To my father and my mother. ACKNOWLEDGMENTS Firstly, I would like to appreciate my advisor Dr. Zh... more To my father and my mother. ACKNOWLEDGMENTS Firstly, I would like to appreciate my advisor Dr. Zhixin Miao who supported me for the past three years. I would especially appreciate an excellent opportunity that he gave me to not only do research on hot topics and publish high quality papers, but also to teach graduate and undergraduate level courses that improved my teaching experience significantly. I would also like to appreciate Dr. Lingling Fan who has a wide range of research interests and sharp insights, she always was available to help and always was motivating me to do better, which truly helped me.
In this study technical efficiency of broiler producers was measured in Southern Khorasan using d... more In this study technical efficiency of broiler producers was measured in Southern Khorasan using data evolvement analysis. To do so, two stage sampling method was used. The sample size was 186. The data was collected through filling up questionnaires and then analyzed by ...
This paper presents a small-signal modeling of cascaded H-bridge converter connected to a solar p... more This paper presents a small-signal modeling of cascaded H-bridge converter connected to a solar photovoltaic (PV) system. By analyzing eigenvalues of state-space equations of the system, the closed-loop controller has been designed to control the DC-link voltage in each cell as well as the grid current. The sensitivity and stability margins of the system have been examined by changing the grid impedance, capacitors of DC-link, and parameters of the controller. Also, the dynamic response of the system was analyzed by applying a step change in the DC-link setpoints. To verify the performance and effectiveness of the controllers, simulation has been conducted in MATLAB/SIMULINK for a three-phase cascaded H-bridge with three cells in each phase.
Real-time electricity prices are announced by utility companies as a part of demand response prog... more Real-time electricity prices are announced by utility companies as a part of demand response programs to ensure the lowest total cost of service for the customers. Under the real-time pricing strategy, the risk of price variation is shared between the customer and the service provider; therefore, residential customers can reduce their electricity payment through proper scheduling of the major energy consumption equipment. In residential complexes, chiller units are one of the major contributors to the buildings’ overall energy consumption; consequently, optimal scheduling of their operation can be a promising step toward reducing the operational cost. In this study, a robust optimization method is developed for optimal operation of the multi-chiller system with chilled-water storage unit considering the uncertainty associated with the predicted real-time prices. The proposed method is evaluated on a case study consisting of four multi-chiller unit and one chilled-water storage unit to investigate the operational cost variation. Simulations are conducted in GAMS software, where the results showed that the proposed method can reduce the operational cost deviation resulted by uncertainty in electricity rates.
This data presented in this article was collected using simulations on a microgrid system to anal... more This data presented in this article was collected using simulations on a microgrid system to analyze reduction of carbon footprints using distributed battery storage devices. Analysis was performed over a 24-h period of operation of the microgrid system to reduce the CO 2 emissions from 0% to 100% using battery storage devices. The data can be used in designing efficient microgrid systems, understanding the potential of battery energy storage devices in future electricity generation, and sizing the microgrid systems depending of the CO 2 reduction goals in power systems.
2020 52nd North American Power Symposium (NAPS), 2021
This paper presents a small-signal modeling of cascaded H-bridge converter connected to a solar p... more This paper presents a small-signal modeling of cascaded H-bridge converter connected to a solar photovoltaic (PV) system. By analyzing eigenvalues of state-space equations of the system, the closed-loop controller has been designed to control the DC-link voltage in each cell as well as the grid current. The sensitivity and stability margins of the system have been examined by changing the grid impedance, capacitors of DC-link, and parameters of the controller. Also, the dynamic response of the system was analyzed by applying a step change in the DC-link setpoints. To verify the performance and effectiveness of the controllers, simulation has been conducted in MATLAB/SIMULINK for a three-phase cascaded H-bridge with three cells in each phase.
This data presented in this article was collected using simulations on a microgrid system to anal... more This data presented in this article was collected using simulations on a microgrid system to analyze reduction of carbon footprints using distributed battery storage devices. Analysis was performed over a 24-h period of operation of the microgrid system to reduce the CO 2 emissions from 0% to 100% using battery storage devices. The data can be used in designing efficient microgrid systems, understanding the potential of battery energy storage devices in future electricity generation, and sizing the microgrid systems depending of the CO 2 reduction goals in power systems.
