Highlights Smoke samples collected with UAS during rangeland prescribed burns were used to develop representative smoke emission factors for rangeland fires. The head fire emission factors of PM 2.5 and NO x were consistent with the low end of the range of flaming emission factors in the literature. The combination of high air temperatures and high absolute humidity resulted in higher levels of PM 2.5 and O 3 in smoke. Abstract. Prescribed burning is an ecological process critical to maintaining and improving rangeland ecosystems. Smoke impacts related to prescribed burning have been the subject of intense discussion and public debate. The objectives of this study were to collect accurate smoke emissions data using unmanned aircraft systems (UAS) and use the data to develop smoke emission factors representative of prescribed rangeland fires in the tallgrass prairie Flint Hills region of Kansas and Oklahoma. The emission factors will be used to improve the input parameters used in smoke modeling tools. Four prescribed burns on unique burn units were sampled for this study. Smoke emission factors were determined using the carbon mass balance method. Average emission factors for head fires were: PM 2.5 , 11.3±10.8g/kg fuel; NO x as NO, 1.4±0.9 g/kg fuel; CO 2 , 1569±28 g/kg fuel; CH 4 , 6.8±4.3 g/kg fuel; NMHC as propane, 3.3±2.5 g/kg fuel; and VOC as propane, 4.5±3.5 g/kg fuel. Compared with head fires, back fires tended to produce lower emissions of PM 2.5 but higher emissions of NO x and VOC. Green, high-moisture vegetation present during the growing season fires in September resulted in a larger head fire PM 2.5 emission factor compared to April fires. Generally, the combination of high air temperature and high absolute humidity resulted in high PM 2.5 and O 3 in smoke. Conducting prescribed fires under conditions of cool air temperature and low absolute humidity can reduce the generation of PM 2.5 and O 3 in smoke, as long as these conditions fall within the prescribed range for the burn. Keywords: Carbon mass balance, Drone, Fire, Grass, Ozone, Pasture, Prescribed burning, Rangeland management, Rangelands, Smoke emission factor, Tallgrass prairie, Unmanned aircraft system.
{"title":"Measuring Smoke Emissions from Prescribed Rangeland Burning in the Flint Hills Region Using Unmanned Aircraft Systems","authors":"Zifei Liu, Carolyn Baldwin, Douglas Watson, Jayson Prentice, Travis Balthazor, Md Ariful Haque","doi":"10.13031/ja.15430","DOIUrl":"https://doi.org/10.13031/ja.15430","url":null,"abstract":"Highlights Smoke samples collected with UAS during rangeland prescribed burns were used to develop representative smoke emission factors for rangeland fires. The head fire emission factors of PM 2.5 and NO x were consistent with the low end of the range of flaming emission factors in the literature. The combination of high air temperatures and high absolute humidity resulted in higher levels of PM 2.5 and O 3 in smoke. Abstract. Prescribed burning is an ecological process critical to maintaining and improving rangeland ecosystems. Smoke impacts related to prescribed burning have been the subject of intense discussion and public debate. The objectives of this study were to collect accurate smoke emissions data using unmanned aircraft systems (UAS) and use the data to develop smoke emission factors representative of prescribed rangeland fires in the tallgrass prairie Flint Hills region of Kansas and Oklahoma. The emission factors will be used to improve the input parameters used in smoke modeling tools. Four prescribed burns on unique burn units were sampled for this study. Smoke emission factors were determined using the carbon mass balance method. Average emission factors for head fires were: PM 2.5 , 11.3±10.8g/kg fuel; NO x as NO, 1.4±0.9 g/kg fuel; CO 2 , 1569±28 g/kg fuel; CH 4 , 6.8±4.3 g/kg fuel; NMHC as propane, 3.3±2.5 g/kg fuel; and VOC as propane, 4.5±3.5 g/kg fuel. Compared with head fires, back fires tended to produce lower emissions of PM 2.5 but higher emissions of NO x and VOC. Green, high-moisture vegetation present during the growing season fires in September resulted in a larger head fire PM 2.5 emission factor compared to April fires. Generally, the combination of high air temperature and high absolute humidity resulted in high PM 2.5 and O 3 in smoke. Conducting prescribed fires under conditions of cool air temperature and low absolute humidity can reduce the generation of PM 2.5 and O 3 in smoke, as long as these conditions fall within the prescribed range for the burn. Keywords: Carbon mass balance, Drone, Fire, Grass, Ozone, Pasture, Prescribed burning, Rangeland management, Rangelands, Smoke emission factor, Tallgrass prairie, Unmanned aircraft system.","PeriodicalId":29714,"journal":{"name":"Journal of the ASABE","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135213574","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Highlights This study designed a corn ear picking device to reduce grain loss and corn header power consumption. The fracture force of corn peduncles under different deflection angles was studied as the basis of the design. The working parameters were optimized through an orthogonal experiment. Abstract. In corn ear picking, the corn peduncles are fractured under pure tensile forces. The large force demands in the fracture brought severe grain loss, an enormous instantaneous load, and high power consumption in the corn harvest. In this paper, the fracture behavior of the corn peduncles under different tensile orientations was studied. It showed the fracture force of corn peduncle could be reduced by more than 80% when its fracture mode transformed from tensile fracture to bending fracture as long as the corn ear was deflected to the critical angle of 55°. Based on this, a corn picking device was designed to reduce peduncle fracture force by deflecting corn ears to the critical angle. The optimal parameters of the designed corn picking device were determined as follows: the diameter of the snapping rollers was 20 mm, the rotating speed of the stalk rolls was 700 rpm, and the inclination angle of the corn picking unit was 28.3°. A comparative test between the designed corn picking device and a commonly used corn picking device was performed. It showed the designed corn picking device could reduce grain loss, average power consumption, and peak power. This study will provide a theoretical basis and design reference for corn harvester design to reduce grain loss and power consumption. Keywords: Corn ear picking, Corn harvest, Corn harvester header, Fracture force, Fracture mechanics, Grain loss, Power consumption.
