Human comfort period outside and inside bamboo stands

Abstract

Four models (sine, exponential-sine, power-sine and logarithmic-sine) were conducted to fit the daily cycle of sunlight intensity inside and outside bamboo stands. Exponential-sine curve was the best among others. Since the shadowing effect inside bamboo stands, the glare is dodged and human visual comfort period increases 4.5 h longer. Sunrays radiation effect toward temperature and RH follow the sine function, while earth 's surface energy follow exponential-sine equation for open space and sine equation for inside bamboo stands. Best equations for fitting the daily cycle of temperature and RH based on sunrays radiation and earth 's surface energy effects have high coeficient of determination. According to those equations, the thermal comfort temperature period is 13 h long in open space while it is 16.5 h long inside bamboo stand. RH in both locations is high. Air inside bamboo stand is wetter. Human is much more tolerate against RH than temperature, thus temperature is dominant affecting human comfort. The hourly measurements of discomfort index prove during working hour, labor could comfortly work 1.5 h longer inside bamboo stand than in open space. Heat index measurements also show that labor would be safe from heat injury 5 h longer inside bamboo stands.© 2014 Asian Network for Scientific Information.