Browsing by Author "Wadembere, Ismail"

Now showing 1 - 7 of 7
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    An Algorithm for Geo-Spatial Objects Adjustment
    (Advances in Geomatics Research (, 2015) Wadembere, Ismail; Ogao, Patrick
    GIS practitioners always integrate geo-spatial data from different sources using map-overlay operations in order to make decisions and solve queries that deal with multiple layers. But they are always faced with openings and overlaps among objects that form features in thematically same datasets resulting into slivers (unwanted small objects) and danglings (unwanted intersections, polylines, and end points). Most GIS users end up running clean and build algorithms that just remove unwanted objects but not achieving perfect merging originally intended with main reason being lack of geometrical object based algorithm that can be used to update and adjust spatial objects to eliminate discrepancies caused by geometry differences between features of thematically similar data. We present an algorithm for manipulating geometries of geospatial objects that make up datasets basing on spatial points as the simplest geometrical primitive. Our approach makes it possible to represent high level spatial geometrical shapes using points and allows for more comprehensive handling of all shapes still maintaining the simplicity of working with the point primitive. Representation of spatial geometry shapes comprising of spatial points, polylines, and polygons using spatial point primitive geometry is achieved by scanning all the spatial dataset, observing the different geometry shapes and topology that exist, then representation all shapes using points and primary attribute in form of text. The algorithm carries out shape transformation of objects so that all openings and overlaps between objects making up dataset are eliminated so that geo-processing, modeling, and analysis utilize the properly integrated datasets. The algorithm can be applied in spatial data management like geometrical alignment and sharing environments like spatial data infrastructure.
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    Geometrical Spatial Data Integration in Geo-Information Management
    (Fountain Publishers, 2007) Wadembere, Ismail; Ogao, Patrick J.
    One of the reasons that Individual users and organizations use GIS, is to exchange geospatial data as a means to location based decision-making. A considerable amount of preprocessing has to be done, before and after the data has been integrated. Within this decade, we are seeing developments in technologies which are creating services which need geospatial data comparison and integration (Najar et al., 2006). This is so evident in: Google Earth; Microsoft’s MapPoint.Net; O’Reilly’s Where 2.0; Intergraph’s reorganization around “SIM”; Oracle Locator and Spatial; ESRI’s ArcGIS 9.x; US Census’ MAF/TIGER integration; new platforms, new vendors, new users and the many conferences on mobile commerce and locationbased services (Batty, 2004, Alperin, 2005) and varying application (Busgeeth and Rivett, 2004). These developments and changes are so diverse that they don’t even seem related, but they are (Sonnen, 2005); that is, they take advantage of the vast geo-information available, which reflect the increased importance of location in information systems and services (Strader et al., 2004).
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    Geometry Adjustment for Geospatial Data Integration
    (WORLDCOMP’10 Conference, 2010) Wadembere, Ismail; Ogao, Patrick
    As many mapping organizations are updating geospatial databases with new data about our rapidly changing world, there are challenges of how to effectively and quickly to adjust the geometries so that there are no openings and overlaps due to variation between different versions of same data and neighboring features. The paper describes an approach of geospatial geometry adjustment basing on paradigm of point as being the simplest and smallest spatial primitive to manipulate and to define all geospatial data. Every unique identifiable spatial instance in form of point is given an identifier and it is this that is manipulated during geometry adjustment to transfer updates from the source/reference data to the data set being adjusted. This approach solves the issue of slivers and dangling which are always created during data merging and differences that are always brought into databases due to variations in data capture, storage, and manipulation.
