Background Zonal application maps are designed to represent field variability using key variables that can be translated into tailored management practices.For cotton,zonal maps for crop growth regulator(CGR)applicati...Background Zonal application maps are designed to represent field variability using key variables that can be translated into tailored management practices.For cotton,zonal maps for crop growth regulator(CGR)applications under variable-rate(VR)strategies are commonly based exclusively on vegetation indices(VIs)variability.However,VIs often saturate in dense crop vegetation areas,limiting their effectiveness in distinguishing variability in crop growth.This study aimed to compare unsupervised framework(UF)and supervised framework(SUF)approaches for generat-ing zonal application maps for CGR under VR conditions.During 2022-2023 agricultural seasons,an UF was employed to generate zonal maps based on locally collected field data on plant height of cotton,satellite imagery,soil texture,and phenology data.Subsequently,a SUF(based on historical data between 2020-2021 to 2022-2023 agricultural seasons)was developed to predict plant height using remote sensing and phenology data,aiming to replicate same zonal maps but without relying on direct field measurements of plant height.Both approaches were tested in three fields and on two different dates per field.Results The predictive model for plant height of SUF performed well,as indicated by the model metrics.However,when comparing zonal application maps for specific field-date combinations,the predicted plant height exhibited lower variability compared with field measurements.This led to variable compatibility between SUF maps,which utilized the model predictions,and the UF maps,which were based on the real field data.Fields characterized by much pronounced soil texture variability yielded the highest compatibility between the zonal application maps produced by both SUF and UF approaches.This was predominantly due to the greater consistency in estimating plant development patterns within these heterogeneous field environments.While VR application approach can facilitate product savings during the application operation,other key factors must be considered.These include the availability of specialized machinery required for this type of applications,as well as the inherent operational costs associated with applying a single CGR product which differs from the typical uniform rate applications that often integrate multi-ple inputs.Conclusion Predictive modeling shows promise for assisting in the creation of zonal application maps for VR of CGR applications.However,the degree of agreement with the actual variability in crop growth found in the field should be evaluated on a field-by-field basis.The SUF approach,which is based on plant heigh prediction,demonstrated potential for supporting the development of zonal application maps for VR of CGR applications.However,the degree to which this approach aligns itself with the actual variability in crop growth observed in the field may vary,necessi-tating field-by-field evaluation.展开更多
随着数字经济的快速发展,对三维重建技术的需求显著增加。然而,现有商用三维重建系统多依赖于封闭的单机或集群架构,导致灵活性和效率受限,而开源框架在绝对坐标和尺度恢复方面存在不足。对此,提出了一种基于GCP(Ground Control Point)...随着数字经济的快速发展,对三维重建技术的需求显著增加。然而,现有商用三维重建系统多依赖于封闭的单机或集群架构,导致灵活性和效率受限,而开源框架在绝对坐标和尺度恢复方面存在不足。对此,提出了一种基于GCP(Ground Control Point)辅助的Colmap框架中的SFM(Structure from Motion)算法。该算法通过构建残差方程、应用相似变换和全局光束法平差,将Colmap中SFM的自由网结果精确转换为绝对坐标。实验结果表明,该方法在计算精度上与商用系统Agisoft和大疆智图相当,且在尺度恢复上保持了较高的计算效率。所提方法不仅提升了开源三维重建系统的绝对尺度恢复能力,还为未来云端应用和大规模数据处理提供了理论和实践基础。未来将致力于实现全流程自动化三维重建的云架构,并探讨与物联网设备在三维监管中的应用前景。展开更多
文摘Background Zonal application maps are designed to represent field variability using key variables that can be translated into tailored management practices.For cotton,zonal maps for crop growth regulator(CGR)applications under variable-rate(VR)strategies are commonly based exclusively on vegetation indices(VIs)variability.However,VIs often saturate in dense crop vegetation areas,limiting their effectiveness in distinguishing variability in crop growth.This study aimed to compare unsupervised framework(UF)and supervised framework(SUF)approaches for generat-ing zonal application maps for CGR under VR conditions.During 2022-2023 agricultural seasons,an UF was employed to generate zonal maps based on locally collected field data on plant height of cotton,satellite imagery,soil texture,and phenology data.Subsequently,a SUF(based on historical data between 2020-2021 to 2022-2023 agricultural seasons)was developed to predict plant height using remote sensing and phenology data,aiming to replicate same zonal maps but without relying on direct field measurements of plant height.Both approaches were tested in three fields and on two different dates per field.Results The predictive model for plant height of SUF performed well,as indicated by the model metrics.However,when comparing zonal application maps for specific field-date combinations,the predicted plant height exhibited lower variability compared with field measurements.This led to variable compatibility between SUF maps,which utilized the model predictions,and the UF maps,which were based on the real field data.Fields characterized by much pronounced soil texture variability yielded the highest compatibility between the zonal application maps produced by both SUF and UF approaches.This was predominantly due to the greater consistency in estimating plant development patterns within these heterogeneous field environments.While VR application approach can facilitate product savings during the application operation,other key factors must be considered.These include the availability of specialized machinery required for this type of applications,as well as the inherent operational costs associated with applying a single CGR product which differs from the typical uniform rate applications that often integrate multi-ple inputs.Conclusion Predictive modeling shows promise for assisting in the creation of zonal application maps for VR of CGR applications.However,the degree of agreement with the actual variability in crop growth found in the field should be evaluated on a field-by-field basis.The SUF approach,which is based on plant heigh prediction,demonstrated potential for supporting the development of zonal application maps for VR of CGR applications.However,the degree to which this approach aligns itself with the actual variability in crop growth observed in the field may vary,necessi-tating field-by-field evaluation.
文摘随着数字经济的快速发展,对三维重建技术的需求显著增加。然而,现有商用三维重建系统多依赖于封闭的单机或集群架构,导致灵活性和效率受限,而开源框架在绝对坐标和尺度恢复方面存在不足。对此,提出了一种基于GCP(Ground Control Point)辅助的Colmap框架中的SFM(Structure from Motion)算法。该算法通过构建残差方程、应用相似变换和全局光束法平差,将Colmap中SFM的自由网结果精确转换为绝对坐标。实验结果表明,该方法在计算精度上与商用系统Agisoft和大疆智图相当,且在尺度恢复上保持了较高的计算效率。所提方法不仅提升了开源三维重建系统的绝对尺度恢复能力,还为未来云端应用和大规模数据处理提供了理论和实践基础。未来将致力于实现全流程自动化三维重建的云架构,并探讨与物联网设备在三维监管中的应用前景。