Assuming uniform albedo and Lambertian surface for the imaging model, a new robust method for estimation of illuminant direction and albedo from shading is presented. If there is a singular point with maximum intensit...Assuming uniform albedo and Lambertian surface for the imaging model, a new robust method for estimation of illuminant direction and albedo from shading is presented. If there is a singular point with maximum intensity in an image, the method use shading information of the singular point and its neighbors to estimate directly the elevation of illuminant direction, surface albedo, and the bias brightness. Some experiment results on synthetic images are given to illustrate the new approach is accurate and robust.展开更多
Concentrations of Iron (Fe), As, and Cu in soil samples from the fields near the Baoshan Mine in Hunan Province, China, were analyzed and soil spectral reflectance was measured with an ASD FieldSpec FR spectroradiomet...Concentrations of Iron (Fe), As, and Cu in soil samples from the fields near the Baoshan Mine in Hunan Province, China, were analyzed and soil spectral reflectance was measured with an ASD FieldSpec FR spectroradiometer (Analytical Spectral Devices, Inc., USA) under laboratory condition. Partial least square regression (PLSR) models were constructed for predicting soil metal concentrations. The data pre-processing methods, first and second derivatives (FD and SD), baseline correction (BC), standard normal variate (SNV), multiplicative scatter correction (MSC), and continuum removal (CR), were used for the spectral reflectance data pretreatments. Then, the prediction results were evaluated by relative root mean square error (RRMSE) and coefficients of determination (R 2 ). According to the criteria of minimal RRMSE and maximal R 2 , the PLSR models with the FD pretreatment (RRMSE = 0.24, R 2 = 0.61), SNV pretreatment (RRMSE = 0.08, R 2 = 0.78), and BC-pretreatment (RRMSE = 0.20, R 2 = 0.41) were considered as the final models for predicting As, Fe, and Cu, respectively. Wavebands at around 460, 1 400, 1 900, and 2 200 nm were selected as important spectral variables to construct final models. In conclusion, concentrations of heavy metals in contaminated soils could be indirectly assessed by soil spectra according to the correlation between the spectrally featureless components and Fe; therefore, spectral reflectance would be an alternative tool for monitoring soil heavy metals contamination.展开更多
Deep drilling data on seismogenic faults that are obtained directly can help in understanding earthquake mechanisms and the resulting changes in deep structure and material composition.However,geophysical data are nec...Deep drilling data on seismogenic faults that are obtained directly can help in understanding earthquake mechanisms and the resulting changes in deep structure and material composition.However,geophysical data are necessary to ensure that the planned borehole accurately drills through the target faults.In this study,the deep crustal structure of the Longmenshan fault is explored to obtain seismogenic fault characteristics of the Wenchuan earthquake.A scientific drilling project,Wenchuan Earthquake Fault Scientific Drilling No.4 Borehole(WFSD-4)is proposed with a borehole designed to drill through the north section of the fault zone while penetrating as many geological bodies and target layers related to seismogenic fault slip as possible.High-precision seismic exploration is then carried out to study the deep structure of the fault zone and achieve the scientific objective of the borehole.Two high-precision deep seismic reflection lines were arranged perpendicularly to the fault zone,and data were obtained through special acquisition schemes and processing methods.Finally,the surface position and drilling depth route of WFSD-4 are determined based on the interpretation results of seismic profiles.The seismic reflection method for site selection of the Wenchuan earthquake fault scientific drilling is proven feasible by comparing the interpretation with the actual drilling results,laying the foundation for further study on the deep structures of fault zones.展开更多
The paper puts forward a method of virtual keyboard key positioning based on infrared laser reflection and image processing technology. In this paper, the positioning principle is introduced first. And the experimenta...The paper puts forward a method of virtual keyboard key positioning based on infrared laser reflection and image processing technology. In this paper, the positioning principle is introduced first. And the experimental system is established based on image acquisition, image transformation, threshold selection and binarization processing and identification of key placement. Tested in the indoor environment, the method can achieve characters input efficiently and accurately. And the key positioning has high accuracy, validity and reliability. So the method which has a high practical value provides a good theoretical basis for design of virtual keyboard application.展开更多
