Abstract
Free-hand drawing of graphical elements using the mouse is one of most user-friendly methods. In non-visual communication, graphical elements can be easily expressed using tactile communication tools; however, these methods are not competent in expressing properties and relations of graphical contents in elementary geometry. Graphical elements are most optimally recognized using inputted hand-written curves. Corner detection is a complex technique, which serves an important role in these recognitions. We describe recognition aspects in inputted graphical contents of elementary geometry, and improve the break-bend judgment using Choquet's integral like evaluation functions and generic algorithms. Our learning method and the corresponding normalization method are made universal, and can be applied to other problems.