{"title":"Design and Experimental Study on a Corn Picking Device Based on the Fracture Mechanics of Corn Peduncle","authors":"Qiankun Fu, Jun Fu, Zhi Chen, Luquan Ren","doi":"10.13031/ja.15105","DOIUrl":"https://doi.org/10.13031/ja.15105","url":null,"abstract":"Highlights This study designed a corn ear picking device to reduce grain loss and corn header power consumption. The fracture force of corn peduncles under different deflection angles was studied as the basis of the design. The working parameters were optimized through an orthogonal experiment. Abstract. In corn ear picking, the corn peduncles are fractured under pure tensile forces. The large force demands in the fracture brought severe grain loss, an enormous instantaneous load, and high power consumption in the corn harvest. In this paper, the fracture behavior of the corn peduncles under different tensile orientations was studied. It showed the fracture force of corn peduncle could be reduced by more than 80% when its fracture mode transformed from tensile fracture to bending fracture as long as the corn ear was deflected to the critical angle of 55°. Based on this, a corn picking device was designed to reduce peduncle fracture force by deflecting corn ears to the critical angle. The optimal parameters of the designed corn picking device were determined as follows: the diameter of the snapping rollers was 20 mm, the rotating speed of the stalk rolls was 700 rpm, and the inclination angle of the corn picking unit was 28.3°. A comparative test between the designed corn picking device and a commonly used corn picking device was performed. It showed the designed corn picking device could reduce grain loss, average power consumption, and peak power. This study will provide a theoretical basis and design reference for corn harvester design to reduce grain loss and power consumption. Keywords: Corn ear picking, Corn harvest, Corn harvester header, Fracture force, Fracture mechanics, Grain loss, Power consumption.","PeriodicalId":29714,"journal":{"name":"Journal of the ASABE","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135600670","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yujie Wang, Donglin Zhuang, Jinghui Xu, Yeming Wang
{"title":"Soil Temperature Prediction Based on 1D-CNN-MLP Neural Network Model","authors":"Yujie Wang, Donglin Zhuang, Jinghui Xu, Yeming Wang","doi":"10.13031/ja.15354","DOIUrl":"https://doi.org/10.13031/ja.15354","url":null,"abstract":"","PeriodicalId":29714,"journal":{"name":"Journal of the ASABE","volume":"10 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89195029","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Camila Jange, Rhonda Graef, Chad Penn, Carl Wassgren, Kingsly Ambrose
Highlights Effect of granule microstructure, formulation design on nutrient leaching was investigated. Reduction in nutrient leaching was observed in denser core granules with binder compared to low density granules. The power-law model overpredicted the inorganic dissolved nitrogen content. Abstract. Ammonium and nitrate are byproducts of urea fertilizer hydrolysis in soil. Ammonium is highly unstable and can volatilize in the form of ammonia, a greenhouse gas. Meanwhile, nitrate is highly hydrophilic and can contaminate surface and groundwater systems. This study investigated the influence of a biopolymer binder (a mixture of xanthan and konjac gums) and granule microstructure on urea dissolution and hydrolysis in soil to improve fertilizer release rates. The study compared urea leaching profiles in disturbed soil columns for dry (uniaxial compression), layered wet granulated, and market urea granules. A power-law model of total dissolved nitrogen versus cumulative volume ensured robust estimation of the release rate constants. There was 50% and 20% less total dissolved nitrogen, respectively, for binder-added core (CB) granules produced from the uniaxial compression method and bilayer binder-added (bLB) granules compared with market urea samples (NU). However, no significant reduction in dissolved ammonium and nitrate was observed based on formulation and process changes using a power-law model. However, it is noteworthy that the power-law model overpredicted the initial leaching profiles of binder-added core (CB) and bilayer binder-added (bLB) samples. In conclusion, the microstructure of the core granules compacted at 100 MPa and binder-formulated (CB) granules can delay urea dissolution and suggests a partial reduction of urea hydrolysis in soil. Keywords: Biopolymer binder, Disturbed soil columns, Granule microstructure design, Nitrate leaching control.
