Predicting evaporation rate is one of important elements for hydrology planning. There are several methods to estimate evaporation from a water surface. The objective of this study was to test the capability of artifi...Predicting evaporation rate is one of important elements for hydrology planning. There are several methods to estimate evaporation from a water surface. The objective of this study was to test the capability of artificial neural networks （ANNs） to predict evaporation using 10 years data set （1999 to 2008） from Ahvaz meteorological station and has been compared with values obtained using pan evaporation. Software Qnet 2000 has been utilized to model the evaporation. The Qnet 2000 was trained with monthly climate data （Solar radiation, minimum and maximum temperature, minimum and maximum relative humidity, and wind velocity） as input. The model was approximately implemented 144 times that finally hyperbolic secant stimulant function of 4 input parameters including minimum temperature, maximum temperature, solar radiation and wind velocity and 6 nodes in hidden layer has been yielded the best outcome. Correlation coefficients （R2） in training and testing sections are to 97.4% and 97.3% respectively. Also maximum errors in training and testing sections equaled to 18% and 24% respectively. Results showed ANNs approach works well for the data set used in this region.展开更多
The paper aims to investigate the potential of a water body to influence in lowering the warmth in the city of Sao Jose do Rio Preto, Brazil, due to the evaporative cooling effects. In order to verify its potential, t...The paper aims to investigate the potential of a water body to influence in lowering the warmth in the city of Sao Jose do Rio Preto, Brazil, due to the evaporative cooling effects. In order to verify its potential, three collecting points of temperature and humidity were placed in an urban area close to the municipal dam. The first one was placed on the dam margin, the second one, 50 m distant of the margin and, the third one, 100 m distant. The data were taken during December 2010 and then compared to the climate data of the Climate Station of CIIAGRO-Integrated Center of Agro Meteorological. The results show that the closer the collection point is to the water body, and the lower is the temperature variation. The humidity taxes verified at the closest point to the water body indicate values higher than those ones collected at the most distant point. The insertion of moisture through the water bodies in an urban environment demonstrated to be a strategy that improved the thermal conditions and has to be considered for urban planners to establish strategies of urban occupation.展开更多
文摘Predicting evaporation rate is one of important elements for hydrology planning. There are several methods to estimate evaporation from a water surface. The objective of this study was to test the capability of artificial neural networks （ANNs） to predict evaporation using 10 years data set （1999 to 2008） from Ahvaz meteorological station and has been compared with values obtained using pan evaporation. Software Qnet 2000 has been utilized to model the evaporation. The Qnet 2000 was trained with monthly climate data （Solar radiation, minimum and maximum temperature, minimum and maximum relative humidity, and wind velocity） as input. The model was approximately implemented 144 times that finally hyperbolic secant stimulant function of 4 input parameters including minimum temperature, maximum temperature, solar radiation and wind velocity and 6 nodes in hidden layer has been yielded the best outcome. Correlation coefficients （R2） in training and testing sections are to 97.4% and 97.3% respectively. Also maximum errors in training and testing sections equaled to 18% and 24% respectively. Results showed ANNs approach works well for the data set used in this region.
文摘The paper aims to investigate the potential of a water body to influence in lowering the warmth in the city of Sao Jose do Rio Preto, Brazil, due to the evaporative cooling effects. In order to verify its potential, three collecting points of temperature and humidity were placed in an urban area close to the municipal dam. The first one was placed on the dam margin, the second one, 50 m distant of the margin and, the third one, 100 m distant. The data were taken during December 2010 and then compared to the climate data of the Climate Station of CIIAGRO-Integrated Center of Agro Meteorological. The results show that the closer the collection point is to the water body, and the lower is the temperature variation. The humidity taxes verified at the closest point to the water body indicate values higher than those ones collected at the most distant point. The insertion of moisture through the water bodies in an urban environment demonstrated to be a strategy that improved the thermal conditions and has to be considered for urban planners to establish strategies of urban occupation.
