A statistical multimodal background model was described for moving object detection in video surveillance. The solution to some of the problems such as illumination changes, initialization of model with moving objects...A statistical multimodal background model was described for moving object detection in video surveillance. The solution to some of the problems such as illumination changes, initialization of model with moving objects, and shadows suppression was provided. The background samples were chosen by thresholding inter-frame differences, and the Gaussian kernel density estimation was used to estimate the probability density function of background intensity. Pixel's neighbor information was considered to remove noise due to camera jitter and small motion in the scene. The hue-max-min-diff color information was used to detect and suppress moving cast shadows. The effectiveness of the proposed method in the foreground segmentation was demonstrated in the traffic surveillance application.展开更多
[Objective] In this study, the relationship between the pigments and the color expression of leaves of colored-leaf plants was discussed. [Method] The colors of leaf blades of 6 kinds of plants were analyzed with the ...[Objective] In this study, the relationship between the pigments and the color expression of leaves of colored-leaf plants was discussed. [Method] The colors of leaf blades of 6 kinds of plants were analyzed with the Royal Horticultural Soci-ety Colour Chart. The chlorophyl content, carotenoids content and anthocyanin con-tent in leaf blades were determined. In addition, the color types of leaf blades, kinds of pigments, pigment contents and pigment distributions of 6 kinds of plants were compared. [Result] The chlorophyl contents ranked as Populus canadensis Moench （green leaves） 〉 Populus deltoids cv. Zhonghuahongye （purple green leaves） 〉 Populus euramericana cv. Quanhong （red leaves）; Acer palmatum Thunb. （green leaves） 〉 Acer palmatum cv. Atropurpureum （purple red leaves） 〉 Acer pal-matum Thunb. cv. Atropurpureum （red leaves）. The ranking of anthocyanin contents was just opposite. The chlorophyl content was negatively related to the anthocyanin content. The leaf color of plants is determined by various pigments. The more the chlorophyl is, the greener the leaf is. The more the anthocyanin is, the redder the leaf is. In the colored-leaf plants, the chlorophyl content represents about 80% of the content of pigments, the carotenoids content represents about 17%, and the an-thocyanin represents about 3%. There is a difference in the chlorophyl content be-tween colored-leaf plants and green plants. However, the relatively low chlorophyl content wil not hamper the normal life activities of colored-leaf plants. [Conclusion] We hoped to provide reference and basis for the production and landscaping of col-ored-leaf plants.展开更多
A method for shadow detection and compensation for color aerial images is presented. It is considered that the intensity value of each image pixel is the product of illumination function and ground object reflection, ...A method for shadow detection and compensation for color aerial images is presented. It is considered that the intensity value of each image pixel is the product of illumination function and ground object reflection, and the shadowed regions on the image are mainly caused by the short of illumination, so the information compensation for the shadowed regions should concentrate on the illumination adjustment of concerned area on the basis of the analysis of whole image. The shadow detection and compensation procedure proposed by this paper consists of four steps.展开更多
Objective To analyze the clinical and ultrasonographic imaging features of intraductal papillary mutinous neoplasm （1PMN） of the pancreas. Methods Twelve patients with IPMN underwent surgery between May 2005 and De...Objective To analyze the clinical and ultrasonographic imaging features of intraductal papillary mutinous neoplasm （1PMN） of the pancreas. Methods Twelve patients with IPMN underwent surgery between May 2005 and December 2008, including 4 （33.3%） with adenoma and 8 （66.7%） with adenocarcinoma. IPMN was classified preoperatively into 3 types based on sonographic findings of different sites： main duct, branch duct, and combined type. All clinical presentations and ultrasonographic findings of those paticnts were reviewed and the correlation be- tween ultrasonographic hndings and histopathological results was analyzed. Results There were 9 men and 3 women with a mean age of 60.1±9.6 years （range, 32-73）. OF all the 12 patients with IPMN, 9 （75.0%） had experienced some symptoms of epigastric discomfort and/or pain as cell as backache; 7 cases were with medical history of acute pancreatitis, 5 cases with diabetes, 4 cases with elevated CA19-9, and 2 cases with steatorrhea. All lesions of IPMN have been revealed by transabdominal ul- trasonography. The mean diameters of the lesions were 1.4±0.8 cm （range, 0.5-2.0） and 6.3±6.0 cm （range, 2.0-20.0） in adenomas and adenocarcinomas, respectively. And the mean diameters of the main duct in adelnomas and adenocarcinomas were 1.0±0.8 cm and 1.6±1.0 cm, respectively. Among the 4 adnomas, 3 （75.0%） cases were classified as branch type based on sonographic findings, and 2 were demonstrated as mural nodules in which no color signals was detected. Among the 8 adenocarcinomas, 5 （62.5%） cases were classifled as main duct type, and 3 （37.5%） as combined type. In 7 of the 8 adcnocarcinomas, mural nodules were detected within the dilated ducts or cysts of the lesions in which color flow signals were detected. Conclusions Transabdominal ultrasonography can reveal the pancreatic cystic lesions of IPMN as well as dilated pancreatic： ducts. Some characteristics should be noticed as suggesting the possibility of malignancy： clinical symptoms of pancreatic insufficiency, large tumor size, and mural nodules with color Doppler flow signals. Transabdominal ultrasonography could be a useful tool to help diagnose and make appropriate management of IPMN.展开更多