{"title":"Controlling Nutrient Leaching Profile of Urea Granules through Structural Modification","authors":"Camila Jange, Rhonda Graef, Chad Penn, Carl Wassgren, Kingsly Ambrose","doi":"10.13031/ja.15675","DOIUrl":"https://doi.org/10.13031/ja.15675","url":null,"abstract":"Highlights Effect of granule microstructure, formulation design on nutrient leaching was investigated. Reduction in nutrient leaching was observed in denser core granules with binder compared to low density granules. The power-law model overpredicted the inorganic dissolved nitrogen content. Abstract. Ammonium and nitrate are byproducts of urea fertilizer hydrolysis in soil. Ammonium is highly unstable and can volatilize in the form of ammonia, a greenhouse gas. Meanwhile, nitrate is highly hydrophilic and can contaminate surface and groundwater systems. This study investigated the influence of a biopolymer binder (a mixture of xanthan and konjac gums) and granule microstructure on urea dissolution and hydrolysis in soil to improve fertilizer release rates. The study compared urea leaching profiles in disturbed soil columns for dry (uniaxial compression), layered wet granulated, and market urea granules. A power-law model of total dissolved nitrogen versus cumulative volume ensured robust estimation of the release rate constants. There was 50% and 20% less total dissolved nitrogen, respectively, for binder-added core (CB) granules produced from the uniaxial compression method and bilayer binder-added (bLB) granules compared with market urea samples (NU). However, no significant reduction in dissolved ammonium and nitrate was observed based on formulation and process changes using a power-law model. However, it is noteworthy that the power-law model overpredicted the initial leaching profiles of binder-added core (CB) and bilayer binder-added (bLB) samples. In conclusion, the microstructure of the core granules compacted at 100 MPa and binder-formulated (CB) granules can delay urea dissolution and suggests a partial reduction of urea hydrolysis in soil. Keywords: Biopolymer binder, Disturbed soil columns, Granule microstructure design, Nitrate leaching control.","PeriodicalId":29714,"journal":{"name":"Journal of the ASABE","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135710164","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Marlene C. Ndoun, Allan Knopf, Heather E. Preisendanz, Natasha Vozenilek, Herschel A. Elliott, Tamie L. Veith, Michael L. Mashtare, Stephanie B. Velegol, Clinton F. Williams
Highlights Cotton gin waste and walnut shells can be beneficially transformed into alkaline biochars. The resulting biochars have properties supporting effective adsorption of cationic contaminants. The biochars exhibit irregular particle morphologies, with cotton gin biochar maintaining fibrous structures. Results can help inform appropriate applications of biochar produced from cotton gin waste and walnut shells. Abstract. The sustainable management of agricultural waste has gained increasing attention worldwide, especially regarding the production of value-added products that are renewable and carbon-rich. Further, there is a need to provide low-cost, lower-energy alternatives to materials such as activated carbon for removing contaminants from water. The goal of this study was to characterize various physicochemical properties of biochar produced from cotton gin waste (pyrolyzed for 2 h at 700ï°C, CG700) and walnut shells (pyrolyzed for 2 h at 800ï°C, WS800) to better understand their potential to be effective in various environmental applications. The properties that were characterized are the following: (i) biochar pH; (ii) specific surface area (SSA); (iii) surface functional groups; (iv) surface elemental composition; (v) surface charge; and (vi) surface morphology. Pyrolysis led to the destruction of acidic functional groups within the parent biomass and an increase in ash content, resulting in alkaline biochars with pH values of 9.8 and 10.9 for WS800 and CG700 biochar, respectively. Zeta potential measurements demonstrated that both biochars were negatively charged at environmentally relevant pH ranges. The FT-IR spectrum and XPS results for the CG700 biochar showed the presence of several functional groups, including the OH, C=C, and C-O groups within the biochar samples. BET results demonstrated that CG700 had a low SSA (8.57â22.31 m2 g-1), and the biochar was dominated by fibrous, irregular shaped particles, according to the results from the SEM imaging. The FT-IR spectrum for the WS800 biochar showed the presence of the carbonyl group, which was inherited from the parent biomass. BET measurements for the WS800 showed a decline in SSA with a reduction in particle size, likely due to a collapse of the honeycomb structure of the WS800 biochar with crushing to reduce the particle size, as revealed by the SEM images. The results of this research will help to inform the applications of biochar produced from cotton gin waste and walnut shells, two large sources of agricultural waste materials, and promote sustainable alternatives to extend the life cycle of these materials into value-added products.
