Experiences on Development and Design of STACK Problems for Circuit Analysis

STACK (System for Teaching and Assessment using a Computer Algebra Kernel) is an open-source assessment system for mathematics and related fields. At University of Vaasa, STACK has been used in courses of Mathematics and now it has been implemented in Electrical Engineering. This paper discusses experiences on development and design of various Circuit Analysis problems in STACK environment including student feedback. The starting point for developing problems here is that they do not include much calculation; instead the problems focus more on the representation of equations. The problems are designed to provide essential visual assistance to the students by drawing pictures, such as circuit diagrams by using JSXGraph library that is supported by STACK. With the help of JSXGraph, designer can draw various geometrical figures according to IEC 60617 standard. One important function in STACK is that it immediately gives automated feedback to the students depending on their answers. For this reason, a so-called potential response tree (PRT) is created for every problem. The PRT usually consists of several nodes, which compare whether specified conditions are fulfilled. The PRT can further be developed into a more complex one, which examines not only frequent but even rare errors made by students. These assets and learning tools seem to create a powerful basis for interactive learning process, where visual aids are used in solving Circuit Analysis problems in Moodle.