This paper analyzes the correctly-expanded supersonic jet from a convergent-divergent axisymmetric nozzle by using numerical simulation of turbulent flow.And the calculated density distributions in this flow are compa...This paper analyzes the correctly-expanded supersonic jet from a convergent-divergent axisymmetric nozzle by using numerical simulation of turbulent flow.And the calculated density distributions in this flow are compared with the present experimental data using rainbow schlieren deflectometry.The value of the density from the experimental data agrees well with the results calculated by this simulation.Therefore,the present method of the measurement using rainbow schlieren deflectometry is useful for the measurement of the density of the correctly-expanded supersonic jet.展开更多
In the three-dimensional(3D) contour measurement,the phase shift profilometry(PSP) method is the most widely used one.However,the measurement speed of PSP is very low because of the multiple projections.In order to im...In the three-dimensional(3D) contour measurement,the phase shift profilometry(PSP) method is the most widely used one.However,the measurement speed of PSP is very low because of the multiple projections.In order to improve the measurement speed,color grating stripes are used for measurement in this paper.During the measurement,only one color sinusoidal fringe is projected on the measured object.Therefore,the measurement speed is greatly improved.Since there is coupling or interference phenomenon between the adjacent color grating stripes,a color correction method is used to improve the measurement results.A method for correcting nonlinear error of measurement system is proposed in this paper,and the sinusoidal property of acquired image after correction is better than that before correction.Experimental results show that with these correction methods,the measurement errors can be reduced.Therefore,it can support a good foundation for the high-precision 3D reconstruction.展开更多
文摘A statistical multimodal background model was described for moving object detection in video surveillance. The solution to some of the problems such as illumination changes, initialization of model with moving objects, and shadows suppression was provided. The background samples were chosen by thresholding inter-frame differences, and the Gaussian kernel density estimation was used to estimate the probability density function of background intensity. Pixel's neighbor information was considered to remove noise due to camera jitter and small motion in the scene. The hue-max-min-diff color information was used to detect and suppress moving cast shadows. The effectiveness of the proposed method in the foreground segmentation was demonstrated in the traffic surveillance application.
基金Supported by the Technology Research and Development Program of Beijing Vocational College of Agriculture(XY-YF-13-39)~~
文摘[Objective] In this study, the relationship between the pigments and the color expression of leaves of colored-leaf plants was discussed. [Method] The colors of leaf blades of 6 kinds of plants were analyzed with the Royal Horticultural Soci-ety Colour Chart. The chlorophyl content, carotenoids content and anthocyanin con-tent in leaf blades were determined. In addition, the color types of leaf blades, kinds of pigments, pigment contents and pigment distributions of 6 kinds of plants were compared. [Result] The chlorophyl contents ranked as Populus canadensis Moench （green leaves） 〉 Populus deltoids cv. Zhonghuahongye （purple green leaves） 〉 Populus euramericana cv. Quanhong （red leaves）; Acer palmatum Thunb. （green leaves） 〉 Acer palmatum cv. Atropurpureum （purple red leaves） 〉 Acer pal-matum Thunb. cv. Atropurpureum （red leaves）. The ranking of anthocyanin contents was just opposite. The chlorophyl content was negatively related to the anthocyanin content. The leaf color of plants is determined by various pigments. The more the chlorophyl is, the greener the leaf is. The more the anthocyanin is, the redder the leaf is. In the colored-leaf plants, the chlorophyl content represents about 80% of the content of pigments, the carotenoids content represents about 17%, and the an-thocyanin represents about 3%. There is a difference in the chlorophyl content be-tween colored-leaf plants and green plants. However, the relatively low chlorophyl content wil not hamper the normal life activities of colored-leaf plants. [Conclusion] We hoped to provide reference and basis for the production and landscaping of col-ored-leaf plants.
