The Tarim River Basin(TRB)is a vast area with plenty of light and heat and is an important base for grain and cotton production in Northwest China.In the context of climate change,however,the increased frequency of ex...The Tarim River Basin(TRB)is a vast area with plenty of light and heat and is an important base for grain and cotton production in Northwest China.In the context of climate change,however,the increased frequency of extreme weather and climate events is having numerous negative impacts on the region's agricultural production.To better understand how unfavorable climatic conditions affect crop production,we explored the relationship of extreme weather and climate events with crop yields and phenology.In this research,ten indicators of extreme weather and climate events(consecutive dry days(CDD),min Tmax(TXn),max Tmin(TNx),tropical nights(TR),warm days(Tx90p),warm nights(Tn90p),summer days(SU),frost days(FD),very wet days(R95p),and windy days(WD))were selected to analyze the impact of spatial and temporal variations on the yields of major crops(wheat,maize,and cotton)in the TRB from 1990 to 2020.The three key findings of this research were as follows:extreme temperatures in southwestern TRB showed an increasing trend,with higher extreme temperatures at night,while the occurrence of extreme weather and climate events in northeastern TRB was relatively low.The number of FD was on the rise,while WD also increased in recent years.Crop yields were higher in the northeast compared with the southwest,and wheat,maize,and cotton yields generally showed an increasing trend despite an earlier decline.The correlation of extreme weather and climate events on crop yields can be categorized as extreme nighttime temperature indices(TNx,Tn90p,TR,and FD),extreme daytime temperature indices(TXn,Tx90p,and SU),extreme precipitation indices(CDD and R95p),and extreme wind(WD).By using Random Forest(RF)approach to determine the effects of different extreme weather and climate events on the yields of different crops,we found that the importance of extreme precipitation indices(CDD and R95p)to crop yield decreased significantly over time.As well,we found that the importance of the extreme nighttime temperature(TR and TNx)for the yields of the three crops increased during 2005-2020 compared with 1990-2005.The impact of extreme temperature events on wheat,maize,and cotton yields in the TRB is becoming increasingly significant,and this finding can inform policy decisions and agronomic innovations to better cope with current and future climate warming.展开更多
Village revitalization is a major development strategy in China,where village planning plays as its critical component.Taking village planning of De’an County in Jiangxi Province as an example,this paper explored the...Village revitalization is a major development strategy in China,where village planning plays as its critical component.Taking village planning of De’an County in Jiangxi Province as an example,this paper explored the significant importance of village planning in promoting rural revitalization along with its corresponding promote mechanisms.Through in-depth research on the detailed situation of village planning and implementation in Jiangxi,this paper summarized that some challenges exist,including backward planning,poor planning consciousness,difficulties in planning implementation.Based on these findings,the paper analyzed the challenges of village land resource scarcity,village images lacking in uniqueness features,and insufficient rural infrastructure construction.Furthermore,it proposed strategies such as taking the lead in planning from the beginning,advancing practical implementation at a high level,adhering to bottom-line thinking,and coordinating high-quality rural land protection and development,applying strategies such as ecological and pleasant living,building villages suitable for living and working,and construction of beautiful countryside,aiming to provide valuable reference for related research fields.展开更多
The real-time dynamic deformation monitoring of offshore platforms under environmental excitation is crucial to their safe operation.Although Global Navigation Satellite System-Precise Point Positioning(GNSS-PPP)has b...The real-time dynamic deformation monitoring of offshore platforms under environmental excitation is crucial to their safe operation.Although Global Navigation Satellite System-Precise Point Positioning(GNSS-PPP)has been considered for this purpose,its monitoring accuracy is relatively low.Moreover,the influence of background noise on the dynamic monitoring accuracy of GNSS-PPP remains unclear.Hence,it is imperative to further validate the feasibility of GNSS-PPP for deformation monitoring of offshore platforms.To address these concerns,vibration table tests with different amplitudes and frequencies are conducted.The results demonstrate that GNSS-PPP can effectively monitor horizontal vibration displacement as low as±30 mm,which is consistent with GNSS-RTK.Furthermore,the spectral characteristic of background noise in GNSS-PPP is similar to that of GNSS-RTK(Real Time Kinematic).Building on this observation,an improved Complete Ensemble Empirical Mode Decomposition with Adaptive Noise(CEEMDAN)has been proposed to de-noise the data and enhance the dynamic monitoring accuracy of GNSS-PPP.Field monitoring application research is also undertaken,successfully extracting and analyzing the dynamic deformation of an offshore platform structure under environmental excitation using GNSS-PPP monitoring in conjunction with improved CEEMDAN de-noising.By comparing the de-noised dynamic deformation trajectories of the offshore platform during different periods,it is observed that the platform exhibits reversible alternating vibration responses under environmental excitation,with more pronounced displacement deformation in the direction of load action.The research results confirm the feasibility and potential of GNSS-PPP for dynamic deformation monitoring of offshore platforms.展开更多