TIRF microscopy has provided a means to view mobile granules within 100 nm in size in two dimensions.However quantitative analysis of the position and motion of those granules requires an appropriate tracking method.I...TIRF microscopy has provided a means to view mobile granules within 100 nm in size in two dimensions.However quantitative analysis of the position and motion of those granules requires an appropriate tracking method.In this paper,we present a new tracking algorithm combined with the unique features of TIRF.Firstly a fluorescence correction procedure was processed to solve the problem of fluorescence bleaching over time.Mobile granules were then segmented from a time-lapse image stack by an adaptive background subtraction method.Kalman filter was introduced to estimate and track the granules that allowed reducing searching range and hence greater reliability in tracking process.After the tracked granules were located in x-y plane,the z-position was indirectly inferred from the changes in their intensities.In the experiments the algorithm was applied in tracking GLUT4 vesicles in living adipose cells.The results indicate that the algorithm has achieved robust estimation and tracking of the vesicles in three dimensions.展开更多
The use of visible-near infrared (NIR) spectroscopy was explored as a tool to discriminate two new tomato plant varieties in China (Zheza205 and Zheza207). In this study, 82 top-canopy leaves of Zheza205 and 86 top-ca...The use of visible-near infrared (NIR) spectroscopy was explored as a tool to discriminate two new tomato plant varieties in China (Zheza205 and Zheza207). In this study, 82 top-canopy leaves of Zheza205 and 86 top-canopy leaves of Zheza207 were measured in visible-NIR reflectance mode. Discriminant models were developed using principal component analysis (PCA), discriminant analysis (DA), and discriminant partial least squares (DPLS) regression methods. After outliers detection, the samples were randomly split into two sets, one used as a calibration set (n=82) and the remaining samples as a validation set (n=82). When predicting the variety of the samples in validation set, the classification correctness of the DPLS model after optimizing spectral pretreatment was up to 93%. The DPLS model with raw spectra after multiplicative scatter cor- rection and Savitzky-Golay filter smoothing pretreatments had the best satisfactory calibration and prediction abilities (correlation coefficient of calibration (Rc)=0.920, root mean square errors of calibration=0.196, and root mean square errors of predic- tion=0.216). The results show that visible-NIR spectroscopy might be a suitable alternative tool to discriminate tomato plant varieties on-site.展开更多
文摘Assuming uniform albedo and Lambertian surface for the imaging model, a new robust method for estimation of illuminant direction and albedo from shading is presented. If there is a singular point with maximum intensity in an image, the method use shading information of the singular point and its neighbors to estimate directly the elevation of illuminant direction, surface albedo, and the bias brightness. Some experiment results on synthetic images are given to illustrate the new approach is accurate and robust.
基金Project supported by the National Natural Science Foundation of China (No. 40571130)the Natural Science Foundation of Shanghai, China (No. 07ZR14032)
文摘Concentrations of Iron (Fe), As, and Cu in soil samples from the fields near the Baoshan Mine in Hunan Province, China, were analyzed and soil spectral reflectance was measured with an ASD FieldSpec FR spectroradiometer (Analytical Spectral Devices, Inc., USA) under laboratory condition. Partial least square regression (PLSR) models were constructed for predicting soil metal concentrations. The data pre-processing methods, first and second derivatives (FD and SD), baseline correction (BC), standard normal variate (SNV), multiplicative scatter correction (MSC), and continuum removal (CR), were used for the spectral reflectance data pretreatments. Then, the prediction results were evaluated by relative root mean square error (RRMSE) and coefficients of determination (R 2 ). According to the criteria of minimal RRMSE and maximal R 2 , the PLSR models with the FD pretreatment (RRMSE = 0.24, R 2 = 0.61), SNV pretreatment (RRMSE = 0.08, R 2 = 0.78), and BC-pretreatment (RRMSE = 0.20, R 2 = 0.41) were considered as the final models for predicting As, Fe, and Cu, respectively. Wavebands at around 460, 1 400, 1 900, and 2 200 nm were selected as important spectral variables to construct final models. In conclusion, concentrations of heavy metals in contaminated soils could be indirectly assessed by soil spectra according to the correlation between the spectrally featureless components and Fe; therefore, spectral reflectance would be an alternative tool for monitoring soil heavy metals contamination.
