International Conference on Computer Systems and Technologies – ComSysTech’2003
Computer-aided learning of programming
Abstract: The contribution summarizes educational aspects of computer-aided learning and analyses the opportunities of didactic software exploitation based on animation-simulation models. Applied models are oriented to specific thematic areas. Models listed in the contribution were created during former research activities of the Computer Science Department. Keywords: Computer-aided learning, e-learning of programming, interactive computer models, interactive learning.
MODELS, MODELLING, SIMULATION AND ANIMATION IN COMPUTER-AIDED LEARNING Modelling and simulation of dynamic phenomena on a computer, which are the subjects of instruction, have a great importance. Simulation not only contributes to understanding different complicated phenomena but also makes possible studying their qualities and acquiring more knowledge about them on the basis of observations. Physical experiment is often replaced by experimenting on the model. This substitution is unavoidable in the case when an examined phenomenon is not freely observable, i. e. is too fast or too slow, or the real experiment is dangerous or too expensive. The system simulation is a specific form of knowledge presentation. The system simulation is possible to use by research and also projecting of an object, but also by instruction, teaching and other occasions of announcements of knowledge and hypothesis. The object of the system simulation, are systems determined on knowledge objects and their movement (in meaning of any change in time, or space). The object of the simulation can be systems defined on objects, existing as well as projected, or systems having no relation to objective reality. The basic principle of the simulation is the formulation of conclusions about simulated system through its simulation model. The experimental method with simulated model distinguishes simulation of systems from other forms of knowledge, that’s why we consider this method in more tight meaning of the word. The utterances created on basis of their usage are valid in all phases of iteration process of the system simulation. Computers as universal instructional media together with computer simulation and animation models play an important role in the field of education especially in e-learning. Therefore methods of modelling and simulation are part of education also at some pedagogical universities oriented on computer sciences. The subject of modelling and simulation at the University of Constantine the Philosopher in Nitra plays an important role among the pedagogic universities worldwide. This subject was established since the creation of computer sciences study specialization and behind common theory of modelling discrete and continuous systems include theoretical knowledge and practical skills in creation models for educational process. The modelling and simulation is more common as an education facility. Modelling and simulation as a versatile didactic facility can be effectively used at all education levels of our school system, without respecting the type and orientation of the school. Modelling, simulation and animation is mainly a part of education in subjects of technical subjects didactics and in disciplines oriented on creation and usage of didactic aids, especially didactic software. Modelling and simulation as an education facility play an important role in education process. It is possible to distinguish three different hierarchic levels of its implementation: ? Development and usage of simulation models of education process at level of planning and organization of education process with main aim to find its best alternative with respect to specified targets in field of absolvent profile. Teaching plans
as well as particular subjects and their content are put together at this level together with inter-subject bindings, creation of organization and realization form of instruction etc. Also the education process as a unit at selected level of management is an object of simulation at this level. ? Development and usage of simulation models of education system at level of planning and organization of instruction units with goal to optimise the teacher’s activity within this process and also to make this process more efficient. The object of modelling is lesson or larger instruction unit, eventually a whole subject or course. Development and application of simulation models for demonstration, eventually research of different objects and events of the real world, which are the subjects of education process. The object of simulation is the teaching matter.
DIDACTIC COMPUTER MODELS AND BASIC DIDACTIC PRINCIPLES It is commonly accepted that the most permanent knowledge is that which is based on our own experience. Simulation models can help the user define different premises and conditions to examine the qualities of a modelled system and consequently help him acquire more knowledge about the object on which the system was defined. For modelling it is necessary to select only those objects and eliminate those phenomena for which the simulation is the most effective way of their recognition and examination. Development of models used for didactic purposes requires to complete basic didactic principles, which have common and permanent validity. However, this doesn’t mean that their content is stable and system of sentinel tags is closed. It is important to actualise and optimise this principle system according to new research in fields of psychology a pedagogic sciences. Of the most important didactic principles is the principle of scientism. According to actual ideas the principle of scientism must reflect not only in teaching matter, but also in process of its adoption, which must be adequate to modern scientific knowledge. Application of demonstration leads to creation real ideas about the object of the teaching matter. According to actual understanding of this principle, there should be used no random model of an object, but an object assuring the realization of didactic goals. A model used for didactic purposes must allow demonstration to uncover important attributes of inspected object, its inner structure, defining its elements and attributes of these elements, bindings and relations between these elements in form required by didactic goals of education process. Effectiveness in teaching will be increased when participants themselves create models of objects and do not receive them already prepared. This approach to teaching, the individual creation or a model, satisfies the didactic principle of activity. The participant has to