In order to improve target localization precision,accuracy,execution efficiency,and application range of the unmanned aerial vehicle(UAV)based on scene matching,a ground target localization method for unmanned aerial ...In order to improve target localization precision,accuracy,execution efficiency,and application range of the unmanned aerial vehicle(UAV)based on scene matching,a ground target localization method for unmanned aerial vehicle based on scene matching(GTLUAVSM)is proposed.The sugges-ted approach entails completing scene matching through a feature matching algorithm.Then,multi-sensor registration is optimized by robust estimation based on homologous registration.Finally,basemap generation and model solution are utilized to improve basemap correspondence and accom-plish aerial image positioning.Theoretical evidence and experimental verification demonstrate that GTLUAVSM can improve localization accuracy,speed,and precision while minimizing reliance on task equipment.展开更多
The important role of greenway non-mortorized systems in urban sustainable development was summarized,pointing out their potential value in improving the ecological environment,promoting healthy living,and enhancing c...The important role of greenway non-mortorized systems in urban sustainable development was summarized,pointing out their potential value in improving the ecological environment,promoting healthy living,and enhancing community connections.Based on the analysis on some cases of urban greenway construction in China,specific transformation models and strategies were proposed for greenway construction,which could integrate green spaces with non-mortorized system,so as to enhance the comprehensive efficiency of urban linear spaces.展开更多
针对传统图像处理算法对钢铁表面缺陷检测存在识别效率低、漏检误检率高等问题,提出了YOLOv8-DSG(Deformable Convolution Network Squeeze and Excitation Network Generalized Intersection over Union)钢铁表面缺陷检测算法。在传统Y...针对传统图像处理算法对钢铁表面缺陷检测存在识别效率低、漏检误检率高等问题,提出了YOLOv8-DSG(Deformable Convolution Network Squeeze and Excitation Network Generalized Intersection over Union)钢铁表面缺陷检测算法。在传统YOLOv8算法的基础上,首先在Backbone网络的C2f(Convolution to Feature)模块中嵌入了可变形卷积网络DCN(Deformable Convolution Network),增强了模型在复杂背景条件下的特征提取能力;其次,在Neck网络中引入了SE(Squeeze and Excitation Network)注意力模块,突出钢铁表面重要特征信息,提升了特征融合的丰富性;最后,利用GIOU(Generalized Intersection Over Union)损失函数代替原有的CIOU(Complete Intersection Over Union),相比CIOU,GIOU引入了最小包围框面积比率,可更准确衡量框的重合面积。实验结果表明,YOLOv8-DSG算法在NEU-DET数据集上平均精度mAP达到80%,相较于原YOLOv8算法,提高了3.3%,且误检、漏检率低,具有更高的检测精度和运算效率,可在质量检测方面发挥重要作用。展开更多
基金funded by the Tianshan Yingcai Program of the Xinjiang Uygur Autonomous Region(2022TSYCCX0038)the Youth Innovation Promotion Association of the Chinese Academy of Sciences(Y2022108)the Postdoctoral Fellowship Program of Chinese Postdoctoral Science Foundation(CPSF)(GZC20232962).
文摘The Tarim River Basin(TRB)is a vast area with plenty of light and heat and is an important base for grain and cotton production in Northwest China.In the context of climate change,however,the increased frequency of extreme weather and climate events is having numerous negative impacts on the region's agricultural production.To better understand how unfavorable climatic conditions affect crop production,we explored the relationship of extreme weather and climate events with crop yields and phenology.In this research,ten indicators of extreme weather and climate events(consecutive dry days(CDD),min Tmax(TXn),max Tmin(TNx),tropical nights(TR),warm days(Tx90p),warm nights(Tn90p),summer days(SU),frost days(FD),very wet days(R95p),and windy days(WD))were selected to analyze the impact of spatial and temporal variations on the yields of major crops(wheat,maize,and cotton)in the TRB from 1990 to 2020.The three key findings of this research were as follows:extreme temperatures in southwestern TRB showed an increasing trend,with higher extreme temperatures at night,while the occurrence of extreme weather and climate events in northeastern TRB was relatively low.The number of FD was on the rise,while WD also increased in recent years.Crop yields were higher in the northeast compared with the southwest,and wheat,maize,and cotton yields generally showed an increasing trend despite an earlier decline.The correlation of extreme weather and climate events on crop yields can be categorized as extreme nighttime temperature indices(TNx,Tn90p,TR,and FD),extreme daytime temperature indices(TXn,Tx90p,and SU),extreme precipitation indices(CDD and R95p),and extreme wind(WD).By using Random Forest(RF)approach to determine the effects of different extreme weather and climate events on the yields of different crops,we found that the importance of extreme precipitation indices(CDD and R95p)to crop yield decreased significantly over time.As well,we found that the importance of the extreme nighttime temperature(TR and TNx)for the yields of the three crops increased during 2005-2020 compared with 1990-2005.The impact of extreme temperature events on wheat,maize,and cotton yields in the TRB is becoming increasingly significant,and this finding can inform policy decisions and agronomic innovations to better cope with current and future climate warming.