{"title":"Physicochemical Characterization of Biochar Derived From the Pyrolysis of Cotton Gin Waste and Walnut Shells","authors":"Marlene C. Ndoun, Allan Knopf, Heather E. Preisendanz, Natasha Vozenilek, Herschel A. Elliott, Tamie L. Veith, Michael L. Mashtare, Stephanie B. Velegol, Clinton F. Williams","doi":"10.13031/ja.15489","DOIUrl":"https://doi.org/10.13031/ja.15489","url":null,"abstract":"<b>Highlights</b> <list list-type=bullet><list-item> Cotton gin waste and walnut shells can be beneficially transformed into alkaline biochars. </list-item><list-item> The resulting biochars have properties supporting effective adsorption of cationic contaminants. </list-item><list-item> The biochars exhibit irregular particle morphologies, with cotton gin biochar maintaining fibrous structures. </list-item><list-item> Results can help inform appropriate applications of biochar produced from cotton gin waste and walnut shells. </list-item></list> <b>Abstract.</b> The sustainable management of agricultural waste has gained increasing attention worldwide, especially regarding the production of value-added products that are renewable and carbon-rich. Further, there is a need to provide low-cost, lower-energy alternatives to materials such as activated carbon for removing contaminants from water. The goal of this study was to characterize various physicochemical properties of biochar produced from cotton gin waste (pyrolyzed for 2 h at 700ï°C, CG700) and walnut shells (pyrolyzed for 2 h at 800ï°C, WS800) to better understand their potential to be effective in various environmental applications. The properties that were characterized are the following: (i) biochar pH; (ii) specific surface area (SSA); (iii) surface functional groups; (iv) surface elemental composition; (v) surface charge; and (vi) surface morphology. Pyrolysis led to the destruction of acidic functional groups within the parent biomass and an increase in ash content, resulting in alkaline biochars with pH values of 9.8 and 10.9 for WS800 and CG700 biochar, respectively. Zeta potential measurements demonstrated that both biochars were negatively charged at environmentally relevant pH ranges. The FT-IR spectrum and XPS results for the CG700 biochar showed the presence of several functional groups, including the OH, C=C, and C-O groups within the biochar samples. BET results demonstrated that CG700 had a low SSA (8.57â22.31 m2 g-1), and the biochar was dominated by fibrous, irregular shaped particles, according to the results from the SEM imaging. The FT-IR spectrum for the WS800 biochar showed the presence of the carbonyl group, which was inherited from the parent biomass. BET measurements for the WS800 showed a decline in SSA with a reduction in particle size, likely due to a collapse of the honeycomb structure of the WS800 biochar with crushing to reduce the particle size, as revealed by the SEM images. The results of this research will help to inform the applications of biochar produced from cotton gin waste and walnut shells, two large sources of agricultural waste materials, and promote sustainable alternatives to extend the life cycle of these materials into value-added products.","PeriodicalId":29714,"journal":{"name":"Journal of the ASABE","volume":"113 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136003565","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Silvia Eugenia Flores, A. M. Leon, Betsabe Leon, Rosario Ysabel Bravo, W. Medina
HIGHLIGHTS Grains of three cañihua cultivars were identified through the determination of fractal dimension of its force?deformation curves. A special test cell device was developed to mechanically assess small grains during compression tests. Cañihua cultivars form separate groups when results of fractal dimension of their force?deformation curves, force of rupture, and fracture force are analyzed with PCA. ABSTRACT.Cañihua is an ancient crop of the Andean regions in South America. High genetic diversity of this crop can be found around Lake Titicaca. Cañihua grain is an important source of food for the people in this region because of its high protein and amino acid contents. Currently, there are three known cultivars and more than a hundred accessions of cañihua. Most of the grains from these cultivars and accessions have the same shape and color, making their identification difficult. This work sought to estimate the fractal dimension of force–deformation curves obtained during individual cañihua grain compression tests through the box-counting method (BCM) and the Higuchi fractal dimension (HFD) to show the possibility of differentiating and recognizing cañihua cultivars by taking into consideration the influence of their mechanical properties and chemical composition. Using BCM for the fractal dimension of the force-strain curves allowed us to differentiate the three cultivars from each other, and with HFD, it was possible to observe the difference between accessions and cultivars. Finally, by using the BCM and HFD results, together with mechanical properties such as the bioyield and rupture points and the energy required to reach them, the three cañihua cultivars could be differentiated from the accessions through multivariate PCA. The findings of this work could be applied to distinguish or identify cultivars of different crop grains. Keywords: Cañihua cultivars and accessions, Fractal dimension, Force–deformation curves, PCA.