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    Geometry Updating for Geospatial Data Integration
    (International Archives of Photogrammetry and Remote Sensing, 2010) Wadembere, Ismail; Ogao, Patrick
    Lots of geospatial data has been collected within the last decades due to advances in digital spatial data capturing technologies and this has brought in different versions of the same data sets. Although various spatial and mapping organizations are updating and revising geospatial databases with new data/information about our rapidly changing environment; there are challenges of how to effectively and quickly update and adjust the geometries so that there are no sliver and dangling issues as a result of opening and overlaps due to variation between different versions of same data. This is vital in geospatial data updating and management in geosystems and databases. The paper describes an approach of geospatial geometry updating and adjustment basing on paradigm of point as being the simplest and smallest spatial primitive to handle and that it can be manipulated to define all geospatial data elements. It integrates methodologies from both earth sciences and computer science. Every unique identifiable spatial instance in form of point is given an identifier and it is this that is manipulated during geometry adjustment to transfer updates from the source/reference data to the data set being updated/adjusted. This approach solves the issue of silvers and dangling which are always created during data merging and the differences that are always brought into databases due to variations in data capture, storage, and manipulation approaches.
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    Overcoming Object Misalignment in Geo-Spatial Datasets
    (Journal of Geographic Information System, 2014) Wadembere, Ismail; Ogao, Patrick
    In integrating geo-spatial datasets, sometimes layers are unable to perfectly overlay each other. In most cases, the cause of misalignment is the cartographic variation of objects forming features in the datasets. Either this could be due to actual changes on ground, collection, or storage approaches used leading to overlapping or openings between features. In this paper, we present an alignment method that uses adjustment algorithms to update the geometry of features within a dataset or complementary adjacent datasets so that they can align to achieve perfect integration. The method identifies every unique spatial instance in datasets and their spatial points that define all their geometry; the differences are compared and used to compute the alignment parameters. This provides a uniform geo-spatial features’ alignment taking into consideration changes in the different datasets being integrated without affecting the topology and attributes.
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    Peri-Urbanisation Pressure on Customary Land Tenure System and its Management: A Case Study of Kasese Municipality
    (J. Eng, 2019) Masereka, Philly; Wadembere, Ismail
    Today’s world is rapidly urbanizing, with radical urban expansion in developing countries. Rapid rate ofurbanization has led to an increasing demand for more land for housing, industrial, commercial and agricultural purposes. This land is not available within the already planned cities but at the peripherals where the unplanned customary land is being converted to urban land at a faster rate. This impacts on the periurban in terms of changes in land use new forms of household composition, differential access to urban benefits (such as health infrastructure and employment) and increased pressure on land. Current research has mainly focused on the effects of urban sprawl on land cover dynamics hence studies on peri-urbanization and its management on customary tenure system is limited. Therefore, this study focused on examining the nature of developments and how to manage peri-urbanization on customary land in Kasese municipality, Uganda. Used a descriptive research design which uses both qualitative and quantitative methods of data collection and a sample of 88 respondents were selected using purposive, stratified and simple random sampling techniques with the questionnaires and interview guides as the data collection tools. Aerial photographs for the period 1998-2018 were used to compute spatial-temporal changes in the extends of the municipality as a result of urbanization. The study revealed that majority of the developments in the peri-urban parishes are temporally (42.0%) and semi-permanent (40.9%) while permanent structures were only (17%) this is attributed to many factors for example tenure insecurity. It was also found out that majority 86.4% of the respondents did not get plan approval from municipal council to build and this explains the development of unplanned houses which have led to growth of informal settlements. This research through literature suggested and recommended the use of land readjustment an inclusive and equitable peri-urban land development tool that can meet the needs of local peri-urban communities for proper peri-urban land administration and management.
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    Towards a Geometrical Spatial Integration Model for GIS
    (International Journal of Computing and ICT Research, 2008) Wadembere, Ismail; Ogao, Patrick J.
    Geospatial information systems provide avenues to fulfill users’ quest for both absolute and relative locations of features/objects. To achieve this, the users need to have access to different geospatial data sets from various sources. This calls for integration of data from different geospatial sources. But, there are shortcomings as different data sets may not map exactly onto one another, one of reasons being the difference in features’ geometry. This paper presents a conceptual model for geospatial data integration that can identify and measure differences and adjust spatial geometries of geospatial features to form meaningful objects which can be used for geo-spatial analysis, modeling, and easy geo-information management.