Surveying and Geoinformatics - Scholarly Publications

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Browsing Surveying and Geoinformatics - Scholarly Publications by Author "Abiodun, O. E."

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    Open Access
    Principal component analysis of urban expansion drivers in greater Lagos, Nigeria
    (Nigerian Journal of Environmental Science and Technology (NIJEST), 2017) Abiodun, O. E.; Olaleye, J. B.; Olusina, J. O.; Omogunloye, O.G.
    Urban expansion has been identified as a major cause of global climatic and environmental changes. Accurate and up-to-date information about urban expansion in terms of the drivers responsible for this expansion are important for long term planning and sustainable urban development. Lagos is one of the cities that have undergone rapid urban enlargement in the last few decades and, many factors have been adduced to contribute to its sprawling. Therefore, this study aims at using the Principal Component Analysis (PCA) for identifying the principal drivers of urban expansion in greater Lagos. In this study, a set of fourteen (14) drivers of expansion are considered in a multinucleic structure. A sequence of Landsat images of the study area for 1984, 2001, 2006 and 2013 was acquired and processed to six land use classes: dense, moderate urban, water, vegetation, wetland and mangrove. The study area was partitioned into 25 regular cells of 20km by 25km each from where proximate driver values were obtained. The effectiveness of each driver was tested using PCA. The results show that Land Availability accounted for 37.836% of total variance. This result of this study may form the basis for a renewed attention on land policy in the study area as a way to enhance sustainable development.
  • Item
    Open Access
    Surveyors and the challenges of digital surveying and mapping technology
    (American Association for Geodetic Surveying, 2011) Olaleye, J. B.; Abiodun, O. E.; Olusina, J. O.; Alademomi, A. S.
    The advent of digitalization has brought revolutionary changes to the methods and instrumentation of surveying and it appears that the initial training and special qualities of the surveyor are no longer a precondition for the practice of surveying. Nowadays, many tools and techniques have been developed or improved upon for the acquisition of survey data with a high degree of accuracy, flexibility, simplicity, and cost reduction. This development poses new challenges for the traditional surveyor who needs to cope with the new trend. This paper discusses a very brief history of surveying. The innovations in surveying are discussed under the following headings: land surveying, remote sensing, hydrographic surveying, map-data processing, and data communication. Some important challenges facing the surveyor due to these innovations are highlighted. The paper also attempts to identify the responses surveyors could adopt. It is suggested in this paper that adaptive learning and retraining will help the modern surveyor but the best response will be "reprofessionalization".