Facilitating non-contact measurement,a computer-imaging system was devised and evaluated to predict the chlorophyll content in potato leaves.A charge-coupled device(CCD)camera paired with two optical filters and light...Facilitating non-contact measurement,a computer-imaging system was devised and evaluated to predict the chlorophyll content in potato leaves.A charge-coupled device(CCD)camera paired with two optical filters and light chamber was used to acquire green(550±40 nm)and red band(700±40 nm)images from the same leaf.Potato leaves from 15 plants differing in coloration(green to yellow)and age were selected for this study.Histogram based image features,such as mean and variances of green and red band images,were extracted from the histogram.Regression analyses demonstrated that the variations in SPAD meter reading could be explained by themeangrayandvariances of gray scale values.The fitted least square models based on the mean gray scale levels were inversely related to the chlorophyll content of the potato leaf with a R^2 of 0.87 using a green band image and with an R2 of 0.79 using a red band image.With the extracted four image features,the developed multiple linear regression model predicted the chlorophyll content with a high R^2 of 0.88).The multiple regression model(using all features)provided an average prediction accuracy of 85.08% and amaximum accuracy of 99.8%.The prediction model using only mean gray value of red band showed an average accuracy of 81.6% with a maximum accuracy of 99.14%.展开更多
By using computer imaging analysis system combined with light microscopy, the glomeruli lesions on biopsy specimens sections were quantitatively analysed. The patholoical changes of mesangial proliferative glomerulone...By using computer imaging analysis system combined with light microscopy, the glomeruli lesions on biopsy specimens sections were quantitatively analysed. The patholoical changes of mesangial proliferative glomerulonephritis (MsPGN) in children were quantitatively evaluated and the correlation between the mesangial matrix area (MA) and some clinical data were also analysed. The results indicated that the levels of various glomerular parameters in MsPGN group were higher than those of normal controls. No correlation was found between MA and 24 h urinary protein excretion, but a negative correlation was revealed between MA and estimated GFR. MA was also correlated with the duration of MsPGN recovery. It was suggested that the quantitative analysis of glomerular parameters by computer is a reproducible methods. The parameter of MA may be used for evaluation of the renal function, determination of the duration of therapy and evaluation of prognosis of MsPGN in children.展开更多
文摘Facilitating non-contact measurement,a computer-imaging system was devised and evaluated to predict the chlorophyll content in potato leaves.A charge-coupled device(CCD)camera paired with two optical filters and light chamber was used to acquire green(550±40 nm)and red band(700±40 nm)images from the same leaf.Potato leaves from 15 plants differing in coloration(green to yellow)and age were selected for this study.Histogram based image features,such as mean and variances of green and red band images,were extracted from the histogram.Regression analyses demonstrated that the variations in SPAD meter reading could be explained by themeangrayandvariances of gray scale values.The fitted least square models based on the mean gray scale levels were inversely related to the chlorophyll content of the potato leaf with a R^2 of 0.87 using a green band image and with an R2 of 0.79 using a red band image.With the extracted four image features,the developed multiple linear regression model predicted the chlorophyll content with a high R^2 of 0.88).The multiple regression model(using all features)provided an average prediction accuracy of 85.08% and amaximum accuracy of 99.8%.The prediction model using only mean gray value of red band showed an average accuracy of 81.6% with a maximum accuracy of 99.14%.
文摘By using computer imaging analysis system combined with light microscopy, the glomeruli lesions on biopsy specimens sections were quantitatively analysed. The patholoical changes of mesangial proliferative glomerulonephritis (MsPGN) in children were quantitatively evaluated and the correlation between the mesangial matrix area (MA) and some clinical data were also analysed. The results indicated that the levels of various glomerular parameters in MsPGN group were higher than those of normal controls. No correlation was found between MA and 24 h urinary protein excretion, but a negative correlation was revealed between MA and estimated GFR. MA was also correlated with the duration of MsPGN recovery. It was suggested that the quantitative analysis of glomerular parameters by computer is a reproducible methods. The parameter of MA may be used for evaluation of the renal function, determination of the duration of therapy and evaluation of prognosis of MsPGN in children.