IEEE Transactions on Instrumentation and Measurement, 2007
A cryogenic 7-mm coaxial noise standard at 77.35 K has been designed and constructed. A ferrite c... more A cryogenic 7-mm coaxial noise standard at 77.35 K has been designed and constructed. A ferrite composite-matched termination was used as a thermal noise source in the frequency range of 4.5-18 GHz. The noise temperature of the noise standard has been determined by measuring the temperature distribution and attenuation constant of a thermally isolated coaxial line and the attenuation of
In this study examined the impact of electric fields and different exposure time in the yield com... more In this study examined the impact of electric fields and different exposure time in the yield component and some physical treatments canola seeds (Brassica napus L.) of SLM046 cultivar. Experiments were done in agriculture Engineering research Farm of Aboureihan Campus-Pakdasht, ...
Basic rheological property (force relaxation) of a single kernel of chickpea under uni-axial comp... more Basic rheological property (force relaxation) of a single kernel of chickpea under uni-axial compression was studied. Information on the force relaxation behaviour of chickpea kernels is not available. Meanwhile, no papers was found to study the effects of number of loadings on stress relaxation behaviour of grains and fruits. In this study the effects of moisture content and number of loadings were studied on force relaxation behaviour of chickpea kernels. The results showed that the chickpea kernels had a time dependent behaviour similar to other viscoelastic materials. The three-term Maxwell model with a maximum relative difference (MRD) of £5% and R 2 higher than 0.997 was chosen as the best fit equation to the relaxation data. Moisture content had a decreasing effect on the first term of the three-term Maxwell model (F 1 , t 1), but the number of loadings had an increasing effect on the first term of the Maxwell model. For all moisture contents and number of loadings, the grain tissue dissipates a major proportion of the initially applied force at a relatively slow rate. As the number of loading increases, the kernel becomes more elastic. Consequently, more force was required to maintain a certain deformation level. A master curve was proposed to determine the force relaxation behaviour of the chickpea kernels at moisture contents between 6.7 and 18% for 1 to 9 cycles of loadings. The Peleg and Pollak model was unsatisfactory for representing the relaxation force for chickpea kernels. K e y w o r d s: chickpea, relaxation force, rheology, stress
Agricultural Engineering International: The CIGR Journal, Dec 1, 2004
Relaxation force properties of single sea buckthorn berries under uni-axial compression were stud... more Relaxation force properties of single sea buckthorn berries under uni-axial compression were studied. Sea buckthorn berries had a time dependent behavior similar to other viscoelastic materials. The three-term Maxwell model with a maximum relative difference (MRD) of % 5 ≤ was chosen as the best fit equation to the relaxation data. For both Indian Summer and Sinensis cultivars, the firmness (as evidenced by the decay forces) decreased with temperature. As berry temperature increased from 4.5 to 34.5°C, F 1 decreased 32.9 and 19.9% for the Indian Summer and Sinensis cultivars, respectively. Sinensis berries were significantly firmer than Indian Summer berries. For each cultivar, a master curve was proposed to determine the relaxation data of the sea buckthorn berries at temperatures between 4.5 and 34.5°C. Deformation level and loading velocity had a decreasing effect on relaxation time, but temperature had an increasing effect.
Participants in electricity markets face a substantial amount of uncertainty, and with increased ... more Participants in electricity markets face a substantial amount of uncertainty, and with increased penetration of volatile renewable generation this uncertainty has further increased. Conventionally designed electricity markets cope with uncertainty by running two markets: a market that is cleared ahead of time, followed by a real-time balancing market to reconcile actual realizations of demand and available generation. In such mechanisms, the initial clearing process does not take into account the distribution of outcomes in the balancing market. Recently, an alternative so-called stochastic settlement market has been proposed (see, e.g., Pritchard et al. 2010 [Pritchard G, Zakeri G, Philpott A (2010) A single-settlement, energy-only electric power market for unpredictable and intermittent participants.
