The Factors Optimization on Georeferencing Analogue Maps

Abstract

The cadastral maps that have been produced in Turkey to date are based on different coordinate systems, map scales, map sheets and measurement methods; however, a great number of these maps are not digital. Today, advances in information systems have made it necessary to digitize these data. For this purpose, the georeferencing technique is commonly used, in which coordinates are transformed between the scanned image and reference coordinate systems. This method is mostly preferred in engineering applications. The accuracy of georeferencing is affected by several factors related to mapping, digitizing and evaluation processes. Experimental designs are widely used to examine the effect of these factors on the response variable. The response surface methodology (RSM) methods are widely used for determining the optimum value of factors and the effects of factors on the response variable. The study was carried out while resolution of scanned maps (DPI), map scale (MS) and the common point number (CPN) are selected as factors and the standard deviation (SD) selected as response variable to determine the optimal factors for accurate georeferencing. To this end, the effect of and interactions between the DPI, MS and CPN were investigated, and their optimum values were obtained using the Box-Behnken method, one of the RSM methods. The optimum conditions for MS and CPN were determined as 1/1000 and 8, respectively.