reproduce the structure of the model, the symptoms of the model and reveal the qualities of the model during its construction and completion. In the process of simulation experiments the student gains theoretical knowledge and at the same time the room for the individual derivation of other constructs is created. The work with a prepared model can lead to two activities: either to the completion or the model (improving or expanding the model) or to the rebuilding of the model (correction). The above - mentioned active form or teaching is hardly possible without a deep knowledge, both theoretical and practical, of modelling and simulation of systems, programming and programming technologies and experiences from using other suitable tools. INTERACTIVE DIDACTIC SIMULATION AND ANIMATION MODELS IN E-LEARNING The creation of didactic computer simulation and animation models has interdisciplinary character, needs a good knowledge from the subject area, the theory of teaching, methods of teaching, pedagogy, psychology, didactic technology, programming, production of software, computers, computer graphics, multimedia etc. The
creation of professional didactic software needs corporation of the teams of experts from mentored areas. So it is not an easy task to control and organize the work of this heterogeneous group. I guess, the personality of the teacher of Computer Science can incorporate the majority of all the desired qualities of the didactic software make. If we want him to include suitable models to the teaching programs, to create computer simulation models for didactic purposes, we must arm him with certain intellectual skills and theoretical knowledge from programming, modelling, simulation, visualisation and animation and from the field of didactic software creation. For this reason subjects Programming, Modelling and simulation and Didactic software creation were introduced into the curricula at the Pedagogical University in Nitra for student of Computer Science. Parametrically controlled didactic model creation is a good theme for student projects in subject Programming and skills in programming is a necessary tool for implementation all models in subject Modelling and simulation. This way is a suitable solution of inter-subject bindings. USING DIDACTIC COMPUTER SIMULATION AND ANIMATION MODELS IN TEACHING/LEARNING PROGRAMMING In courseware for e-teaching/e-learning the subject Programming we use several didactic models as being a subject of teaching and also as a means of teaching. I want to introduce only a few of them. Sorting algorithms Sorting algorithms and their programming is an important part of subject Programming. Usage of computer interactive simulation models is suitable for quick understanding of sorting algorithms main principles and founding out their features. The user can simulate different experiments with simultaneous animation studying their qualities and acquiring more knowledge on the basis of his/her own observations. If the user wants, it is possible to study and analyse the source text of procedures, which implements the particular steps of algorithms. It is also possible to stop or make the animation faster or slower. The module includes the basic set of sorting algorithms and also a few special of them. The part of basic sorting contains: Bubble-Sort, Shaker-Sort, Shell-Sort, QuickSort, Insert-Sort, Binary-Insert-Sort and Marge-Sort. Joint Sort, Lexicographic-Sort, Sorting by Address Counting, Stack-Sort were included into set of special sort algorithms. It is very interesting and useful for educants to compare animation development of different sorts on the screen and the number of realised elementary operations (comparisons and let statements) in case of using the same input object list.
Fig. 1. The Quick-Sort model animated by sorting columns (by height) in action
Fig. 2. The Quick-Sort model animated by sorting points (by vertical parameter) in action
Fig. 3. The Lexikografic-Sort model animated by sorting numbers in action Abstract data structures A part of e-learning courseware for programming is the theme unit: Abstract data structures. We selected a few actually used dynamic abstract date structures: the linked list, the stack, the queue, the binary tree etc for the interactive model creation. Each of them contains a graphic presentation of implementation of the selected data structure by array and also by dynamic variables and pointer types. The models give a visual comparison of the difference between the array (static) and linked list (dynamic) implementation. These models allow the user to use the basic operation of the selected abstract data structure in interactive mode and monitoring the dynamic processes in which they result. In the Fig. 4 we can see the stack model in the action. The introduced didactic models are created by different programming technologies (structured programming, object oriented programming etc.) in different program languages and programming environments (Turbo Pascal, C++, Visual Basic, Delphi, GifAnimator, Flash, HTML, DHTML, DreamWeaver, etc.)
Fig. 4. The stack animation model in action CONCLUSION Didactic models are particular programming systems, or they are part of ICAL. Each topic- oriented module includes theory, mathematical model of explained event and an animation-simulation interactive model for experiment realization. Whole animation is controlled by set parameters of the mathematical model. The presentation of the results is demonstrative and easy to read. Animation of a running experiment supports understanding the fundamentals of particular methods, processes eventually events and they develop the imagination, the predictable and prognostic skills of students. They contribute to development of their ability to realize the mental experiment and to predict results of different changes of input parameters of the model and the kind of changes that must be performed to reach the required goal. Main reasons of simulation models implementation within the education are: ? ? ? Contribution to student’s motivation The lesson is more demonstrative The model includes a lot of information about the modelled object in a concentrated form and that’s why it is a suitable form for its presentation within didactic programs. They contribute to higher level of student’s knowledge. Support student’s activity (interaction) Support student’s creativity Enable realization of animation-simulation experiments (which are controllable) Increase the effectiveness of the education
? ? ? ?
All quoted advantages of animation-simulation models assume didactically correct usage of suitable models.
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