A pressurized jet of air was employed for extracting juice and juice sacs (CJJS) from halved citr... more A pressurized jet of air was employed for extracting juice and juice sacs (CJJS) from halved citrus fruits. The results showed that air pressure, nozzle diameter, the number of passes, and route of the nozzle all had significant effects on percentage of removed CJJS (PRJS). The air pressure had the greatest effect on PRJS while the nozzle diameter had the least. The PRJS was the highest at nozzle diameter of 3 mm and the least at nozzle diameter of 2.5 mm. The most effective route of the nozzle for extracting CJJS was a figure of eight route. Air pressures of 300 and 400 kPa were operative enough to remove whole juice sacs from citrus fruits. The mean values of measured impingement loads for air pressures of 300, 400, and 600 kPa were found to be 2.42, 3.25, and 5.06 N, respectively. Impingement force increased with nozzle diameter.
In this research, effects of magnetic field strength (400, 500 and 600 mT) and type of water (dis... more In this research, effects of magnetic field strength (400, 500 and 600 mT) and type of water (distilled and saline water) was studied on germination and growth characteristic of wheat seeds. Results showed that the magnetic field intensity and type of treated water had significant effects on germination and growth characteristic of wheat seeds. The morphological properties of treated plants were improved compared with controlled ones. Experimental results showed that germination rate of the seeds treated by 400 mT using distilled water had the highest amount (53.3%) and it was the lowest (20%) for control seeds using groundwater. Distilled water affected in 400 mT field and control groundwater resulted in the highest and lowest amounts of root length (155.3 and 20.0 mm, respectively). Seedling fresh weight had the highest amount for treated distilled water with 600 mT magnetic field.
International Journal of Food Properties, Mar 29, 2011
Mechanical property data of pomegranate fruits are limited. The objective of this study was to de... more Mechanical property data of pomegranate fruits are limited. The objective of this study was to determine the compression and cutting properties of whole fruit as well as the puncture strength of peel samples of fruit at different storage times. The results showed that storage time ...
This paper shows the ability of artificial neural network (ANN) technology for predicting the cor... more This paper shows the ability of artificial neural network (ANN) technology for predicting the correlation between farinographic properties of wheat flour dough and its chemical composition. The input parameters of the neural networks (NN) were the four most important chemical parameters influencing farinographic properties, namely protein content, wet gluten, sedimentation value and falling number. The output parameters of the NN models were six farinographic properties including water absorption, dough development time, dough stability time, degree of dough softening after 10 and 20 min and valorimeteric value. Results showed that, the Multi Layer ANN with training algorithm of back propagation (BP) was the best one for creation of non-linear mapping between input and output parameters. The ANN model predicted the farinographic properties of wheat flour dough with average RMS 10.794. These results show that the ANN can potentially be used to estimate farinographic parameters of dough from chemical composition. This development may have significant potential to improve product quality and reduce time and costs by minimizing farinographical experiments.
Wood in storage is exposed to both periodic water absorption and desorption (drying) processes. U... more Wood in storage is exposed to both periodic water absorption and desorption (drying) processes. Understanding water absorption and desorption in wood are of practical importance since they also affects the mechanical properties of the product. In this study, the water absorption and desorption kinetics of three varieties of wood were determined. Two kinds of models were considered to describe the kinetics: the Peleg and a new introduced model. The absorption and desorption data were fitted to Fick’s model to determine water diffusivity. The mean values of water absorption coefficient at the initial stages of water absorption for genotypes of Afra, Malach, and Roosi were determined equal to 0.019, 0.0064, and 0.008 (kg m s), respectively. Corresponding mean values for the entire soaking process were determined equal to 0.009, 0.0047, and 0.004 (kg m s), respectively. The calculated diffusion coefficients for Afra, Malach, and Roosi varieties were obtained to be 2.19×10, 4.07×10, and 5.17×10 m s, respectively. The results showed that the new introduced model was more accurate for describing the water absorption and desorption characteristics of wood samples. The maximum value of root-mean-square deviation was 5.72 which demonstrate the suitability of the new model for modeling the absorption demonstrate data.