基金supported by the“Deep Structure and Variation Characteristics of Fracture Shear Band of the Longmenshan Fault Zone”of the National Natural Science Foundation of China (No.42174123)the“Wenchuan Earthquake Fault Scientific Drilling”of the National Science and Technology Planning Project and the“3D Geological Mapping of Longmenshan Fault Zone”Project of the CGS China Geological Survey (No.1212011220265).
文摘Deep drilling data on seismogenic faults that are obtained directly can help in understanding earthquake mechanisms and the resulting changes in deep structure and material composition.However,geophysical data are necessary to ensure that the planned borehole accurately drills through the target faults.In this study,the deep crustal structure of the Longmenshan fault is explored to obtain seismogenic fault characteristics of the Wenchuan earthquake.A scientific drilling project,Wenchuan Earthquake Fault Scientific Drilling No.4 Borehole(WFSD-4)is proposed with a borehole designed to drill through the north section of the fault zone while penetrating as many geological bodies and target layers related to seismogenic fault slip as possible.High-precision seismic exploration is then carried out to study the deep structure of the fault zone and achieve the scientific objective of the borehole.Two high-precision deep seismic reflection lines were arranged perpendicularly to the fault zone,and data were obtained through special acquisition schemes and processing methods.Finally,the surface position and drilling depth route of WFSD-4 are determined based on the interpretation results of seismic profiles.The seismic reflection method for site selection of the Wenchuan earthquake fault scientific drilling is proven feasible by comparing the interpretation with the actual drilling results,laying the foundation for further study on the deep structures of fault zones.
文摘The paper puts forward a method of virtual keyboard key positioning based on infrared laser reflection and image processing technology. In this paper, the positioning principle is introduced first. And the experimental system is established based on image acquisition, image transformation, threshold selection and binarization processing and identification of key placement. Tested in the indoor environment, the method can achieve characters input efficiently and accurately. And the key positioning has high accuracy, validity and reliability. So the method which has a high practical value provides a good theoretical basis for design of virtual keyboard application.
基金Project supported by the National Natural Science Foundation ofChina (No. 30770596)the Key Laboratory for Biomedical En-gineering of Ministry of Education of China
文摘TIRF microscopy has provided a means to view mobile granules within 100 nm in size in two dimensions.However quantitative analysis of the position and motion of those granules requires an appropriate tracking method.In this paper,we present a new tracking algorithm combined with the unique features of TIRF.Firstly a fluorescence correction procedure was processed to solve the problem of fluorescence bleaching over time.Mobile granules were then segmented from a time-lapse image stack by an adaptive background subtraction method.Kalman filter was introduced to estimate and track the granules that allowed reducing searching range and hence greater reliability in tracking process.After the tracked granules were located in x-y plane,the z-position was indirectly inferred from the changes in their intensities.In the experiments the algorithm was applied in tracking GLUT4 vesicles in living adipose cells.The results indicate that the algorithm has achieved robust estimation and tracking of the vesicles in three dimensions.
基金Project (No.60405003) supported by the National Natural Science Foundation of China
文摘The use of visible-near infrared (NIR) spectroscopy was explored as a tool to discriminate two new tomato plant varieties in China (Zheza205 and Zheza207). In this study, 82 top-canopy leaves of Zheza205 and 86 top-canopy leaves of Zheza207 were measured in visible-NIR reflectance mode. Discriminant models were developed using principal component analysis (PCA), discriminant analysis (DA), and discriminant partial least squares (DPLS) regression methods. After outliers detection, the samples were randomly split into two sets, one used as a calibration set (n=82) and the remaining samples as a validation set (n=82). When predicting the variety of the samples in validation set, the classification correctness of the DPLS model after optimizing spectral pretreatment was up to 93%. The DPLS model with raw spectra after multiplicative scatter cor- rection and Savitzky-Golay filter smoothing pretreatments had the best satisfactory calibration and prediction abilities (correlation coefficient of calibration (Rc)=0.920, root mean square errors of calibration=0.196, and root mean square errors of predic- tion=0.216). The results show that visible-NIR spectroscopy might be a suitable alternative tool to discriminate tomato plant varieties on-site.
