The Experts below are selected from a list of 270 Experts worldwide ranked by ideXlab platform
Javad Behmanesh - One of the best experts on this subject based on the ideXlab platform.
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the application of multiple linear regression method in reference evapotranspiration trend calculation
Stochastic Environmental Research and Risk Assessment, 2018Co-Authors: Neda Khanmohammadi, Hossein Rezaie, Majid Montaseri, Javad BehmaneshAbstract:Trend analysis of reference evapotranspiration (ET0), as a key factor in irrigation programming, has an important role in water resources management. Many parameters affect ET0 and their variations can change its values. In this paper, the effect of temporal variation of meteorological variables including wind speed, temperature, solar radiation and Saturation Vapor Pressure deficit on temporal variations of ET0 was analyzed. Trend analysis of ET0 and its more effective meteorological parameters was accomplished in 30 synoptic stations which are located in Iran using Spearman’s Rho test. The multiple linear regressions were also used to determine the relationship between ET0 trend and the trend of its more effective parameters. Increasing and decreasing trends in ET0 were obtained at annual and seasonal scales. Many studied stations which had decreasing trend in the annual and seasonal periods have been located in the arid climates while all stations which have been located in humid and very-humid climates, had an increasing trend in annual and seasonal periods. The trend results in studied variables showed that annual and seasonal values of wind speed, temperature and Saturation Vapor Pressure deficit decrease however the values of solar radiation increases in most studied stations. Multiple linear regressions results demonstrated that ET0 trend can be calculated by the trend of two more effective variables including wind speed and Saturation Vapor Pressure deficit.
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The application of multiple linear regression method in reference evapotranspiration trend calculation
Stochastic Environmental Research and Risk Assessment, 2017Co-Authors: Neda Khanmohammadi, Hossein Rezaie, Majid Montaseri, Javad BehmaneshAbstract:Trend analysis of reference evapotranspiration (ET0), as a key factor in irrigation programming, has an important role in water resources management. Many parameters affect ET0 and their variations can change its values. In this paper, the effect of temporal variation of meteorological variables including wind speed, temperature, solar radiation and Saturation Vapor Pressure deficit on temporal variations of ET0 was analyzed. Trend analysis of ET0 and its more effective meteorological parameters was accomplished in 30 synoptic stations which are located in Iran using Spearman’s Rho test. The multiple linear regressions were also used to determine the relationship between ET0 trend and the trend of its more effective parameters. Increasing and decreasing trends in ET0 were obtained at annual and seasonal scales. Many studied stations which had decreasing trend in the annual and seasonal periods have been located in the arid climates while all stations which have been located in humid and very-humid climates, had an increasing trend in annual and seasonal periods. The trend results in studied variables showed that annual and seasonal values of wind speed, temperature and Saturation Vapor Pressure deficit decrease however the values of solar radiation increases in most studied stations. Multiple linear regressions results demonstrated that ET0 trend can be calculated by the trend of two more effective variables including wind speed and Saturation Vapor Pressure deficit.
Neda Khanmohammadi - One of the best experts on this subject based on the ideXlab platform.
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the application of multiple linear regression method in reference evapotranspiration trend calculation
Stochastic Environmental Research and Risk Assessment, 2018Co-Authors: Neda Khanmohammadi, Hossein Rezaie, Majid Montaseri, Javad BehmaneshAbstract:Trend analysis of reference evapotranspiration (ET0), as a key factor in irrigation programming, has an important role in water resources management. Many parameters affect ET0 and their variations can change its values. In this paper, the effect of temporal variation of meteorological variables including wind speed, temperature, solar radiation and Saturation Vapor Pressure deficit on temporal variations of ET0 was analyzed. Trend analysis of ET0 and its more effective meteorological parameters was accomplished in 30 synoptic stations which are located in Iran using Spearman’s Rho test. The multiple linear regressions were also used to determine the relationship between ET0 trend and the trend of its more effective parameters. Increasing and decreasing trends in ET0 were obtained at annual and seasonal scales. Many studied stations which had decreasing trend in the annual and seasonal periods have been located in the arid climates while all stations which have been located in humid and very-humid climates, had an increasing trend in annual and seasonal periods. The trend results in studied variables showed that annual and seasonal values of wind speed, temperature and Saturation Vapor Pressure deficit decrease however the values of solar radiation increases in most studied stations. Multiple linear regressions results demonstrated that ET0 trend can be calculated by the trend of two more effective variables including wind speed and Saturation Vapor Pressure deficit.
