Aiming at the problems of single classification method and high classification cost of kiwifruit in China,we proposed a grading method based on kiwifruit surface defects.A set of kiwifruit image acquisition system was...Aiming at the problems of single classification method and high classification cost of kiwifruit in China,we proposed a grading method based on kiwifruit surface defects.A set of kiwifruit image acquisition system was built.The K-means clustering segmentation algorithm was used to segment the surface defects,and then color contrast was performed to determine whether it was a piece of defective fruit.Then,the shape features of normal fruit were extracted and an SVM classifier was designed to further determine its grade.This method has the advantages of low cost,simple algorithm and high efficiency,which opens a new way for fruit classification,and is of great significance to promoting the development of fruit classification industry in China and enhancing international competitiveness.展开更多
In order to solve the problems of TEV(transient earth voltage) utilization,such as single judgment criterion and low reliability of PD detection in HV switchboard,this paper discussed the method on how to make a bette...In order to solve the problems of TEV(transient earth voltage) utilization,such as single judgment criterion and low reliability of PD detection in HV switchboard,this paper discussed the method on how to make a better utilization of TEV in PD detection of metal-enclosed switchgears.Through discussing the relationship among the temporal phase,number of pulses and threshold of measuring and extracting the features corresponding to different typical defects,test results showed that the needle discharge distributed in 0°～90°and 200°～340°with low appearance probability above high measurement threshold;internal discharge distributed in 0°～90°and 270°～315°,and showed a similar decreasing trend under increasing of the threshold in the two regions;suspended discharge distributed in 0°～135°and 180°～315°where the PD in negative half periods decreased more seriously than those in positive half with increasing threshold.These results followed the doctrine of consistency with the conclusions that were obtained by using the traditional pulse current method.The possibility of using TEV method to make identification of PD defects has been proved to prepare for further research.展开更多
基金Supported by the Chinese Society of Logistics(2021CSLKT3-286)。
文摘Aiming at the problems of single classification method and high classification cost of kiwifruit in China,we proposed a grading method based on kiwifruit surface defects.A set of kiwifruit image acquisition system was built.The K-means clustering segmentation algorithm was used to segment the surface defects,and then color contrast was performed to determine whether it was a piece of defective fruit.Then,the shape features of normal fruit were extracted and an SVM classifier was designed to further determine its grade.This method has the advantages of low cost,simple algorithm and high efficiency,which opens a new way for fruit classification,and is of great significance to promoting the development of fruit classification industry in China and enhancing international competitiveness.
基金Supported by National Natural Science Foundation of China(50907051)
文摘In order to solve the problems of TEV(transient earth voltage) utilization,such as single judgment criterion and low reliability of PD detection in HV switchboard,this paper discussed the method on how to make a better utilization of TEV in PD detection of metal-enclosed switchgears.Through discussing the relationship among the temporal phase,number of pulses and threshold of measuring and extracting the features corresponding to different typical defects,test results showed that the needle discharge distributed in 0°～90°and 200°～340°with low appearance probability above high measurement threshold;internal discharge distributed in 0°～90°and 270°～315°,and showed a similar decreasing trend under increasing of the threshold in the two regions;suspended discharge distributed in 0°～135°and 180°～315°where the PD in negative half periods decreased more seriously than those in positive half with increasing threshold.These results followed the doctrine of consistency with the conclusions that were obtained by using the traditional pulse current method.The possibility of using TEV method to make identification of PD defects has been proved to prepare for further research.