{"title":"Application of Uniaxial Compression Curve Fractal Dimension in the Identification of Cañihua (Chenopodium Pallidicaule Aellen) Grain Cultivars","authors":"Silvia Eugenia Flores, A. M. Leon, Betsabe Leon, Rosario Ysabel Bravo, W. Medina","doi":"10.13031/ja.15277","DOIUrl":"https://doi.org/10.13031/ja.15277","url":null,"abstract":"HIGHLIGHTS Grains of three cañihua cultivars were identified through the determination of fractal dimension of its force?deformation curves. A special test cell device was developed to mechanically assess small grains during compression tests. Cañihua cultivars form separate groups when results of fractal dimension of their force?deformation curves, force of rupture, and fracture force are analyzed with PCA. ABSTRACT.Cañihua is an ancient crop of the Andean regions in South America. High genetic diversity of this crop can be found around Lake Titicaca. Cañihua grain is an important source of food for the people in this region because of its high protein and amino acid contents. Currently, there are three known cultivars and more than a hundred accessions of cañihua. Most of the grains from these cultivars and accessions have the same shape and color, making their identification difficult. This work sought to estimate the fractal dimension of force–deformation curves obtained during individual cañihua grain compression tests through the box-counting method (BCM) and the Higuchi fractal dimension (HFD) to show the possibility of differentiating and recognizing cañihua cultivars by taking into consideration the influence of their mechanical properties and chemical composition. Using BCM for the fractal dimension of the force-strain curves allowed us to differentiate the three cultivars from each other, and with HFD, it was possible to observe the difference between accessions and cultivars. Finally, by using the BCM and HFD results, together with mechanical properties such as the bioyield and rupture points and the energy required to reach them, the three cañihua cultivars could be differentiated from the accessions through multivariate PCA. The findings of this work could be applied to distinguish or identify cultivars of different crop grains. Keywords: Cañihua cultivars and accessions, Fractal dimension, Force–deformation curves, PCA.","PeriodicalId":29714,"journal":{"name":"Journal of the ASABE","volume":"23 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72750616","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Highlights This study analyzes the feasibility of using Artificial Neural Networks (ANNs) to estimate canopy temperatures. A methodology is introduced to forecast canopy temperatures using historical canopy temperatures. ANNs can predict canopy temperatures with satisfactory accuracy for plant stress-based irrigation scheduling. The methodology can be useful to add redundancy to plant stress-based irrigation scheduling methods. Abstract. Recent advances can provide farmers with irrigation scheduling tools based on crop stress indicators to assist in the management of Variable Rate Irrigation (VRI) center pivot systems. These tools were integrated into an Irrigation Scheduling Supervisory Control and Data Acquisition System (ISSCADAS) developed by scientists with the USDA-Agricultural Research Service (ARS). The ISSCADAS automates the collection of data from a network of wireless infrared thermometers (IRTs) distributed on a center pivot’s lateral and in the field irrigated by the center pivot, as well as data from a wireless soil water sensor network and a microclimate weather station. This study analyzes the use of Artificial Neural Networks (ANNs), a type of machine learning algorithm, for the forecasting of canopy temperatures obtained by a wireless network of IRTs mounted on a three-span VRI center pivot irrigating corn near Bushland, TX, during the summer of 2017. Among the predictors used by the ANNs were weather variables relevant to the estimation of evapotranspiration (i.e., air temperature, relative humidity, solar irradiance, and wind speed), irrigation management variables (irrigation treatment, irrigation scheduling method, and the amount of water received during the last 5 days as irrigation or rainfall), and days after planting. Two case studies were conducted using data collected from periodic scans of the field performed during the growing season by running the pivot dry. In the first case, data from the first three scans were used to train an ANN, and canopy temperatures estimated using the ANN were then compared against canopy temperatures measured by the network of IRTs during the fourth scan. In the second case, data from the first six scans were used to train ANNs, and canopy temperatures estimated using the ANN were then compared against canopy temperatures measured by the network of IRTs during the seventh scan. The Root of the Mean Squared Error (RMSE) of ANN predictions in the first case ranged from 1.04°C to 2.49°C, whereas the RMSE of ANN predictions in the second case ranged from 2.14°C to 2.77°C. To assess the impact of ANN accuracy on irrigation management, estimated canopy temperatures were fed to a plant-stress-based irrigation scheduling method, and the resulting prescription maps were compared against prescription maps obtained by the same method using the canopy temperatures measured by the network of IRTs. In the first case, no difference was found between both prescription map