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The application of multiple linear regression method in reference evapotranspiration trend calculation
Stochastic Environmental Research and Risk Assessment, 2017Co-Authors: Neda Khanmohammadi, Hossein Rezaie, Majid Montaseri, Javad BehmaneshAbstract:Trend analysis of reference evapotranspiration (ET0), as a key factor in irrigation programming, has an important role in water resources management. Many parameters affect ET0 and their variations can change its values. In this paper, the effect of temporal variation of meteorological variables including wind speed, temperature, solar radiation and Saturation Vapor Pressure deficit on temporal variations of ET0 was analyzed. Trend analysis of ET0 and its more effective meteorological parameters was accomplished in 30 synoptic stations which are located in Iran using Spearman’s Rho test. The multiple linear regressions were also used to determine the relationship between ET0 trend and the trend of its more effective parameters. Increasing and decreasing trends in ET0 were obtained at annual and seasonal scales. Many studied stations which had decreasing trend in the annual and seasonal periods have been located in the arid climates while all stations which have been located in humid and very-humid climates, had an increasing trend in annual and seasonal periods. The trend results in studied variables showed that annual and seasonal values of wind speed, temperature and Saturation Vapor Pressure deficit decrease however the values of solar radiation increases in most studied stations. Multiple linear regressions results demonstrated that ET0 trend can be calculated by the trend of two more effective variables including wind speed and Saturation Vapor Pressure deficit.
Markku Kulmala - One of the best experts on this subject based on the ideXlab platform.
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condensation eVaporation of insoluble organic Vapor as functions of source rate and Saturation Vapor Pressure
Journal of Geophysical Research, 2002Co-Authors: Liisa Pirjola, Hannele Korhonen, Markku KulmalaAbstract:[1] Condensation growth of atmospheric particles by insoluble organic Vapors was studied by a monodisperse aerosol dynamics model MONO32 including atmospheric chemistry mechanism. The source rate of the Vapor and its Saturation Vapor density at a particle surface were varied. The initial particle number size distribution was assumed to be bimodal, and aerosol was initially an internal mixture of particles consisting of soluble sulphuric acid and insoluble organic material in a ratio of 1:1. Model simulations predicted that if the ratio of the Vapor source rate and the condensation sink of particles, Q/CS, exceeded 108 cm−3 and the Vapor was nonvolatile or low volatile, the 10 nm nuclei grew with the growth rates of 2.5–3 nm h−1 and could act as cloud condensation nuclei in superSaturations of 1.6% or lower after 24 h simulation. Then the Vapors must have Saturation Vapor Pressures less than 7 × 106 cm−3. However, the higher the ratio of Q/CS, the higher the Saturation Vapor Pressure could be. When the Vapor was highly volatile, i.e., the Saturation Vapor density was high enough, in our simulations greater than 6 × 107 cm−3 the Ostwald ripening was observed. Then the nucleation mode particles were not able to grow but coagulated with larger particles without causing any significant impact on climate. An analytical expression for the Saturation Vapor density for the Ostwald ripening (cOst) was derived as a function of the ratio of Q/CS. Sensitivity tests for the accommodation coefficient and thermodynamic parameters as well as their effects on cOst were investigated.
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Condensation/eVaporation of insoluble organic Vapor as functions of source rate and Saturation Vapor Pressure
Journal of Geophysical Research: Atmospheres, 2002Co-Authors: Liisa Pirjola, Hannele Korhonen, Markku KulmalaAbstract:[1] Condensation growth of atmospheric particles by insoluble organic Vapors was studied by a monodisperse aerosol dynamics model MONO32 including atmospheric chemistry mechanism. The source rate of the Vapor and its Saturation Vapor density at a particle surface were varied. The initial particle number size distribution was assumed to be bimodal, and aerosol was initially an internal mixture of particles consisting of soluble sulphuric acid and insoluble organic material in a ratio of 1:1. Model simulations predicted that if the ratio of the Vapor source rate and the condensation sink of particles, Q/CS, exceeded 108 cm−3 and the Vapor was nonvolatile or low volatile, the 10 nm nuclei grew with the growth rates of 2.5–3 nm h−1 and could act as cloud condensation nuclei in superSaturations of 1.6% or lower after 24 h simulation. Then the Vapors must have Saturation Vapor Pressures less than 7 × 106 cm−3. However, the higher the ratio of Q/CS, the higher the Saturation Vapor Pressure could be. When the Vapor was highly volatile, i.e., the Saturation Vapor density was high enough, in our simulations greater than 6 × 107 cm−3 the Ostwald ripening was observed. Then the nucleation mode particles were not able to grow but coagulated with larger particles without causing any significant impact on climate. An analytical expression for the Saturation Vapor density for the Ostwald ripening (cOst) was derived as a function of the ratio of Q/CS. Sensitivity tests for the accommodation coefficient and thermodynamic parameters as well as their effects on cOst were investigated.
Majid Montaseri - One of the best experts on this subject based on the ideXlab platform.
