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We have conducted an education project to communicate the wave energy concept to high school students. A virtual reality system that combines both hardware and software is developed in this project to simulate the buoy-wave interaction. This first-of-its-kind wave energy unit is portable and physics-based, allowing students to conduct a number of hands-on activities. This system is the core component of an educational experience that integrates demonstration and hands-on learning, with an aim of introducing the wave energy conversion process to students in an interactive environment. Presentations have been made at two different high schools with diverse student populations, and students involved in this project rated very positively about their learning experience. As revealed by their feedback, the virtual environment and its combination with the hardware are the most important factors that help students to appreciate the knowledge in the wave energy conversion process.

We investigated changes in the prevalence of speeding during March–June 2020, the beginning of the COVID-19 pandemic, in Virginia. Vehicle speed data from 506 permanent speed counter stations around the state collected during March–June 2019 and March–June 2020 were analyzed. Increases in the proportion of vehicles traveling at least 5 mph and 10 mph above the speed limit were greatest on urban interstates and other freeways, during early morning (6:00–8:59 a.m.) and afternoon commuting hours (3:00–5:59 p.m.) on weekdays, and during afternoons (12:00–5:59 p.m.) on weekends. Logistic regression revealed that the risk of speeding by at least 5 mph increased in 2020 by 22% and by at least 10 mph increased 51% after accounting for road type, time of day, day of week, and traffic volume, relative to 2019. Future research should continue to identify where and when speeding problems are most severe, and countermeasures should be directed to the roads and time periods with the largest speeding problems. [ABSTRACT FROM AUTHOR]

Background and aims: A quantitative understanding of how carbon budgets shift throughout old-field succession is lacking and we provided estimates of annual net ecosystem production (NEP) and net primary production (NPP) for six successional sites. Methods: We utilized 4 years of field measurements of herbaceous and shrub biomass, 2 years of field measurements of tree diameters, 3 years of field measurements of soil surface CO flux, and allometric relations to estimate NEP (2006) and NPP (2004-2006) for six successional sites ranging from 5 years to 90 years old in the Shenandoah Valley, Virginia. Results: NEP of the two late successional sites (1,366 g C/m and 883 g C/m) was significantly greater than that of the two early successional fields (−209 g C/m and 16 g C/m) in 2006. Net primary production (NPP) also increased from early to late succession. The results follow the proposed conceptual model that successional ecosystems are carbon sources at the beginning of secondary succession and then become carbon sinks, but the progression is not linear. Conclusions: This study suggests that the switching point of secondary succession from releasing carbon to sequestering carbon in a temperate, humid climate is approximately between 5 and 19 years following agricultural abandonment. [ABSTRACT FROM AUTHOR]