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This chapter describes learning electromagnetism with visualizations and focuses on the value of concrete and visual representations in teaching abstract concepts. We start with a theoretical background consisting of three subsections: visualization in science, simulations and microcomputerbased laboratory, and studies that investigated the effectiveness of simulations and real-time graphing in physics. We then present the TEAL (Technology Enabled Active Learning) project for MIT’s introductory electromagnetism course as a case in point. We demonstrate the various types of visualizations and how they are used in the TEAL classroom. A description of a large-scale study at MIT follows. In this study, we investigated the effects of introducing 2D and 3D visualizations into an active learning setting on learning outcomes in both the cognitive and affective domains. We conclude by describing an example of TEAL classroom discourse, which demonstrates the effects and benefits of the TEAL project in general, and the active learning and visualizations in particular.

The term ‘genomics’ broadly refers to the study of the genome, or the complete genetic inheritance of an organism. The genome sequence of an organism provides the equivalent of a complete genetic map; yet, knowledge of the sequence itself does not reveal how this map manifests itself into the physical characteristics or phenotypes observed for an organism. Genomics research is dependent upon comparative analyses of extraordinary volumes of data. Whilst visualizations may facilitate the significance and understanding of such comparisons, the complexity and scope of the information provides a challenge for the classroom learner. This chapter examines the roles of representations in genomics ‘visual literacy’, and addresses the challenges associated with distilling a rapidly progressing research area into pedagogical frameworks that can accommodate the dynamic nature of the field. The chapter also presents an application of visualizations in genomics education within the context of a tertiary level international collaborative research project. The student-centred project, ‘Visualizing the Science of Genomics’, presents a novel example of inquiry-based teaching in genomics in an online environment.

Visualization is an essential skill in undergraduate geology courses as it is for expert geologists. Geology students and geologists must visualize the shape of the land from topographic maps, the three-dimensional geometry of geologic structures from limited exposures, and the geologic history recorded in sequences of layers and in natural landscapes. Interactive animations have proven successful in helping college students visualize the three-dimensional nature of geology. They permit interactions that are not possible with traditional, paper-based materials, are deliverable via the Internet, and can be imbedded in modules that embrace constructivist pedagogy.

An investigation examined the value of various representations (e.g. concrete three-dimensional models, virtual computer models, static two-dimensional computer models, stereo-chemical formulas) in supporting the achievement by students of an effective perception of molecular structures. Additionally, the usefulness was studied of concrete three-dimensional models, virtual computer molecular models, and their combination, as help tools for students in solving spatial chemistry tasks involving three-dimensional perception, rotation and reflection. Altogether 477 students from secondary schools (age: 18–19 years) took part in the investigation. For purpose of the inquiry a set of four Molecular Visualization Tests was developed. Information about students` manner of thinking while solving spatial tasks was initially gained with a questionnaire and then examined in depth with a structured interview. The data was processed by methods suitable for the respective quantitative and qualitative approaches taken. The results suggest that the information sources which serve as a foundation for students’ perception of molecular structure decrease in value from concrete models, to virtual models, to static computer models. Students’ perception of three-dimensional structure was better when a stereo-chemical formula was used in comparison to that supported by a computer image. The results indicate that both molecular models types used as help-tools can ease the solving of chemistry tasks that require three-dimensional thinking. Virtual computer models seem to be as effective as concrete models, but the combined usage of both can cause splits in students’ attention and therefore seems to be less appropriate.

This chapter extends the use of cognitive and “situative” theories of learning described in our earlier chapter to discuss the design of five chemistry multimedia visualization projects. All five projects are shown to enhance the learning of chemistry concepts and development of scientific investigative process skills. Two projects emphasize the social processes associated with scientific investigation with bench laboratory components; two others without laboratory components could be easily utilized in ways that develop such social processes; and the fifth is shown to enhance visualization process skills although it was designed based upon the cognitive theory of multimedia learning. In order to assess the developing levels of visualization skills of novice chemistry students supported by all five visualization projects, nontraditional testing items must be utilized. Samples of several multimedia testing items addressing both conceptual and process skills are discussed and used in studies of the efficacy of the most cognitive-theory based project. A study using the project with the closest alignment to “situative” theory illustrates how the rubric for representational competence levels discussed in our earlier chapter is applied to show changes in visualization abilities of students. The chapter concludes with brief suggestions for future development of visualization software, visualization-based instructional activities and testing activities.

As described in Chapter 5, a finite automaton specifies a system by means of a set of states and a transition function. The arguments of the transition function are the state and event. We can speak about an actual state. The transition function assigns a state to an actual state. The assigned state is a next state while the actual state can be called the active present state. By repeating the assignments, a sequence of actual states is obtained. In the finite automaton there is always only one state active.

A system can often be broken down into subsystems. If it is required to describe activities of subsystems and their mutual relations, a finite automaton model can be cumbrous because each combination of subsystem states needs a separate state of the finite automaton. Another model known as a Petri net removes that inadequacy. Petri nets are named after a German mathematician C. A. Petri who first proposed a model of that kind (C. A. Petri, 1962). With Petri nets the main idea is to represent states of subsystems separately. Then, the distributed activities of a system can be represented very effectively. Many properties of the DEDS, , synchronization, concurrency, and choices can be well presented and analyzed using Petri nets. They can be used not only for the specification of the DEDS behavior but also the control design. However, Petri nets have various other uses.