@article {GesKorLutMat-VVADM-2005, title = {Visage {\textendash} Visualization of Algorithms in Discrete Mathematics}, journal = {Zentralblatt f{\"u}r Didaktik der Mathematik}, volume = {37}, number = {5}, year = {2005}, pages = {395-401}, abstract = {

Abstract: Which route should the garbage collectors{\textquoteright} truck take? Just a simple question, but also the starting point of an exciting mathematics class. The only "hardware" you need is a city map, given on a sheet of paper or on the computer screen. Then lively discussions will take place in the classroom on how to find an optimal routing for the truck. The aim of this activity is to develop an algorithm that constructs Eulerian tours in graphs and to learn about graphs and their properties. This teaching sequence, and those stemming from discrete mathematics, in particular combinatorial optimization, are ideal for training problem solving skills and modeling {\textendash} general competencies that, influenced by the German National Standards, are finding their way into curricula. In this article, we investigate how computers can help in providing individual teaching tools for students. Within the Visage project we focus on electronic activities that can enhance explorations with graphs and guide students even if the teacher is not available {\textendash} without taking away freedom and creativity. The software package is embedded into a standard DGS, and it offers many pre-built and teacher-customizable tools in the area of graph algorithms. Until now, there are no complete didactical concepts for teaching graph algorithms, in particular using new media. We see a huge potential in our methods, and the topic is highly requested on part of the teachers, as it introduces a modern and highly relevant part of mathematics into the curriculum.

}, keywords = {refereed}, author = {Geschke, Anne and Kortenkamp, Ulrich and Lutz-Westphal, Brigitte and Materlik, Dirk} } @article {KorMat-GTWCEUJJ-2004, title = {Geometry teaching in wireless classroom environments using {Java} and {J2ME}}, journal = {Science of Computer Programming}, volume = {53}, number = {1}, year = {2004}, month = {10}, pages = {71{\textendash}85}, abstract = {

Interactive geometry software is established as an important tool in geometry and math education. We present our research on possible ways to use such software in wireless classroom environments. In particular, we address user interface issues on portable devices and describe how we maintain a common code base for both desktop and mobile environments, thus increasing the stability of the application. We also report on our empirical data comparing different Java virtual machines that are available for portable devices using a prototype implementation of the Interactive Geometry Software Cinderella for J2ME.

}, keywords = {refereed}, doi = {10.1016/j.scico.2004.02.006}, url = {http://kortenkamps.net/papers/2004/wirelessj2me-final.pdf}, author = {Kortenkamp, Ulrich and Materlik, Dirk} } @conference {KorMat-PIGC-2004, title = {Pen-based input of geometric constructions}, booktitle = {Proceedings of MathUI 2004}, year = {2004}, abstract = {

Pen-based input is the classical approach to drawing. Without computers, using a pen was the natural approach to do drawings, and the simplicity of this "device" always called for similar electronic solutions. Today, a broad range of electronic input devices is available that try to pair the simplicity of input with the power of computing. They come in all sizes: from small touch-screens with stylus in personal digital assistants, via desktop-size input tablets or interactive displays, to electronic whiteboards with rear- or front-projection. These devices all share a direct interaction paradigm. The challenge in using these devices for geometric constructions is to automatically annotate the drawn objects with their relations to the other objects. A basic example is the drawing of a right-angled triangle: How can we automatically recognize the user{\textquoteright}s intention to have a right angle? Can we do that at all? Do we really want to do that? If not {\textendash} what is the easiest pen-compatible way to have the user add this information? We will demonstrate several approaches to these problems, implemented in a development version of Cinderella. Another interesting issue is the presentation of hand-drawn figures: Is it possible to preserve the look of a sketch while still guaranteeing mathematically correct figures? Using the additional information gathered by automatic theorem proving we show some solutions.

}, keywords = {refereed}, url = {http://kortenkamps.net/papers/2004/Scribbling-article.pdf}, author = {Kortenkamp, Ulrich and Materlik, Dirk}, editor = {Libbrecht, Paul} } @conference {KorMat-VLLM-2004, title = {Vernetztes Lehren und Lernen im Mathematikunterricht}, booktitle = {Grundfragen multimedialen Lehrens und Lernens. Tagungsband des 2. Workshops GML2004}, year = {2004}, publisher = {Alcatel SEL}, organization = {Alcatel SEL}, keywords = {refereed}, author = {Kortenkamp, Ulrich and Materlik, Dirk}, editor = {Fellbaum, Klaus and Rebensburg, Klaus and Schwill, Andreas} }