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Abstract: Topological relations are one of the most important aspects in GIS modeling. The topological relations between crisp spatial objects have been well identified. However, the topological relations between fuzzy spatial objects need more investigation. This paper deals with building a special fuzzy topological space for fuzzy sets. Based on it, a formal definition of simple fuzzy region is given. A 4×4-intersection and furthermore a 5×5-intersection approach are proposed for the formalism of topological relations. Finally 152 topological relations between two simple fuzzy regions are identified based on the 4×4-intersection approach in R 2. [Copyright &y& Elsevier]

Abstract: This research analyses the suburban expansion in the metropolitan area of Tehran, Iran. A hybrid model consisting of logistic regression model, Markov chain (MC), and cellular automata (CA) was designed to improve the performance of the standard logistic regression model. Environmental and socio-economic variables dealing with urban sprawl were operationalised to create a probability surface of spatiotemporal states of built-up land use for the years 2006, 2016, and 2026. For validation, the model was evaluated by means of relative operating characteristic values for different sets of variables. The approach was calibrated for 2006 by cross comparing of actual and simulated land use maps. The achieved outcomes represent a match of 89% between simulated and actual maps of 2006, which was satisfactory to approve the calibration process. Thereafter, the calibrated hybrid approach was implemented for forthcoming years. Finally, future land use maps for 2016 and 2026 were predicted by means of this hybrid approach. The simulated maps illustrate a new wave of suburban development in the vicinity of Tehran at the western border of the metropolis during the next decades. [Copyright &y& Elsevier]

Abstract: In this paper, Shanghai city, the biggest city in China, was selected as the case for quantifying the impact of land-use/land cover (LULC) change on patterns of surface urban heat island (UHI). Time series of LULC maps of Shanghai were produced from Landsat TM/ETM+ images between 1997 and 2008, during which this city experienced unprecedented urban growth. The results show that dramatic changes in LULC have occurred, with loss of cropland, forest and shrub to urban use. The built-up land increased by 219.50%. In contrast, bare land, cropland, fallow land, forest and shrub decreased by 79.38%, 50.50%, 43.35%, and 20.90%, respectively. Consequently, these drastically altered the land surface characteristics and spatiotemporal patterns of UHI. According to temporal analysis on seasonal and inter-annual variations of intensity of the UHI (UHII), both the mean UHII between the city center (UHIIC-R) and UHII between the peri-urban and surrounding rural areas (UHIIP-R) reached maximum during summer period, followed by UHIIC-R and UHIIP-R during spring period. UHIIC-R and UHIIP-R were both relatively weak during winter period. In contrast, UHIIC-R and UHIIP-R were both slight during autumn period. Spatially, there were significant LSTs gradients from the city center to surrounding rural areas. Furthermore, the overall relationships between surface UHI pattern and pixel-based biophysical features as well as population density and road density were quantitatively explored. Thus, based on temporal–spatial analysis of land use dynamics, patterns of LST, and socioeconomic driving forces, our findings highlight the urgent demands for planers and decision-makers to deliberately take urban expansion, UHI effects, and their impact on local climate change into account in future planning. [Copyright &y& Elsevier]