Pub Date : 2023-01-01DOI: 10.25165/j.ijabe.20231603.7455
Dong Dai, Du Chen, Xu Mao, Yawei Zhang, Yutong Li, Shumao Wang, Bin Zhang
The real-time monitoring of the load in farming by the sensor installed on the tractor's three-point hitch can effectively improve the farming efficiency and force-position combined control, reduce the compaction risk of the wheel on the soil and reduce the fuel consumption in farming process. However, the measurement and quantification of the loads on the three-point hitch have some problems remaining unresolved: testing the accuracy and reliability of a load measuring system is hard when the tractor works in a field, the mathematical model of spatial forces usually lacks a practical and effective validation, and the calibration process of the measurement system is inconvenient and incomplete while easily causing a low accuracy. Specifically, this paper builds a new spatial-force mathematical model based on the geometry of a three-point hitch. To eliminate the discrepancy of the geometric model with the actual structure and to refine the mathematical model, a calibration process is conducted by developing a calibration bench, which is equipped with a data acquisition system and a multi-parameter monitoring interface. The three-point hitch installed on this calibration bench is subject to steady-state loading. The loading force, angle of the lower drawbar, and three-component forces (three shaft pin sensors’ forces) of the three-point hitch are well measured. With applying for the measured data to calibrate the theoretical mathematic model eventually derives the resultant force from all the three-component forces, a dynamical loading bench was developed to test the calculated resultant force for the three-point hitch during the sinusoidal and randomly variant dynamical loadings tests. A hitch force measurement system is also developed to collect real-time data and calculate the resultant force of measured three-component forces through the calibrated mathematical model. The results of the dynamical loading tests show that the average relative error MRE=1.09% with an average force measurement time delay being Δt=0.5 s, the root mean square error RMSE=59.3 N, and the coefficient of determination R2=0.9903. As observed, the shape and the trend of the generated resultant force curve are basically the dynamical loading force. The dynamical loading test proves the high efficacy and reliability of the proposed indoor calibration method for calculating the load based on the three-component forces as measured on the three-point hitch. Besides, the preliminary study of the proposed method on the hitch load provides great potential to improve the indoor six-component measurement and quantification of both the force and momentum acting on the three-point hitch. Keywords: tractor, three-point hitch, hitch force calibration bench, hitch force measurement system, dynamic loading verification method DOI: 10.25165/j.ijabe.20231603.7455 Citation: Dai D, Chen D, Mao X, Zhang Y W, Li Y T, Wang S M, et al. Design and performance analysis of indoor calibration device
{"title":"Design and performance analysis of indoor calibration device for the force-measuring system of the tractor three-point hitch","authors":"Dong Dai, Du Chen, Xu Mao, Yawei Zhang, Yutong Li, Shumao Wang, Bin Zhang","doi":"10.25165/j.ijabe.20231603.7455","DOIUrl":"https://doi.org/10.25165/j.ijabe.20231603.7455","url":null,"abstract":"The real-time monitoring of the load in farming by the sensor installed on the tractor's three-point hitch can effectively improve the farming efficiency and force-position combined control, reduce the compaction risk of the wheel on the soil and reduce the fuel consumption in farming process. However, the measurement and quantification of the loads on the three-point hitch have some problems remaining unresolved: testing the accuracy and reliability of a load measuring system is hard when the tractor works in a field, the mathematical model of spatial forces usually lacks a practical and effective validation, and the calibration process of the measurement system is inconvenient and incomplete while easily causing a low accuracy. Specifically, this paper builds a new spatial-force mathematical model based on the geometry of a three-point hitch. To eliminate the discrepancy of the geometric model with the actual structure and to refine the mathematical model, a calibration process