110 school children who were screened for infection, 347 tested positive for the presence of iv S. haematobium, representing an overall prevalence of 16.6%. Prevalence levels were higher in boys (20.8%) than females (8.5%) (P<0.001). 57.6% were heavily infected (eggs ≥50 eggs per 10ml urine) as compared to 42.5% who had light infection (eggs<50 eggs/10ml of urine). Whereas, prevalence was significantly age-dependent (Pearson chi2 (3) = 28.4184, P< 0.001), intensity of infection was not significantly age dependent (Pearson chi2 (3) = 3.2579, P<0.354). Altitudinal variation, access to portable water, toilet, and distance to water bodies were significantly associated with infection. Prevalence of infection was clustered around the Eastern part of the study area. Conclusion While there may be several factors associated with schistosoma infection in the study area's school children; age, sex, water contact behaviour, homestead altitude and distance to permanent water bodies, were the most significant risk factors explaining the spatial distribution of S. haematobium infection in the Africa Centre DSA. Selective Mass treatment of S. haematobium infection in 7 clustered areas is recommended for the control of the disease.