To my father and my mother. ACKNOWLEDGMENTS Firstly, I would like to appreciate my advisor Dr. Zh... more To my father and my mother. ACKNOWLEDGMENTS Firstly, I would like to appreciate my advisor Dr. Zhixin Miao who supported me for the past three years. I would especially appreciate an excellent opportunity that he gave me to not only do research on hot topics and publish high quality papers, but also to teach graduate and undergraduate level courses that improved my teaching experience significantly. I would also like to appreciate Dr. Lingling Fan who has a wide range of research interests and sharp insights, she always was available to help and always was motivating me to do better, which truly helped me.
In this study technical efficiency of broiler producers was measured in Southern Khorasan using d... more In this study technical efficiency of broiler producers was measured in Southern Khorasan using data evolvement analysis. To do so, two stage sampling method was used. The sample size was 186. The data was collected through filling up questionnaires and then analyzed by ...
This paper presents a small-signal modeling of cascaded H-bridge converter connected to a solar p... more This paper presents a small-signal modeling of cascaded H-bridge converter connected to a solar photovoltaic (PV) system. By analyzing eigenvalues of state-space equations of the system, the closed-loop controller has been designed to control the DC-link voltage in each cell as well as the grid current. The sensitivity and stability margins of the system have been examined by changing the grid impedance, capacitors of DC-link, and parameters of the controller. Also, the dynamic response of the system was analyzed by applying a step change in the DC-link setpoints. To verify the performance and effectiveness of the controllers, simulation has been conducted in MATLAB/SIMULINK for a three-phase cascaded H-bridge with three cells in each phase.
Real-time electricity prices are announced by utility companies as a part of demand response prog... more Real-time electricity prices are announced by utility companies as a part of demand response programs to ensure the lowest total cost of service for the customers. Under the real-time pricing strategy, the risk of price variation is shared between the customer and the service provider; therefore, residential customers can reduce their electricity payment through proper scheduling of the major energy consumption equipment. In residential complexes, chiller units are one of the major contributors to the buildings’ overall energy consumption; consequently, optimal scheduling of their operation can be a promising step toward reducing the operational cost. In this study, a robust optimization method is developed for optimal operation of the multi-chiller system with chilled-water storage unit considering the uncertainty associated with the predicted real-time prices. The proposed method is evaluated on a case study consisting of four multi-chiller unit and one chilled-water storage unit to investigate the operational cost variation. Simulations are conducted in GAMS software, where the results showed that the proposed method can reduce the operational cost deviation resulted by uncertainty in electricity rates.
This data presented in this article was collected using simulations on a microgrid system to anal... more This data presented in this article was collected using simulations on a microgrid system to analyze reduction of carbon footprints using distributed battery storage devices. Analysis was performed over a 24-h period of operation of the microgrid system to reduce the CO 2 emissions from 0% to 100% using battery storage devices. The data can be used in designing efficient microgrid systems, understanding the potential of battery energy storage devices in future electricity generation, and sizing the microgrid systems depending of the CO 2 reduction goals in power systems.
2020 52nd North American Power Symposium (NAPS), 2021
This paper presents a small-signal modeling of cascaded H-bridge converter connected to a solar p... more This paper presents a small-signal modeling of cascaded H-bridge converter connected to a solar photovoltaic (PV) system. By analyzing eigenvalues of state-space equations of the system, the closed-loop controller has been designed to control the DC-link voltage in each cell as well as the grid current. The sensitivity and stability margins of the system have been examined by changing the grid impedance, capacitors of DC-link, and parameters of the controller. Also, the dynamic response of the system was analyzed by applying a step change in the DC-link setpoints. To verify the performance and effectiveness of the controllers, simulation has been conducted in MATLAB/SIMULINK for a three-phase cascaded H-bridge with three cells in each phase.
This data presented in this article was collected using simulations on a microgrid system to anal... more This data presented in this article was collected using simulations on a microgrid system to analyze reduction of carbon footprints using distributed battery storage devices. Analysis was performed over a 24-h period of operation of the microgrid system to reduce the CO 2 emissions from 0% to 100% using battery storage devices. The data can be used in designing efficient microgrid systems, understanding the potential of battery energy storage devices in future electricity generation, and sizing the microgrid systems depending of the CO 2 reduction goals in power systems.