is conducted by developing a calibration bench, which is equipped with a data acquisition system and a multi-parameter monitoring interface. The three-point hitch installed on this calibration bench is subject to steady-state loading. The loading force, angle of the lower drawbar, and three-component forces (three shaft pin sensors’ forces) of the three-point hitch are well measured. With applying for the measured data to calibrate the theoretical mathematic model eventually derives the resultant force from all the three-component forces, a dynamical loading bench was developed to test the calculated resultant force for the three-point hitch during the sinusoidal and randomly variant dynamical loadings tests. A hitch force measurement system is also developed to collect real-time data and calculate the resultant force of measured three-component forces through the calibrated mathematical model. The results of the dynamical loading tests show that the average relative error MRE=1.09% with an average force measurement time delay being Δt=0.5 s, the root mean square error RMSE=59.3 N, and the coefficient of determination R2=0.9903. As observed, the shape and the trend of the generated resultant force curve are basically the dynamical loading force. The dynamical loading test proves the high efficacy and reliability of the proposed indoor calibration method for calculating the load based on the three-component forces as measured on the three-point hitch. Besides, the preliminary study of the proposed method on the hitch load provides great potential to improve the indoor six-component measurement and quantification of both the force and momentum acting on the three-point hitch. Keywords: tractor, three-point hitch, hitch force calibration bench, hitch force measurement system, dynamic loading verification method DOI: 10.25165/j.ijabe.20231603.7455 Citation: Dai D, Chen D, Mao X, Zhang Y W, Li Y T, Wang S M, et al. Design and performance analysis of indoor calibration device ","PeriodicalId":13895,"journal":{"name":"International Journal of Agricultural and Biological Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135357312","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Kinematic synthesis and simulation of a vegetable pot seedling transplanting mechanism with four exact task poses","authors":"Liang Sun, Haoming Xu, Yuzhu Zhou, Jiahao Shen, Gaohong Yu, Huafeng Hu, Yuejun Miao","doi":"10.25165/j.ijabe.20231602.6739","DOIUrl":"https://doi.org/10.25165/j.ijabe.20231602.6739","url":null,"abstract":"","PeriodicalId":13895,"journal":{"name":"International Journal of Agricultural and Biological Engineering","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88468151","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.25165/j.ijabe.20231602.5931
A. Numsong, J. Posom, S. Chuan-udom
: This research proposes an artificial neural network (ANN)-based repair and maintenance (R&M) cost estimation model for agricultural machinery. The proposed ANN model can achieve high estimation accuracy with small data requirement. In the study, the proposed ANN model is implemented to estimate the R&M costs using a sample of locally-made rice combine harvesters. The model inputs are geographical regions, harvest area, and curve fitting coefficients related to historical cost data; and the ANN output is the estimated R&M cost. Multilayer feed-forward is adopted as the processing algorithm and Levenberg-Marquardt backpropagation learning as the training algorithm. The R&M costs are estimated using the ANN-based model, and results are compared with those of conventional mathematical estimation model. The results reveal that the percentage error between the conventional and ANN-based estimation models is below 1%, indicating the proposed ANN model’s high predictive accuracy. The proposed ANN-based model is useful for setting the service rates of agricultural machinery, given the significance of R&M cost in profitability. The novelty of this research lies in the use of curve-fitting coefficients in the ANN-based estimation model to improve estimation accuracy. Besides, the proposed ANN model could be further developed into web-based applications using a programming language to enable ease of use and greater user accessibility. Moreover, with minor modifications, the ANN estimation model is also applicable to other geographical areas and tractors or combine harvesters of different countries of origin.
