EVALUATION AND CLASSIFICATION OF MATURITY OF FRESH TOMATO FRUITS USING COLOR-BASED IMAGE ANALYSIS TECHNIQUES

Abstract

Nitrogen oxides (NOx) and carbon monoxide (CO) are the two important pollutants in the atmosphere which are particularly emitted from vehicles. In this study, assessments were made on hourly, daily, monthly and seasonal variability of the two gases along with their dependence on two atmospheric variables (temperature and relative humidity) using one year data (2016) of Addis Ababa. The data were obtained from Ethiopian Meteorological Agency, Addis Ababa. The results of the analyses show the following. Hourly variability show peaks before noon (10:00 – 12:00) and around midnight. Variability of both pollutants among days did not show patterns. But there seems to be correlation between NOx and CO concentrations on daily basis. Monthlyaveraged concentrations showed seasonal patterns with variability between dry and wet seasons. NOx concentration during wet season was about twice that of the dry season, but no such difference was observed in the case of CO. Annual dependences of the two pollutants on the two atmospheric variables, temperature and relative humidity, indicate modest negative correlation between NOx and temperature but none for CO. Seasonally CO showed correlation with temperature. NOx showed positive and CO negative, correlations with relative humidity on seasonal basis. The data for NOx during the months September to December seem to have problems and hence more year data may be needed to make reasonable conclusions.