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Predicting of Urban Growth Pattern Using Logistic Regression Model in Gorgan Area النص الكامل
2015
galdavi, somayeh | mohammadzadeh, marjan | salman mahiny, abdolrassoul | najafi nejad, ali
Modeling urban development patterns is an important technique for understanding complex urban growth processes. In this study, Logistic Regression model was conducted to model urban growth pattern of Gorgan area in North Iran, during the period 1988-2025. To do this, remotely sensed imagery of years 1988, 1998 and 2007 were used to produce land use maps. Also, dependent and independents variables were created to perform urban growth pattern modeling. Then, urban changes were detected during 1988 – 2007 and urban change modelling was achieved using Logistic Regression. After that, future urban grow pattern was predicted. The results indicated that urban areas have increased during study time period. Validation of model results was performed using Pseudo-R2 and ROC values which were more than 0.27and 0.83 respectively. Furthermore, Logistic Regression was applied to predict urban growth patterns for the years of 2016 and 2025. According to the results, appropriate implementations are needed to control land use changes, particularly urban growth, in order to preserve environmental as well as ecological balances of the area. The result could be help the managers to monitor and prevent the unplanned urban development in future. Model’s extracted maps can be used for managing and controlling future urban development.
اظهر المزيد [+] اقل [-]Planform channel dynamics and bank migration hazard assessment of a highly sinuous river in the north-eastern zone of Bangladesh النص الكامل
2015
Deb, Mithun | Ferreira, Celso
Rivers or watercourses in Sylhet plain of Bangladesh are very dynamic over time. The aim of the present study is to investigate the channel planform dynamics, the prediction of future lateral migration of the bankline and assessment of the hazards associated with Manu River, Bangladesh. The name Manu River represents the river study reach from Tripura, India to Moulvibazar, Bangladesh of 41.6 km. Channel contraction and expansion are very frequent in this river. Studies had shown that the sinuosity of the river varies from 1.36 to 2.48. Also the meandering ratio of the river ranges from 0.32 to 1.67. Satellite data were collected and analyzed to determine the planform characteristics, meandering parameters and bankline migration rates between 1975 and 2013. The study is based on the Landsat satellite imagery of 1975, 1988, 1999, 2003 and 2005 and aerial photograph of 2009 and 2013 which were accumulated from United States Geological Survey. Specific critical bends have been elected where bank erosion and accretion rates were severe. The purpose of this paper is to show the erosion rate, behavior and pattern of upstream side of Manu River, Bangladesh through the study period of 38 years from 1975 to 2013 by comparing its different geomorphological parameters. This study has contributed to develop a model for bankline migration prediction of the forthcoming years and address the physical hazard to provide a risk surface. Present assessment has revealed that, there are some critical regions where erosion would be up to 29.18 hectares in 2025.
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