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the application of multiple linear regression method in reference evapotranspiration trend calculation
Stochastic Environmental Research and Risk Assessment, 2018Co-Authors: Neda Khanmohammadi, Hossein Rezaie, Majid Montaseri, Javad BehmaneshAbstract:Trend analysis of reference evapotranspiration (ET0), as a key factor in irrigation programming, has an important role in water resources management. Many parameters affect ET0 and their variations can change its values. In this paper, the effect of temporal variation of meteorological variables including wind speed, temperature, solar radiation and Saturation Vapor Pressure deficit on temporal variations of ET0 was analyzed. Trend analysis of ET0 and its more effective meteorological parameters was accomplished in 30 synoptic stations which are located in Iran using Spearman’s Rho test. The multiple linear regressions were also used to determine the relationship between ET0 trend and the trend of its more effective parameters. Increasing and decreasing trends in ET0 were obtained at annual and seasonal scales. Many studied stations which had decreasing trend in the annual and seasonal periods have been located in the arid climates while all stations which have been located in humid and very-humid climates, had an increasing trend in annual and seasonal periods. The trend results in studied variables showed that annual and seasonal values of wind speed, temperature and Saturation Vapor Pressure deficit decrease however the values of solar radiation increases in most studied stations. Multiple linear regressions results demonstrated that ET0 trend can be calculated by the trend of two more effective variables including wind speed and Saturation Vapor Pressure deficit.
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The application of multiple linear regression method in reference evapotranspiration trend calculation
Stochastic Environmental Research and Risk Assessment, 2017Co-Authors: Neda Khanmohammadi, Hossein Rezaie, Majid Montaseri, Javad BehmaneshAbstract:Trend analysis of reference evapotranspiration (ET0), as a key factor in irrigation programming, has an important role in water resources management. Many parameters affect ET0 and their variations can change its values. In this paper, the effect of temporal variation of meteorological variables including wind speed, temperature, solar radiation and Saturation Vapor Pressure deficit on temporal variations of ET0 was analyzed. Trend analysis of ET0 and its more effective meteorological parameters was accomplished in 30 synoptic stations which are located in Iran using Spearman’s Rho test. The multiple linear regressions were also used to determine the relationship between ET0 trend and the trend of its more effective parameters. Increasing and decreasing trends in ET0 were obtained at annual and seasonal scales. Many studied stations which had decreasing trend in the annual and seasonal periods have been located in the arid climates while all stations which have been located in humid and very-humid climates, had an increasing trend in annual and seasonal periods. The trend results in studied variables showed that annual and seasonal values of wind speed, temperature and Saturation Vapor Pressure deficit decrease however the values of solar radiation increases in most studied stations. Multiple linear regressions results demonstrated that ET0 trend can be calculated by the trend of two more effective variables including wind speed and Saturation Vapor Pressure deficit.
Hossein Rezaie - One of the best experts on this subject based on the ideXlab platform.
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the application of multiple linear regression method in reference evapotranspiration trend calculation
Stochastic Environmental Research and Risk Assessment, 2018Co-Authors: Neda Khanmohammadi, Hossein Rezaie, Majid Montaseri, Javad BehmaneshAbstract:Trend analysis of reference evapotranspiration (ET0), as a key factor in irrigation programming, has an important role in water resources management. Many parameters affect ET0 and their variations can change its values. In this paper, the effect of temporal variation of meteorological variables including wind speed, temperature, solar radiation and Saturation Vapor Pressure deficit on temporal variations of ET0 was analyzed. Trend analysis of ET0 and its more effective meteorological parameters was accomplished in 30 synoptic stations which are located in Iran using Spearman’s Rho test. The multiple linear regressions were also used to determine the relationship between ET0 trend and the trend of its more effective parameters. Increasing and decreasing trends in ET0 were obtained at annual and seasonal scales. Many studied stations which had decreasing trend in the annual and seasonal periods have been located in the arid climates while all stations which have been located in humid and very-humid climates, had an increasing trend in annual and seasonal periods. The trend results in studied variables showed that annual and seasonal values of wind speed, temperature and Saturation Vapor Pressure deficit decrease however the values of solar radiation increases in most studied stations. Multiple linear regressions results demonstrated that ET0 trend can be calculated by the trend of two more effective variables including wind speed and Saturation Vapor Pressure deficit.
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The application of multiple linear regression method in reference evapotranspiration trend calculation
Stochastic Environmental Research and Risk Assessment, 2017Co-Authors: Neda Khanmohammadi, Hossein Rezaie, Majid Montaseri, Javad BehmaneshAbstract:Trend analysis of reference evapotranspiration (ET0), as a key factor in irrigation programming, has an important role in water resources management. Many parameters affect ET0 and their variations can change its values. In this paper, the effect of temporal variation of meteorological variables including wind speed, temperature, solar radiation and Saturation Vapor Pressure deficit on temporal variations of ET0 was analyzed. Trend analysis of ET0 and its more effective meteorological parameters was accomplished in 30 synoptic stations which are located in Iran using Spearman’s Rho test. The multiple linear regressions were also used to determine the relationship between ET0 trend and the trend of its more effective parameters. Increasing and decreasing trends in ET0 were obtained at annual and seasonal scales. Many studied stations which had decreasing trend in the annual and seasonal periods have been located in the arid climates while all stations which have been located in humid and very-humid climates, had an increasing trend in annual and seasonal periods. The trend results in studied variables showed that annual and seasonal values of wind speed, temperature and Saturation Vapor Pressure deficit decrease however the values of solar radiation increases in most studied stations. Multiple linear regressions results demonstrated that ET0 trend can be calculated by the trend of two more effective variables including wind speed and Saturation Vapor Pressure deficit.
