The piezoelectric method to atomize fluids in aeroponic systems is known as a new application.In the current study,the effects of four independent variables on the misting rate were investigated.These variables were D...The piezoelectric method to atomize fluids in aeroponic systems is known as a new application.In the current study,the effects of four independent variables on the misting rate were investigated.These variables were Dosage of Chemical Fertilizer(DCF),the Height of Solution above Piezoelectric Ceramic(HSPC),Piezoelectric Location at the Bottom of the Container(PLBC),and the Container Geometry(CG).Physical properties such as fluid density,viscosity,surface tension,Total Dissolved Solids(TDS),and Electrical Conductivity(EC)of the solutions were measured.Moreover,optimization was performed to determine suitable ranges of independent variables to get the optimum value of the misting rate.Results showed that the HSPC,PLBC,and CG significantly affect the total misting rate(P<1%).Besides,the DCF,HSPC,and CG have significant effects on surface evaporation at a probability level of 1%.At the temperature of 25℃and for different concentrations of fertilizer,the density,viscosity,surface tension,TDS,and EC varied between 1002-1006.5 kg/m^(3),1.009-1.395 mPas,0.07182-0.07298 N/m,253-3397 mg/L,502-6795 mS/cm,respectively.Total misting rate ranged between 0.499 and 5.720 g/min.In the outlet of the mist generation container,mass flow rate was in the range of 59.895 to 65.116 g/min.Also,theoretically calculated mist average droplet size was in the range of 2.90 to 2.92 mm for different fertilizer doses.The present study is the first research on the factors affecting the ultrasonic mist production rate in an aeroponic system.For future developments,effect of voltage,frequency,and using horn should be investigated.Besides,similar research should be done in the field of gas-phase bioreactors(mist bioreactors).展开更多
The potential of the visible infrared(Vis–IR)(400–1100 nm)transmittance method to assess the internal quality(freshness)of intact chicken egg during storage at a temperature of 30±7C and 25±4%relative hum...The potential of the visible infrared(Vis–IR)(400–1100 nm)transmittance method to assess the internal quality(freshness)of intact chicken egg during storage at a temperature of 30±7C and 25±4%relative humidity was investigated.Two hundred chicken egg samples were used for measuring freshness and spectra collection during egg storage(up to 25 days).Two correlation models,firstly between Haugh unit(HU)and storage time,and secondly between the yolk coefficient(YC)and storage time,were developed and yielded correlation coefficients(R^2)of 0.86 and 0.96,respectively.These models spanned the period for which egg quality decreased dramatically and are statistically significant(P<0.05).In addition,to reduce the dimensionality of the spectra and extract effective wavelengths,two methods were developed based on principal component analysis(PCA)and a genetic algorithm(GA).The output of PCA and GA were also used comparatively to design an egg quality intelligent system.The result of the analyses indicated that identification ratio of GAwith fast Fourier transform(FFT)preprocessing was superior to other methods,and that the quality classification rates of this method for one-day-old eggs are 100%.This study shows that identification of an egg’s freshness using NIR spectroscopy with GA and artificial neural network(ANN)is reliable.展开更多
文摘The piezoelectric method to atomize fluids in aeroponic systems is known as a new application.In the current study,the effects of four independent variables on the misting rate were investigated.These variables were Dosage of Chemical Fertilizer(DCF),the Height of Solution above Piezoelectric Ceramic(HSPC),Piezoelectric Location at the Bottom of the Container(PLBC),and the Container Geometry(CG).Physical properties such as fluid density,viscosity,surface tension,Total Dissolved Solids(TDS),and Electrical Conductivity(EC)of the solutions were measured.Moreover,optimization was performed to determine suitable ranges of independent variables to get the optimum value of the misting rate.Results showed that the HSPC,PLBC,and CG significantly affect the total misting rate(P<1%).Besides,the DCF,HSPC,and CG have significant effects on surface evaporation at a probability level of 1%.At the temperature of 25℃and for different concentrations of fertilizer,the density,viscosity,surface tension,TDS,and EC varied between 1002-1006.5 kg/m^(3),1.009-1.395 mPas,0.07182-0.07298 N/m,253-3397 mg/L,502-6795 mS/cm,respectively.Total misting rate ranged between 0.499 and 5.720 g/min.In the outlet of the mist generation container,mass flow rate was in the range of 59.895 to 65.116 g/min.Also,theoretically calculated mist average droplet size was in the range of 2.90 to 2.92 mm for different fertilizer doses.The present study is the first research on the factors affecting the ultrasonic mist production rate in an aeroponic system.For future developments,effect of voltage,frequency,and using horn should be investigated.Besides,similar research should be done in the field of gas-phase bioreactors(mist bioreactors).
文摘The potential of the visible infrared(Vis–IR)(400–1100 nm)transmittance method to assess the internal quality(freshness)of intact chicken egg during storage at a temperature of 30±7C and 25±4%relative humidity was investigated.Two hundred chicken egg samples were used for measuring freshness and spectra collection during egg storage(up to 25 days).Two correlation models,firstly between Haugh unit(HU)and storage time,and secondly between the yolk coefficient(YC)and storage time,were developed and yielded correlation coefficients(R^2)of 0.86 and 0.96,respectively.These models spanned the period for which egg quality decreased dramatically and are statistically significant(P<0.05).In addition,to reduce the dimensionality of the spectra and extract effective wavelengths,two methods were developed based on principal component analysis(PCA)and a genetic algorithm(GA).The output of PCA and GA were also used comparatively to design an egg quality intelligent system.The result of the analyses indicated that identification ratio of GAwith fast Fourier transform(FFT)preprocessing was superior to other methods,and that the quality classification rates of this method for one-day-old eggs are 100%.This study shows that identification of an egg’s freshness using NIR spectroscopy with GA and artificial neural network(ANN)is reliable.