IEEE Transactions on Instrumentation and Measurement, 2007
A cryogenic 7-mm coaxial noise standard at 77.35 K has been designed and constructed. A ferrite c... more A cryogenic 7-mm coaxial noise standard at 77.35 K has been designed and constructed. A ferrite composite-matched termination was used as a thermal noise source in the frequency range of 4.5-18 GHz. The noise temperature of the noise standard has been determined by measuring the temperature distribution and attenuation constant of a thermally isolated coaxial line and the attenuation of
In this study examined the impact of electric fields and different exposure time in the yield com... more In this study examined the impact of electric fields and different exposure time in the yield component and some physical treatments canola seeds (Brassica napus L.) of SLM046 cultivar. Experiments were done in agriculture Engineering research Farm of Aboureihan Campus-Pakdasht, ...
Basic rheological property (force relaxation) of a single kernel of chickpea under uni-axial comp... more Basic rheological property (force relaxation) of a single kernel of chickpea under uni-axial compression was studied. Information on the force relaxation behaviour of chickpea kernels is not available. Meanwhile, no papers was found to study the effects of number of loadings on stress relaxation behaviour of grains and fruits. In this study the effects of moisture content and number of loadings were studied on force relaxation behaviour of chickpea kernels. The results showed that the chickpea kernels had a time dependent behaviour similar to other viscoelastic materials. The three-term Maxwell model with a maximum relative difference (MRD) of £5% and R 2 higher than 0.997 was chosen as the best fit equation to the relaxation data. Moisture content had a decreasing effect on the first term of the three-term Maxwell model (F 1 , t 1), but the number of loadings had an increasing effect on the first term of the Maxwell model. For all moisture contents and number of loadings, the grain tissue dissipates a major proportion of the initially applied force at a relatively slow rate. As the number of loading increases, the kernel becomes more elastic. Consequently, more force was required to maintain a certain deformation level. A master curve was proposed to determine the force relaxation behaviour of the chickpea kernels at moisture contents between 6.7 and 18% for 1 to 9 cycles of loadings. The Peleg and Pollak model was unsatisfactory for representing the relaxation force for chickpea kernels. K e y w o r d s: chickpea, relaxation force, rheology, stress
Agricultural Engineering International: The CIGR Journal, Dec 1, 2004
Relaxation force properties of single sea buckthorn berries under uni-axial compression were stud... more Relaxation force properties of single sea buckthorn berries under uni-axial compression were studied. Sea buckthorn berries had a time dependent behavior similar to other viscoelastic materials. The three-term Maxwell model with a maximum relative difference (MRD) of % 5 ≤ was chosen as the best fit equation to the relaxation data. For both Indian Summer and Sinensis cultivars, the firmness (as evidenced by the decay forces) decreased with temperature. As berry temperature increased from 4.5 to 34.5°C, F 1 decreased 32.9 and 19.9% for the Indian Summer and Sinensis cultivars, respectively. Sinensis berries were significantly firmer than Indian Summer berries. For each cultivar, a master curve was proposed to determine the relaxation data of the sea buckthorn berries at temperatures between 4.5 and 34.5°C. Deformation level and loading velocity had a decreasing effect on relaxation time, but temperature had an increasing effect.
Participants in electricity markets face a substantial amount of uncertainty, and with increased ... more Participants in electricity markets face a substantial amount of uncertainty, and with increased penetration of volatile renewable generation this uncertainty has further increased. Conventionally designed electricity markets cope with uncertainty by running two markets: a market that is cleared ahead of time, followed by a real-time balancing market to reconcile actual realizations of demand and available generation. In such mechanisms, the initial clearing process does not take into account the distribution of outcomes in the balancing market. Recently, an alternative so-called stochastic settlement market has been proposed (see, e.g., Pritchard et al. 2010 [Pritchard G, Zakeri G, Philpott A (2010) A single-settlement, energy-only electric power market for unpredictable and intermittent participants.