{"title":"Artificial neural network-based repair and maintenance cost estimation model for rice combine harvesters","authors":"A. Numsong, J. Posom, S. Chuan-udom","doi":"10.25165/j.ijabe.20231602.5931","DOIUrl":"https://doi.org/10.25165/j.ijabe.20231602.5931","url":null,"abstract":": This research proposes an artificial neural network (ANN)-based repair and maintenance (R&M) cost estimation model for agricultural machinery. The proposed ANN model can achieve high estimation accuracy with small data requirement. In the study, the proposed ANN model is implemented to estimate the R&M costs using a sample of locally-made rice combine harvesters. The model inputs are geographical regions, harvest area, and curve fitting coefficients related to historical cost data; and the ANN output is the estimated R&M cost. Multilayer feed-forward is adopted as the processing algorithm and Levenberg-Marquardt backpropagation learning as the training algorithm. The R&M costs are estimated using the ANN-based model, and results are compared with those of conventional mathematical estimation model. The results reveal that the percentage error between the conventional and ANN-based estimation models is below 1%, indicating the proposed ANN model’s high predictive accuracy. The proposed ANN-based model is useful for setting the service rates of agricultural machinery, given the significance of R&M cost in profitability. The novelty of this research lies in the use of curve-fitting coefficients in the ANN-based estimation model to improve estimation accuracy. Besides, the proposed ANN model could be further developed into web-based applications using a programming language to enable ease of use and greater user accessibility. Moreover, with minor modifications, the ANN estimation model is also applicable to other geographical areas and tractors or combine harvesters of different countries of origin.","PeriodicalId":13895,"journal":{"name":"International Journal of Agricultural and Biological Engineering","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86339653","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.25165/j.ijabe.20231602.7216
S. Fu, Jin-Quan Lu, I. Walder, Daishe Wu
: The leaching of heavy metals from tailings deposit due to the oxidation of sulphidic tailings and formation of acidic leachate is considered a high risk to the surrounding environment. Temperature plays an important role in the leaching of heavy metals from tailings in changing acid-based environment, especially in the Arctic area. To investigate how the temperature variation affected metal release from tailings in the Arctic area, a series of column leaching experiments was conducted under four temperature situations (5°C, 10°C, 14°C and 18°C). Physicochemical properties, Fe, Zn, Ni and Mn concentrations of leachates at each cycle were measured, and multivariate statistical analysis was applied to research the effect of temperature on heavy metals leaching from tailings in the Arctic area. The results showed that higher temperatures encouraged tailings to oxidation and sulfuration of and promoted heavy metal release from the tailings through precipitation and erosion. Ni, Zn and Mn have similar releasing resources from tailings and positive correlation in the leaching activity. Rising temperature accelerated Fe leaching; Fe leaching promoted leaching of the other metals, especially of Mn. Appropriately increase temperature will accelerate oxidization and sulfidization of the tailings, promote acid generation and increase TDS and, finally, promote the release of heavy metals. Climate change, with rising temperatures increasing the risk of heavy metals leaching from the tailings, should be given greater attention. Keeping tailings away from the appropriate temperature and in a higher alkalinity is a good method to control the leaching of heavy metals from tailings.
{"title":"Effect of temperature on the leaching of heavy metals from nickel mine tailings in the arctic area, Norway","authors":"S. Fu, Jin-Quan Lu, I. Walder, Daishe Wu","doi":"10.25165/j.ijabe.20231602.7216","DOIUrl":"https://doi.org/10.25165/j.ijabe.20231602.7216","url":null,"abstract":": The leaching of heavy metals from tailings deposit due to the oxidation of sulphidic tailings and formation of acidic leachate is considered a high risk to the surrounding environment. Temperature plays an important role in the leaching of heavy metals from tailings in changing acid-based environment, especially in the Arctic area. To investigate how the temperature variation affected metal release from tailings in the Arctic area, a series of column leaching experiments was conducted under four temperature situations (5°C, 10°C, 14°C and 18°C). Physicochemical properties, Fe, Zn, Ni and Mn concentrations of leachates at each cycle were measured, and multivariate statistical analysis was applied to research the effect of temperature on heavy metals leaching from tailings in the Arctic area. The results showed that higher temperatures encouraged tailings