논문 상세보기
측정도구의 환기여부가 기온측정의 정확성에 미치는 효과
Effect of Ventilation of Measuring Device on Accuracy of Air Temperature Data
- 언어ENG
- URLhttps://db.koreascholar.com/Article/Detail/325719
Urban green spaces can mitigate negative impacts of urban heat island effect by creating cooling buffer zones. These cooling areas improve micro-climatic conditions and human health. Green space is important to reducing urban air temperature maxima and variation. Thus, there is an expectation that small green spaces (SGs) provide high cooling effects and thus make air temperatures drop. Meanwhile, such an effect in urban areas has been under-explored and needs more detailed spatial and temporal data. The purpose of the study was to develop a measurement method to detect temperature of various SGs with TVC and find the effect of TVC on accuracy of measured air temperature data in comparison with other non ventilation devices. We updated the cad file of the study site through comparing it with Google Map and conducting field surveys on the site. Transect survey was required to build a measurement route. We toured the study site by walk repeatedly to get the optimistic route which would have enough data points. One of considered routes which were inside of the forest and could make us get significantly influencing data was not founded for no trails so excluded in our study. After the field survey, we observed the study routes through a digital camcorder (Gopro) and recorded them on the cad file of the site because these data points should include air temperature and time data in their attribute table. As for transect survey, a researcher walked through the defined routes and collected air temperature data with two TVCs every second and two Testo loggers covered by aluminum foil every minute at the height of 1.5m from the ground. Stationary survey was conducted with two TVCs in every second data collection and two Testo loggers covered by aluminum foil in every minute data collection on the resting area at the entrance of the site. One of TVCs and one of Testo loggers were set at the height of 0.5m while the others of TVCs and Testo loggers were at the height of 1.5m. On the stationary point, other microclimate variables such as wind velocity, wind direction and solar irradiance were also measured and recorded every minute. We repeated the measurement for one day or two days a month (November, 2016 ~ May, 2017) and four times a day. The measuring days were selected when they were clean and calm. As a result, air temperature from TVCs was entirely lower than that from Testo loggers on the stationary survey. This trend was shown during the day rather than after sunset. The difference of air temperature from between TVCs and Testo loggers ranged from 2 ℃ after sunset to 5 ℃ at 16h. At the height of 0.5m, a Testo logger's data showed much higher than a TVC's data. These results show that Testo loggers tend to be easily influenced by the change of solar radiation. Moreover, there was the ventilation effect at the stationary. So no ventilation could be the main reason why Testo loggers' data were high. However, TVCs' lower temperature explains how effectively these devices block the solar radiation and ventilate air inside the cylinder.
