Data Preparation and Processing of Driving Forces Weighting Factors Calculation of Driving Forces

25

2.4. Result and Discussion

2.4.1. Data Preparation and Processing of Driving Forces

Neighbourhood effect, distance to road, UHI and slope with the value less than 15 were used as a driving forces for urban growth development. Neighbourhood effect was simulated from actual urban in 1991 to get neighbourhood value in year 2000. Village potential statistics data in 1991 and 2000 was calculated using scalogram methods to get value of UHI. Distance from road was calculated using exponential decay function, whereas slope less than 15 was derived from DEM SRTM with spatial resolution 90 M. Constraint area in the study area including: protected forest, slope greater than 15 , open green space and water body. All of the data has been converted into raster data with spatial resolution 100 x 100 m, and then converted again to point vector data. The linier scale transformation method was applied to get standardized score from each criteria. The result from this calculation are all of the data value will be range from 0 – 1 which 1 is maximum value. Figure 2.7 until 2.10 was shown spatial distribution of driving forces. Whereas, Figure 2.11 was shown constraints area in study area. Figure 2.7 Neighbourhood Effect 26 Figure 2.8 Road Network Effect Figure 2.9 Slope Effect 27 Figure 2.10 UHI Effect Figure 2.11 Constraint Area 28

2.4.2. Weighting Factors Calculation of Driving Forces

Map overlay technique using intersection between developments of built-up area in 1991- 2000 and driving forces neighbourhood effect, UHI, Slope and Distance from Road were used to get average value for each driving forces. Ranking method was applied to calculate of weighted for each driving forces. Table 2.7 show the result and calculation process to get weighted for each driving forces. Based on the result of weighted calculation in Table 2.7, neighbourhood effect is the most important influence factors in built-up area development during 1991 – 2000 in study area. The weighted was contributing 48 for urban development. This condition was agreed with the theory, urban development usually takes place first in the adjacent area to the developed built-up area. The others important influences factors in built-up area development process are distance from road, UHI and slope. Closer the distances from the roads having an effect to increase new development of built-up area. This condition was contributing about 24 weighted influence in built- up area development during 1991 - 2000. Table 2.7 Weighted for Driving Forces using Ranking methods Driving forces Average Rank Sum Straight Rank Reciprocal Weight 1rj Normalized Weight Neighbourhood Effect 0.786 1 1.000 0.48 Urban Hierarchy Index 0.591 4 0.250 0.12 Slope 0.638 3 0.333 0.16 Road Network Effect 0.705 2 0.500 0.24 Total 2.083 1 Ordinarily, built-up area will grow where there are flatten areas. In this study, slope effect was contributing 16 weighted influence in built-up area development. Amount of services facilities and number of public facilities in a region is once factor that affected in build-up area development. Scalogram method was applied to derive urban hierarchy index based on amount of services and number of public facilities in a region. The result from urban hierarchy index analysis contributes for about 12 in urban development during 1991 – 2000. 29

2.4.3. Change Detection in Bandung Area