to oxidation and sulfuration of and promoted heavy metal release from the tailings through precipitation and erosion. Ni, Zn and Mn have similar releasing resources from tailings and positive correlation in the leaching activity. Rising temperature accelerated Fe leaching; Fe leaching promoted leaching of the other metals, especially of Mn. Appropriately increase temperature will accelerate oxidization and sulfidization of the tailings, promote acid generation and increase TDS and, finally, promote the release of heavy metals. Climate change, with rising temperatures increasing the risk of heavy metals leaching from the tailings, should be given greater attention. Keeping tailings away from the appropriate temperature and in a higher alkalinity is a good method to control the leaching of heavy metals from tailings.","PeriodicalId":13895,"journal":{"name":"International Journal of Agricultural and Biological Engineering","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81630699","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
: In order to further reduce the damage rate in threshing seed corn, a seed corn threshing testbed with variable diameter and spacing that can realize dynamic adjustment of parameters, such as feed quantity, rotating speed of the threshing device, threshing spacing of the threshing units, was designed in this research. The software of finite element analysis ANSYS Workbench was applied to do modal analysis on the threshing axis designed for variable diameter and spacing of seed corn. The first 8 orders of natural frequencies were distributed in 201.12-1640.20 Hz, with corresponding vibration amplitude in 5.86-27.04 mm, showing reasonable structural design of the threshing axis, which could realize effective seed corn threshing and conveying. Discrete element method was applied to do simulation analysis on the seed corn threshing and conveying process with variable diameter and spacing. Under the condition of different feed quantity, different rotating speed of the thresher, the moving speed of corn clusters and contact force among clusters were measured through simulation, and the working characteristics of the threshing testbed for low-damage and dynamic threshing and conveying of seed corn with variable diameter and spacing were revealed. Working performance test results of the testbed of seed corn with variable diameter and spacing showed that, when the rotating speed of the threshing axis was 190-290 r/min, feed quantity was 1.80-3.80 kg/s, the damage rate of seed corn was 0.32%-0.63%, threshing rate was 99.20%-99.82%, and content impurity rate was 4.23%-5.86%, the mass of threshed corn grains first increased and then decreased along the axial direction. The test verification process was in line with the simulation results; thus, the test results could satisfy the requirements in design and actual operation.
{"title":"Analysis and performance test on dynamic seed corn threshing and conveying process with variable diameter and spacing","authors":"Fei Dai, Yuanxiang Liu, Ruijie Shi, Yiming Zhao, Shanglong Xin, Qiufeng Fu, Wuyun Zhao","doi":"10.25165/j.ijabe.20231602.7741","DOIUrl":"https://doi.org/10.25165/j.ijabe.20231602.7741","url":null,"abstract":": In order to further reduce the damage rate in threshing seed corn, a seed corn threshing testbed with variable diameter and spacing that can realize dynamic adjustment of parameters, such as feed quantity, rotating speed of the threshing device, threshing spacing of the threshing units, was designed in this research. The software of finite element analysis ANSYS Workbench was applied to do modal analysis on the threshing axis designed for variable diameter and spacing of seed corn. The first 8 orders of natural frequencies were distributed in 201.12-1640.20 Hz, with corresponding vibration amplitude in 5.86-27.04 mm, showing reasonable structural design of the threshing axis, which could realize effective seed corn threshing and conveying. Discrete element method was applied to do simulation analysis on the seed corn threshing and conveying process with variable diameter and spacing. Under the condition of different feed quantity, different rotating speed of the thresher, the moving speed of corn clusters and contact force among clusters were measured through simulation, and the working characteristics of the threshing testbed for low-damage and dynamic threshing and conveying of seed corn with variable diameter and spacing were revealed. Working performance test results of the testbed of seed corn with variable diameter and spacing showed that, when the rotating speed of the threshing axis was 190-290 r/min, feed quantity was 1.80-3.80 kg/s, the damage rate of seed corn was 0.32%-0.63%, threshing rate was 99.20%-99.82%, and content impurity rate was 4.23%-5.86%, the mass of threshed corn grains first increased and then decreased along the axial direction. The test verification process was in line with the simulation results; thus, the test results could satisfy the requirements in design and actual operation.","PeriodicalId":13895,"journal":{"name":"International Journal of Agricultural and Biological Engineering","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88279331","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.25165/j.ijabe.20231601.6918