A pressurized jet of air was employed for extracting juice and juice sacs (CJJS) from halved citr... more A pressurized jet of air was employed for extracting juice and juice sacs (CJJS) from halved citrus fruits. The results showed that air pressure, nozzle diameter, the number of passes, and route of the nozzle all had significant effects on percentage of removed CJJS (PRJS). The air pressure had the greatest effect on PRJS while the nozzle diameter had the least. The PRJS was the highest at nozzle diameter of 3 mm and the least at nozzle diameter of 2.5 mm. The most effective route of the nozzle for extracting CJJS was a figure of eight route. Air pressures of 300 and 400 kPa were operative enough to remove whole juice sacs from citrus fruits. The mean values of measured impingement loads for air pressures of 300, 400, and 600 kPa were found to be 2.42, 3.25, and 5.06 N, respectively. Impingement force increased with nozzle diameter.
In this research, effects of magnetic field strength (400, 500 and 600 mT) and type of water (dis... more In this research, effects of magnetic field strength (400, 500 and 600 mT) and type of water (distilled and saline water) was studied on germination and growth characteristic of wheat seeds. Results showed that the magnetic field intensity and type of treated water had significant effects on germination and growth characteristic of wheat seeds. The morphological properties of treated plants were improved compared with controlled ones. Experimental results showed that germination rate of the seeds treated by 400 mT using distilled water had the highest amount (53.3%) and it was the lowest (20%) for control seeds using groundwater. Distilled water affected in 400 mT field and control groundwater resulted in the highest and lowest amounts of root length (155.3 and 20.0 mm, respectively). Seedling fresh weight had the highest amount for treated distilled water with 600 mT magnetic field.
International Journal of Food Properties, Mar 29, 2011
Mechanical property data of pomegranate fruits are limited. The objective of this study was to de... more Mechanical property data of pomegranate fruits are limited. The objective of this study was to determine the compression and cutting properties of whole fruit as well as the puncture strength of peel samples of fruit at different storage times. The results showed that storage time ...
This paper shows the ability of artificial neural network (ANN) technology for predicting the cor... more This paper shows the ability of artificial neural network (ANN) technology for predicting the correlation between farinographic properties of wheat flour dough and its chemical composition. The input parameters of the neural networks (NN) were the four most important chemical parameters influencing farinographic properties, namely protein content, wet gluten, sedimentation value and falling number. The output parameters of the NN models were six farinographic properties including water absorption, dough development time, dough stability time, degree of dough softening after 10 and 20 min and valorimeteric value. Results showed that, the Multi Layer ANN with training algorithm of back propagation (BP) was the best one for creation of non-linear mapping between input and output parameters. The ANN model predicted the farinographic properties of wheat flour dough with average RMS 10.794. These results show that the ANN can potentially be used to estimate farinographic parameters of dough from chemical composition. This development may have significant potential to improve product quality and reduce time and costs by minimizing farinographical experiments.
Wood in storage is exposed to both periodic water absorption and desorption (drying) processes. U... more Wood in storage is exposed to both periodic water absorption and desorption (drying) processes. Understanding water absorption and desorption in wood are of practical importance since they also affects the mechanical properties of the product. In this study, the water absorption and desorption kinetics of three varieties of wood were determined. Two kinds of models were considered to describe the kinetics: the Peleg and a new introduced model. The absorption and desorption data were fitted to Fick’s model to determine water diffusivity. The mean values of water absorption coefficient at the initial stages of water absorption for genotypes of Afra, Malach, and Roosi were determined equal to 0.019, 0.0064, and 0.008 (kg m s), respectively. Corresponding mean values for the entire soaking process were determined equal to 0.009, 0.0047, and 0.004 (kg m s), respectively. The calculated diffusion coefficients for Afra, Malach, and Roosi varieties were obtained to be 2.19×10, 4.07×10, and 5.17×10 m s, respectively. The results showed that the new introduced model was more accurate for describing the water absorption and desorption characteristics of wood samples. The maximum value of root-mean-square deviation was 5.72 which demonstrate the suitability of the new model for modeling the absorption demonstrate data.
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Papers by Javad Khazaei