{"title":"Forecasting of Canopy Temperatures Using Machine Learning Algorithms","authors":"M. Andrade, S. O'Shaughnessy, S. Evett","doi":"10.13031/ja.15213","DOIUrl":"https://doi.org/10.13031/ja.15213","url":null,"abstract":"Highlights This study analyzes the feasibility of using Artificial Neural Networks (ANNs) to estimate canopy temperatures. A methodology is introduced to forecast canopy temperatures using historical canopy temperatures. ANNs can predict canopy temperatures with satisfactory accuracy for plant stress-based irrigation scheduling. The methodology can be useful to add redundancy to plant stress-based irrigation scheduling methods. Abstract. Recent advances can provide farmers with irrigation scheduling tools based on crop stress indicators to assist in the management of Variable Rate Irrigation (VRI) center pivot systems. These tools were integrated into an Irrigation Scheduling Supervisory Control and Data Acquisition System (ISSCADAS) developed by scientists with the USDA-Agricultural Research Service (ARS). The ISSCADAS automates the collection of data from a network of wireless infrared thermometers (IRTs) distributed on a center pivot’s lateral and in the field irrigated by the center pivot, as well as data from a wireless soil water sensor network and a microclimate weather station. This study analyzes the use of Artificial Neural Networks (ANNs), a type of machine learning algorithm, for the forecasting of canopy temperatures obtained by a wireless network of IRTs mounted on a three-span VRI center pivot irrigating corn near Bushland, TX, during the summer of 2017. Among the predictors used by the ANNs were weather variables relevant to the estimation of evapotranspiration (i.e., air temperature, relative humidity, solar irradiance, and wind speed), irrigation management variables (irrigation treatment, irrigation scheduling method, and the amount of water received during the last 5 days as irrigation or rainfall), and days after planting. Two case studies were conducted using data collected from periodic scans of the field performed during the growing season by running the pivot dry. In the first case, data from the first three scans were used to train an ANN, and canopy temperatures estimated using the ANN were then compared against canopy temperatures measured by the network of IRTs during the fourth scan. In the second case, data from the first six scans were used to train ANNs, and canopy temperatures estimated using the ANN were then compared against canopy temperatures measured by the network of IRTs during the seventh scan. The Root of the Mean Squared Error (RMSE) of ANN predictions in the first case ranged from 1.04°C to 2.49°C, whereas the RMSE of ANN predictions in the second case ranged from 2.14°C to 2.77°C. To assess the impact of ANN accuracy on irrigation management, estimated canopy temperatures were fed to a plant-stress-based irrigation scheduling method, and the resulting prescription maps were compared against prescription maps obtained by the same method using the canopy temperatures measured by the network of IRTs. In the first case, no difference was found between both prescription map","PeriodicalId":29714,"journal":{"name":"Journal of the ASABE","volume":"342 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79560478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
HIGHLIGHTS A CFD model was developed to simulate airflow movements from circulating air-assisted sprayer. The CFD model can simulate airflow distribution inside the pear canopy with good accuracy. Simulation identifies the preferred parameters for circulating air-assisted spraying. An excessive adjustment of the airflow angle resulted in the formation of an eddy. ABSTRACT. Circulating air-assisted (CAA) spraying involves a negative pressure suction (NPS) created by a fan placed over the top of a canopy to change the airflow direction twice, i.e., first from the outside of the canopy to its inside and then from the bottom up, which can increase the airflow velocity inside the canopy. However, this new pesticide application technology has not been adequately investigated. In particular, the effects of the inlet and outlet airflow parameters of CAA spraying technology on the airflow distribution inside a canopy are yet to be determined. In this study, a computational fluid dynamics (CFD) model is developed and validated to simulate the interactions between the airflow ejected by a CAA sprayer and the canopy of a fruit tree. In the computational domain, the fruit tree is considered a porous medium. The model is validated based on three fruit trees of different sizes, leaf-area densities (LAD). The root mean square error and the mean relative square error are 1.44, 1.43, 2.22 m/s, and 24.9%, 24.7%, and 36.4%, respectively. This suggests that the CFD model can predict the interactions between the airflow field generated by a CAA sprayer and the canopy of a fruit tree. The validated CFD model is employed to analyze the airflow distribution patterns inside a canopy under different combinations of inlet and outlet airflow parameters. A reasonable combination of inlet and airflow parameters is obtained for CAA spraying technology. For example, the suitable outlet airflow velocity, top NPS, and bottom outlet angle for seven-year-old crown pear trees (average height: 2.0 m; average canopy diameter: 1.2 m; average trunk height: 0.62 m; average LAD: 2.96) selected in this study from a farm in southern China are 15 m/s, 200 Pa, and 10°, respectively. The results of this study can facilitate the parametric adjustment of CAA sprayers and enhance plant protection in orchards. Keywords: Circulating air-assisted spraying, Fruit-tree canopy, Inlet and outlet airflow parameters, Simulation.