Chao Meng, Wei Yang, Xinjian Ren, D. Wang, Minzan Li
{"title":"In-situ soil texture classification and physical clay content measurement based on multi-source information fusion","authors":"Chao Meng, Wei Yang, Xinjian Ren, D. Wang, Minzan Li","doi":"10.25165/j.ijabe.20231601.6918","DOIUrl":"https://doi.org/10.25165/j.ijabe.20231601.6918","url":null,"abstract":"","PeriodicalId":13895,"journal":{"name":"International Journal of Agricultural and Biological Engineering","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74853254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.25165/j.ijabe.20231601.6581
Lifeng Xu, Zhongzhuo Yang, Zusheng Huang, Weilong Ding, G. Buck-Sorlin
{"title":"Effects of flight parameters for plant protection UAV on droplets deposition rate based on a 3D simulation approach","authors":"Lifeng Xu, Zhongzhuo Yang, Zusheng Huang, Weilong Ding, G. Buck-Sorlin","doi":"10.25165/j.ijabe.20231601.6581","DOIUrl":"https://doi.org/10.25165/j.ijabe.20231601.6581","url":null,"abstract":"","PeriodicalId":13895,"journal":{"name":"International Journal of Agricultural and Biological Engineering","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80581357","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.25165/j.ijabe.20231603.7812
Xinping Sun, Hua Li, Xindan Qi, Dinghao Feng, Jianqi Zhou, Yongjian Wang, Samuel Mbugua Nyambura, Xiaoyu Zhang, Xi Chen
This study aimed to optimize a three-row air-suction Brassica chinensis precision metering device to improve the low seeding performance. ANSYS 17.0 Software was used to analyze the effect of different numbers of suction holes and different suction hole structures on the airflow field. It was found that a suction hole number of 60 was beneficial to the flow field stability and a conical hole structure was beneficial to the adsorption of seeds. Box-Behnken design experiments were carried out with negative pressure, rotational speed, and hole diameter as the experimental factors. The optimal parameter combination was achieved when the negative pressure was 3.96 kPa, the rotational speed of the seeding plate was 1.49 rad/s and the hole diameter was 1.10 mm. The qualification rate of inner, middle, and outer rings were 87.580%, 90.548%, and 90.117%, respectively, and the miss seeding rate of inner, middle, and outer rings were 10.915%, 7.139%, and 5.920%, respectively. Keywords: Brassica chinensis, metering device, airflow field, Box-Behnken design DOI: 10.25165/j.ijabe.20231603.7812 Citation: Sun X P, Li H, Qi X D, Feng D H, Zhou J Q, Wang Y J, et al. Optimization of a three-row air-suction Brassica chinensis precision metering device based on CFD-DEM coupling simulation. Int J Agric & Biol Eng, 2023; 16(3): 130–142.
{"title":"Optimization of a three-row air-suction Brassica chinensis precision metering device based on CFD-DEM coupling simulation","authors":"Xinping Sun, Hua Li, Xindan Qi, Dinghao Feng, Jianqi Zhou, Yongjian Wang, Samuel Mbugua Nyambura, Xiaoyu Zhang, Xi Chen","doi":"10.25165/j.ijabe.20231603.7812","DOIUrl":"https://doi.org/10.25165/j.ijabe.20231603.7812","url":null,"abstract":"This study aimed to optimize a three-row air-suction Brassica chinensis precision metering device to improve the low seeding performance. ANSYS 17.0 Software was used to analyze the effect of different numbers of suction holes and different suction hole structures on the airflow field. It was found that a suction hole number of 60 was beneficial to the flow field stability and a conical hole structure was beneficial to the adsorption of seeds. Box-Behnken design experiments were carried out with negative pressure, rotational speed, and hole diameter as the experimental factors. The optimal parameter combination was achieved when the negative pressure was 3.96 kPa, the rotational speed of the seeding plate was 1.49 rad/s and the hole diameter was 1.10 mm. The qualification rate of inner, middle, and outer rings were 87.580%, 90.548%, and 90.117%, respectively, and the miss seeding rate of inner, middle, and outer rings were 10.915%, 7.139%, and 5.920%, respectively. Keywords: Brassica chinensis, metering device, airflow field, Box-Behnken design DOI: 10.25165/j.ijabe.20231603.7812 Citation: Sun X P, Li H, Qi X D, Feng D H, Zhou J Q, Wang Y J, et al. Optimization of a three-row air-suction Brassica chinensis precision metering device based on CFD-DEM coupling simulation. Int J Agric & Biol Eng, 2023; 16(3): 130–142.","PeriodicalId":13895,"journal":{"name":"International Journal of Agricultural and Biological Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135358842","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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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