Particle Sampling and Analyses Using Computer-Based Approaches

Environmental sampling and analyses are often limited by the availability of equipment or environmental conditions. Nevertheless, there exists a need to expose students to opportunities to carry out routine data collection and analysis, to think about the plan for sampling, and to evaluate the findings. The collaborative project that is described in this paper focuses on simulation of the sampling of an air pollutant, particulate matter. Faculty at Northern Arizona University (NAU) and Arizona State University (ASU) collaborated to enhance the teaching of Air Quality Engineering (AQE) in their institutions. Basic information regarding ambient particles, including their sources, size distributions, and methods of collection were first introduced. Jointly prepared assessments including an individual knowledge assessment, a group report/reflection, in addition to the individual feedback on the activity itself provided data for analyses. Students were able to undertake the process of virtual particle sampling for a variety of sources and locations by using new tools that were created in Excel with added Visual Basic Application (VBA) routines. A resulting image of the virtually collected particles was post-processed by using a Matlab-based program that was developed specifically for this project. Both qualitative and quantitative data analyses were performed. The data analyses revealed the extent to which students were able to achieve the expected learning outcomes from the activities that were made available to the students at the two institutions. Specifically, the online assessments of content knowledge resulted in average scores of 74% (at NAU) and 89% (at ASU) on the 11-question assignment, thereby signifying good individual knowledge of the content. Additionally, students' perceptions of the activities were captured, and revealed that students found the activity interesting, engaging, and useful in promoting their learning of particles in the air. From a pedagogical perspective, this collaborative project was able to fuse traditional classroom-based basic teaching and learning of concepts with an applications-based activity in air quality engineering courses that are not set up as laboratory courses. The techniques that are discussed in this paper are ones that can be translated to other courses so that a deeper exploration of concepts and their connections may be enabled through more hands-on but flexible exploration for sampling and analyses.