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Modern Geomatics Technologies and Applications




















                                       (a)                                     (b)

                                    Fig 3. (a) natural logarithm of road, (b) square root of river


               The distance from road parameter was considered dynamic and expandable in the time series, so that it was first classified
                                         st
                                                         nd
          into 3 levels, includiing: basic roads, 1  grade roads, and 2  grade roads. Historical behaviour between 2002 and 2008 and the
                                                                   st
          earth's digital elevation model were used as training dataset. Then, the 2  grade side roads have become the 1  grade side roads
                                                                                                 st
                 st
          and the 1  grade side roads have become the major roads, and the basic ways were expandable at the beginning and the end using
          two conditions: a) Minimum gradient in the direction of the slope of the area, and b) Maximum change potential.
               Firstly,  the  map  of  distance  from  road  for  the  target  year  was  predicted  with  this  method,  then  it  was  used  as  an
          independent factor in predicting the target year map.

          4.  Proposed Method

             4.1.  Similarity weighted instance‐based learning

               Weight-based learning method is one of the transfer potential modelling methods that follows the logic of  k-nearest
          neighbour method. This method is based on the calculation of weight distances to variable space for known samples of land use
          classes. Basically, in connection with the creation of transfer potentials to model the change in the land cover, the model considers
          two classes for each transfer (fixed pixels and variable pixels) and evaluate them. In this method, the k-nearest neighbour for
          each fixed or variable pixel (pixel with a position that it’s changes is considered for the future) is examined, and then the distances
          in the variable space from each unknown pixel to the pixels around (range k), which they have changed during the calibration
          period are calculated[7][1] (see Fig. 4).
               This distance is obtained in an exponential function in order to calculate a continuous level of membership of the existing
          land use layers (classes) for each pixel from the following equation[3]:

                                         1
                                 
                              ∑   =1 (1 −  1  )                                                             (1)
                                             
                         ℎ       ℎ          =  1 +      
                                       

          where c is the number of variable pixels in the range k, d is a linear distance to variable pixels in the range k, and K is the total
          number of variable and constant pixels in the range k.
               There are several points to note about the learning process based on the similarity weight model, which is mentioned
          below:
               •   The  difference  between  this  method  and  the  method  of  k-nearest  neighbour  is  that  this  method  considers  the
                   continuous level of the membership class instead of considering the strict value.





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