文摘Village revitalization is a major development strategy in China,where village planning plays as its critical component.Taking village planning of De’an County in Jiangxi Province as an example,this paper explored the significant importance of village planning in promoting rural revitalization along with its corresponding promote mechanisms.Through in-depth research on the detailed situation of village planning and implementation in Jiangxi,this paper summarized that some challenges exist,including backward planning,poor planning consciousness,difficulties in planning implementation.Based on these findings,the paper analyzed the challenges of village land resource scarcity,village images lacking in uniqueness features,and insufficient rural infrastructure construction.Furthermore,it proposed strategies such as taking the lead in planning from the beginning,advancing practical implementation at a high level,adhering to bottom-line thinking,and coordinating high-quality rural land protection and development,applying strategies such as ecological and pleasant living,building villages suitable for living and working,and construction of beautiful countryside,aiming to provide valuable reference for related research fields.
基金financially supported by the National Key R&D Program of China(Grant No.2022YFB4200705)the National Natural Science Foundation of China(Grant No.52109146)。
文摘The real-time dynamic deformation monitoring of offshore platforms under environmental excitation is crucial to their safe operation.Although Global Navigation Satellite System-Precise Point Positioning(GNSS-PPP)has been considered for this purpose,its monitoring accuracy is relatively low.Moreover,the influence of background noise on the dynamic monitoring accuracy of GNSS-PPP remains unclear.Hence,it is imperative to further validate the feasibility of GNSS-PPP for deformation monitoring of offshore platforms.To address these concerns,vibration table tests with different amplitudes and frequencies are conducted.The results demonstrate that GNSS-PPP can effectively monitor horizontal vibration displacement as low as±30 mm,which is consistent with GNSS-RTK.Furthermore,the spectral characteristic of background noise in GNSS-PPP is similar to that of GNSS-RTK(Real Time Kinematic).Building on this observation,an improved Complete Ensemble Empirical Mode Decomposition with Adaptive Noise(CEEMDAN)has been proposed to de-noise the data and enhance the dynamic monitoring accuracy of GNSS-PPP.Field monitoring application research is also undertaken,successfully extracting and analyzing the dynamic deformation of an offshore platform structure under environmental excitation using GNSS-PPP monitoring in conjunction with improved CEEMDAN de-noising.By comparing the de-noised dynamic deformation trajectories of the offshore platform during different periods,it is observed that the platform exhibits reversible alternating vibration responses under environmental excitation,with more pronounced displacement deformation in the direction of load action.The research results confirm the feasibility and potential of GNSS-PPP for dynamic deformation monitoring of offshore platforms.
基金the National Key R&D Program of China(2022YFF0604502).
文摘In order to improve target localization precision,accuracy,execution efficiency,and application range of the unmanned aerial vehicle(UAV)based on scene matching,a ground target localization method for unmanned aerial vehicle based on scene matching(GTLUAVSM)is proposed.The sugges-ted approach entails completing scene matching through a feature matching algorithm.Then,multi-sensor registration is optimized by robust estimation based on homologous registration.Finally,basemap generation and model solution are utilized to improve basemap correspondence and accom-plish aerial image positioning.Theoretical evidence and experimental verification demonstrate that GTLUAVSM can improve localization accuracy,speed,and precision while minimizing reliance on task equipment.
文摘The important role of greenway non-mortorized systems in urban sustainable development was summarized,pointing out their potential value in improving the ecological environment,promoting healthy living,and enhancing community connections.Based on the analysis on some cases of urban greenway construction in China,specific transformation models and strategies were proposed for greenway construction,which could integrate green spaces with non-mortorized system,so as to enhance the comprehensive efficiency of urban linear spaces.
文摘针对传统图像处理算法对钢铁表面缺陷检测存在识别效率低、漏检误检率高等问题,提出了YOLOv8-DSG(Deformable Convolution Network Squeeze and Excitation Network Generalized Intersection over Union)钢铁表面缺陷检测算法。在传统YOLOv8算法的基础上,首先在Backbone网络的C2f(Convolution to Feature)模块中嵌入了可变形卷积网络DCN(Deformable Convolution Network),增强了模型在复杂背景条件下的特征提取能力;其次,在Neck网络中引入了SE(Squeeze and Excitation Network)注意力模块,突出钢铁表面重要特征信息,提升了特征融合的丰富性;最后,利用GIOU(Generalized Intersection Over Union)损失函数代替原有的CIOU(Complete Intersection Over Union),相比CIOU,GIOU引入了最小包围框面积比率,可更准确衡量框的重合面积。实验结果表明,YOLOv8-DSG算法在NEU-DET数据集上平均精度mAP达到80%,相较于原YOLOv8算法,提高了3.3%,且误检、漏检率低,具有更高的检测精度和运算效率,可在质量检测方面发挥重要作用。