{"title":"CFD Simulation of Circulating-Airflow Distribution Inside Canopy From Novel Air-Assisted Sprayer in Orchard","authors":"Hao Sun, He Zheng, Hongfeng Yu, Wei Qiu, Yubin Cao, Xiaolan Lv, Zhengwei Zhang","doi":"10.13031/ja.15483","DOIUrl":"https://doi.org/10.13031/ja.15483","url":null,"abstract":"HIGHLIGHTS A CFD model was developed to simulate airflow movements from circulating air-assisted sprayer. The CFD model can simulate airflow distribution inside the pear canopy with good accuracy. Simulation identifies the preferred parameters for circulating air-assisted spraying. An excessive adjustment of the airflow angle resulted in the formation of an eddy. ABSTRACT. Circulating air-assisted (CAA) spraying involves a negative pressure suction (NPS) created by a fan placed over the top of a canopy to change the airflow direction twice, i.e., first from the outside of the canopy to its inside and then from the bottom up, which can increase the airflow velocity inside the canopy. However, this new pesticide application technology has not been adequately investigated. In particular, the effects of the inlet and outlet airflow parameters of CAA spraying technology on the airflow distribution inside a canopy are yet to be determined. In this study, a computational fluid dynamics (CFD) model is developed and validated to simulate the interactions between the airflow ejected by a CAA sprayer and the canopy of a fruit tree. In the computational domain, the fruit tree is considered a porous medium. The model is validated based on three fruit trees of different sizes, leaf-area densities (LAD). The root mean square error and the mean relative square error are 1.44, 1.43, 2.22 m/s, and 24.9%, 24.7%, and 36.4%, respectively. This suggests that the CFD model can predict the interactions between the airflow field generated by a CAA sprayer and the canopy of a fruit tree. The validated CFD model is employed to analyze the airflow distribution patterns inside a canopy under different combinations of inlet and outlet airflow parameters. A reasonable combination of inlet and airflow parameters is obtained for CAA spraying technology. For example, the suitable outlet airflow velocity, top NPS, and bottom outlet angle for seven-year-old crown pear trees (average height: 2.0 m; average canopy diameter: 1.2 m; average trunk height: 0.62 m; average LAD: 2.96) selected in this study from a farm in southern China are 15 m/s, 200 Pa, and 10°, respectively. The results of this study can facilitate the parametric adjustment of CAA sprayers and enhance plant protection in orchards. Keywords: Circulating air-assisted spraying, Fruit-tree canopy, Inlet and outlet airflow parameters, Simulation.","PeriodicalId":29714,"journal":{"name":"Journal of the ASABE","volume":"142 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76199791","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Highlights More diverted flow to the buffer does not necessarily mean more nitrate load removal. A design approach should incorporate a nitrate removal component to maximize nitrate load removal. The newly proposed design follows a process-based approach to estimate the annual site-specific nitrate removal. The newly proposed design provided more consistent nitrate load removal regardless of the site conditions. Neglecting exit head loss in the design process leads to an overestimation of diverted flow and nitrate load removal. Abstract. A saturated buffer (SB) is a conservation drainage practice that removes nitrate from subsurface drainage discharge. The reported wide range of nitrate load removal necessitates improvements in design approaches for more consistent performance. There are two SB design approaches: Illinois Natural Resources Conservation Service (Design 1) and McEachran et al. (2020) (Design 2). We proposed a new Design 3 that builds on the previous two designs. In Design 3, the nitrate load removal was simulated for buffer widths ranging from 3 to 30 m with a 0.3-m interval, and the buffer width that maximized the annual nitrate load reduction over the long term was chosen as the SB design. The objective of this study was to identify the best design approaches for maximizing nitrate load removal based on field data. Daily drainage discharge data from two field sites in Michigan were used to design a hypothetical SB length and width for each approach. The designs were compared by applying an identical method to estimate the nitrate load removal for each hypothetical SB system. The method extends Designs 1 and 2 by incorporating a hydrological and nitrate removal component. The results showed that using the minimum recommended buffer width of 9.1 m and the minimum 5% SB design capacity of Design 1 resulted in 25% to 35% of diverted flow to the buffer and 14% to 16% nitrate load removal at the two field sites. However, Design 1 resulted in the lowest nitrate removal compared to Designs 2 and 3 (i.e., 0.3% to 3.4% lower). Designs 2 and 3 consistently provided maximum nitrate load removal regardless of the site conditions, whereas the performance of Design 1 was inconsistent. In conclusion, Designs 2 and 3 were equally good and resulted in higher nitrate load removal compared to Design 1. Keywords: Conservation practice, Exit head loss, Nitrate, Subsurface drainage, Tile drainage, Water quality.
{"title":"Comparison of Newly Proposed and Existing Design Approach for Saturated Buffers","authors":"Yousef Abdalaal, E. Ghane","doi":"10.13031/ja.15246","DOIUrl":"https://doi.org/10.13031/ja.15246","url":null,"abstract":"Highlights More diverted flow to the buffer does not necessarily mean more nitrate load removal. A design approach should incorporate a nitrate removal component to maximize nitrate load removal. The newly proposed design follows a process-based approach to estimate the annual site-specific nitrate removal. The newly proposed design provided more consistent nitrate load removal regardless of the site conditions. Neglecting exit head loss in the design process leads to an overestimation of diverted flow and nitrate load removal. Abstract. A saturated buffer (SB) is a conservation drainage practice that removes nitrate from subsurface drainage discharge. The reported wide range of nitrate load removal necessitates improvements in design approaches for more consistent performance. There are two SB design approaches: Illinois Natural Resources Conservation Service (Design 1) and McEachran et al. (2020) (Design 2). We proposed a new Design 3 that builds on the previous two designs. In Design 3, the nitrate load removal was simulated for buffer widths ranging from 3 to 30 m with a 0.3-m interval, and the