Surveying and Geoinformatics - Scholarly Publications

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    Open Access
    Evolving a Comprehensive Geomatics Multi-Criteria Evaluation Index Model for Optimal Pipeline Route Selection
    (Taylor & Francis Online, 2020-02-17) Hamid-Mosaku, I.A; Oguntade, F.O; Ifeanyi, V.I; Balogun, A; Jimoh, A.O
    Selection of pipeline routes is a geospatial multi-criteria evaluation problem since it involves the assessment of technical, environmental and safety-related factors that influence pipeline system operations. This study determines the optimal pipeline route for transmission of oil and gas products using the Dangote Refinery Project in Nigeria as a case study. Pertinent route selection factors were identified and structured into the expert feedback model of the Analytical Network Process (ANP) for accurate prioritization. LANDSAT 8 imageries of the study area were processed and classified into various land use and land cover types, which were further modelled in ArcMap 10.2 GIS software for routing analysis. Findings reveal that the most highly prioritized factors for proper route selection were the environmental and geological factors, while the least prioritized was the economic factor. In the end, alternative Route 2 was identified as the optimal route among the four evaluated alternative routes because of its minimum route length, minimum passage length through sensitive settlement areas, and less number of river, stream and existing platforms’ crossings.
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    Open Access
    Investigation of Sediment Accumulation in Ojo Creek Channel using Geostatistical Techniques
    (Journal of Engineering Research, Faculty of Engineering, University of Lagos, 2020-09) Jimoh, O.A; Hamid-Mosaku, I.A; Oguntade, O.F; Raheem, K.A; Balogun, A
    River channels are characterized with natural processes, anthropogenic activities, geomorphology, and climate change, resulting in sediment accumulation. This consideration, however, has geomorphic impacts on riverbed, bank erosion, channel widening, sediment deposition, floodplain scour and destruction of near structures; thereby, significantly impacting on safe navigation and aquatic habitat. This paper investigates sediment accumulation in Ojo creek channel over a period of 9 years using geospatial techniques. Acquired hydrographic, bathymetry, and geospatial information of the study area were structured into spatial database for further integration with spatial analysis using geostatistical methods of Kriging/Co-kriging interpolation method in ArcGIS environment. Relative comparisons of volume of the water over the years were done for accretion and erosion. The net loss and gain in material over the years were revealed to be 1,601,251.949m3 and 1,017,252,326.841m3 respectively. Therefore, the volume of sediment calculated to be approximately 1,015,651,074.892m3. Furthermore, prediction and error analysis conducted was used to quantify the effect of sediment deposits and volume of water in the river channel. Thus, this study provides a framework for quantifying sessions of the channel that requires dredging and the amount of sand dredged for channel maintenance leading to safe navigation and good water supply.
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    Open Access
    Fuzzy MCDM-based GIS model for subsea oil pipeline route optimization: An integrated approach
    (Taylor and Francis, 2017) Balogun, A-L.; Matori, A-N.; Hamid-Mosaku, I.A.; Umar Lawal, D.; Ahmed Chandio, I.
    Proper pipeline route selection is an integral component of a typical oil exploration and transportation project. Improperly selected routes could have severe consequences including pipe failures, oil spillage, and environmental disasters. Consequently, technologies like geographic information systems (GIS) are increasingly being used to facilitate the oil pipeline route selection procedure—especially for onshore routing projects. Surprisingly, not much has been documented on the application of GIS to offshore pipeline routing. With recent discoveries on the merits of offshore oil exploration, it is necessary to extend the analytical capabilities of GIS to the unique offshore domain. However, concerns have been raised regarding the limitations of GIS in accurately prioritizing diverse selection criteria in typical multi-criteria decision-making (MCDM) problems like route selection. Consequently, this paper addresses the offshore/subsea pipeline routing constraint using a hybrid decision support system (DSS), which integrates a GIS and fuzzy logic-based approximate reasoning (AR) models for optimal performance. The resultant spatial decision support system (SDSS) was successfully applied to a case study in Malaysia. The AR algorithm calculated the significance level of the multiple criteria using various fuzzy linguistic variables and membership functions. The aggregated priority ranking from different pipeline routing experts showed that the overall influence of the environmental criteria (61.4%) significantly exceeded that of other equally important criteria in the study area. These rankings were inputted into the SDSS to simulate various probable routes. Final results accurately highlighted an optimal route, which places a premium on the protection of environmental features in the subsea study area—in alignment with the preferences of majority of the experts.
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    Open Access
    Orthogonal and Spectral Decomposition Algorithms for the Optimal Estimation of Parameters from Indirect Measurements.
    (Journal of Engineering Research, Faculty of Engineering, University of Lagos., 2018-12) ABIODUN, O.E.
    Texts attached
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    Open Access
    Application of GIS Technology to Geospatial Location of Lagos State Fire Stations, Nigeria
    (Indian Journal of Geomatics, Indian Society of Geomatics, 2018-04-01) OMOGUNLOYE, O.G.; Otavboruo, B.E.; ABIODUN, O.E.; OLUNLADE, O.A.; Emesani, E.G.
    The number of lives and properties lost to fire outbreak has heightened the need for evaluating the efficiency of fire stations within Lagos State, Nigeria. In 2016, over 16 billion naira was lost to fire in the State. This research examined the application of GIS technology to geospatial location of Lagos State fire stations and their efficiencies. The aim of this research is to evaluate fire station distributions in relation to population and economic level within Lagos State using GIS technology. This evaluation provides various analyses to support efficient planning of fire services and identify areas that are less serviced within Lagos State. To accomplish this aim, graphical representation, Euclidean buffers, and network analyst, closest to facility mapping tool were used. The main data used were; Lagos State base map, XY coordinates of commercial/industrial buildings, thirty-four fire stations, (Federal, state and privately owned), and road network of Lagos State. The study revealed that within 1km coverage area, these thirty-four (34) fire stations owned by Lagos State (14 fire stations), Federal (8 fire stations) and Privately owned (18 fire stations) are insufficient for efficient service in the populated areas of Lagos state. The paper recommends need for more geospatially located fire stations in the populated areas of Lagos State for enhancing and achieving better and safe environments.