buffer width that maximized the annual nitrate load reduction over the long term was chosen as the SB design. The objective of this study was to identify the best design approaches for maximizing nitrate load removal based on field data. Daily drainage discharge data from two field sites in Michigan were used to design a hypothetical SB length and width for each approach. The designs were compared by applying an identical method to estimate the nitrate load removal for each hypothetical SB system. The method extends Designs 1 and 2 by incorporating a hydrological and nitrate removal component. The results showed that using the minimum recommended buffer width of 9.1 m and the minimum 5% SB design capacity of Design 1 resulted in 25% to 35% of diverted flow to the buffer and 14% to 16% nitrate load removal at the two field sites. However, Design 1 resulted in the lowest nitrate removal compared to Designs 2 and 3 (i.e., 0.3% to 3.4% lower). Designs 2 and 3 consistently provided maximum nitrate load removal regardless of the site conditions, whereas the performance of Design 1 was inconsistent. In conclusion, Designs 2 and 3 were equally good and resulted in higher nitrate load removal compared to Design 1. Keywords: Conservation practice, Exit head loss, Nitrate, Subsurface drainage, Tile drainage, Water quality.","PeriodicalId":29714,"journal":{"name":"Journal of the ASABE","volume":"362 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76423002","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Te Xi, Huaiqu Feng, Yongwei Wang, D. Yang, Dong-Lin Li, Fuqiang Yao, Jun Wang
Highlights An experimental platform for the kinematic characteristics of panicles was constructed. A regression model for the kinematic characteristics of panicles and working parameters was established. The multi-objective optimization based on the kinematic characteristics of rice panicles was carried out. The optimized combination of working parameters was verified by field pollination experiments. Abstract. Pollen shedding and dispersal processes are inextricably linked to the movement state of hybrid rice panicles. The purpose of this work was to study the effect of the working parameters of the pneumatic pollinator on the kinematic characteristics of hybrid rice panicles during flowering and to further optimize the working parameters of the pollinator. An experimental platform was built to characterize the movement of the panicle. Orthogonal experiments were conducted with airflow velocity, action position, and walking speed as experimental factors and kinematic parameters such as displacement, velocity, and acceleration of the rice panicle as experimental indicators. A quadratic regression model between the working parameters and the motion characteristics of the rice panicle was constructed and analyzed by analysis of variance (ANOVA). Matrix analysis was used for multi-objective optimization of the working parameter combinations. Field pollination trials were conducted for the optimized combination of parameters. The results showed that the coefficients of determination of the regression models were all above 0.85, which indicated good accuracy. The motion characteristics of the panicle, including the displacement maximum, velocity maximum, and acceleration maximum, can be maintained at a high level when the airflow velocity is 24 m/s, the action position is 120 mm from the top of the panicle, and the walking speed is 0.4 m/s. The field experiments showed that the optimization results could obtain the desired pollen density, distribution, and uniformity. This study can serve as a reference for the development of pneumatic hybrid rice pollination theory and the optimal design of the pollinator structure. Keywords: Hybrid rice seed production, Kinematic characteristics, Mechanized pollination, Multi-objective optimization.
{"title":"Optimizing the Working Parameters of Pneumatic Pollinators Based on the Kinematic Properties of Rice Panicles","authors":"Te Xi, Huaiqu Feng, Yongwei Wang, D. Yang, Dong-Lin Li, Fuqiang Yao, Jun Wang","doi":"10.13031/ja.15308","DOIUrl":"https://doi.org/10.13031/ja.15308","url":null,"abstract":"Highlights An experimental platform for the kinematic characteristics of panicles was constructed. A regression model for the kinematic characteristics of panicles and working parameters was established. The multi-objective optimization based on the kinematic characteristics of rice panicles was carried out. The optimized combination of working parameters was verified by field pollination experiments. Abstract. Pollen shedding and dispersal processes are inextricably linked to the movement state of hybrid rice panicles. The purpose of this work was to study the effect of the working parameters of the pneumatic pollinator on the kinematic characteristics of hybrid rice panicles during flowering and to further optimize the working parameters of the pollinator. An experimental platform was built to characterize the movement of the panicle. Orthogonal experiments were conducted with airflow velocity, action position, and walking speed as experimental factors and kinematic parameters such as displacement, velocity, and acceleration of the rice panicle as experimental indicators. A quadratic regression model between the working parameters and the motion characteristics of the rice panicle was constructed and analyzed by analysis of variance (ANOVA). Matrix analysis was used for multi-objective optimization of the working parameter combinations. Field pollination trials were conducted for the optimized combination of parameters. The results showed that the coefficients of determination of the regression models were all above 0.85, which indicated good accuracy. The motion characteristics of the panicle, including the displacement maximum, velocity maximum, and acceleration maximum, can be maintained at a high level when the airflow velocity is 24 m/s, the action position is 120 mm from the top of the panicle, and the walking speed is 0.4 m/s. The field experiments showed that the optimization results could obtain the desired pollen density, distribution, and uniformity. This study can serve as a reference for the development of pneumatic hybrid rice pollination theory and the optimal design of the pollinator structure. Keywords: Hybrid rice seed production, Kinematic characteristics, Mechanized pollination, Multi-objective optimization.","PeriodicalId":29714,"journal":{"name":"Journal of the ASABE","volume":"25 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87089736","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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