文摘A method for shadow detection and compensation for color aerial images is presented. It is considered that the intensity value of each image pixel is the product of illumination function and ground object reflection, and the shadowed regions on the image are mainly caused by the short of illumination, so the information compensation for the shadowed regions should concentrate on the illumination adjustment of concerned area on the basis of the analysis of whole image. The shadow detection and compensation procedure proposed by this paper consists of four steps.
文摘Objective To analyze the clinical and ultrasonographic imaging features of intraductal papillary mutinous neoplasm （1PMN） of the pancreas. Methods Twelve patients with IPMN underwent surgery between May 2005 and December 2008, including 4 （33.3%） with adenoma and 8 （66.7%） with adenocarcinoma. IPMN was classified preoperatively into 3 types based on sonographic findings of different sites： main duct, branch duct, and combined type. All clinical presentations and ultrasonographic findings of those paticnts were reviewed and the correlation be- tween ultrasonographic hndings and histopathological results was analyzed. Results There were 9 men and 3 women with a mean age of 60.1±9.6 years （range, 32-73）. OF all the 12 patients with IPMN, 9 （75.0%） had experienced some symptoms of epigastric discomfort and/or pain as cell as backache; 7 cases were with medical history of acute pancreatitis, 5 cases with diabetes, 4 cases with elevated CA19-9, and 2 cases with steatorrhea. All lesions of IPMN have been revealed by transabdominal ul- trasonography. The mean diameters of the lesions were 1.4±0.8 cm （range, 0.5-2.0） and 6.3±6.0 cm （range, 2.0-20.0） in adenomas and adenocarcinomas, respectively. And the mean diameters of the main duct in adelnomas and adenocarcinomas were 1.0±0.8 cm and 1.6±1.0 cm, respectively. Among the 4 adnomas, 3 （75.0%） cases were classified as branch type based on sonographic findings, and 2 were demonstrated as mural nodules in which no color signals was detected. Among the 8 adenocarcinomas, 5 （62.5%） cases were classifled as main duct type, and 3 （37.5%） as combined type. In 7 of the 8 adcnocarcinomas, mural nodules were detected within the dilated ducts or cysts of the lesions in which color flow signals were detected. Conclusions Transabdominal ultrasonography can reveal the pancreatic cystic lesions of IPMN as well as dilated pancreatic： ducts. Some characteristics should be noticed as suggesting the possibility of malignancy： clinical symptoms of pancreatic insufficiency, large tumor size, and mural nodules with color Doppler flow signals. Transabdominal ultrasonography could be a useful tool to help diagnose and make appropriate management of IPMN.
文摘This paper analyzes the correctly-expanded supersonic jet from a convergent-divergent axisymmetric nozzle by using numerical simulation of turbulent flow.And the calculated density distributions in this flow are compared with the present experimental data using rainbow schlieren deflectometry.The value of the density from the experimental data agrees well with the results calculated by this simulation.Therefore,the present method of the measurement using rainbow schlieren deflectometry is useful for the measurement of the density of the correctly-expanded supersonic jet.
基金supported by the National Natural Science Foundation of China(Nos.60808020 and 61078041)the National Science and Technology Support(No.2014BAH03F01)+1 种基金the Tianjin Research Program of Application Foundation and Advanced Technology(No.10JCYBJC07200)the Technology Program of Tianjin Municipal Education Commission(No.20130324)
文摘In the three-dimensional(3D) contour measurement,the phase shift profilometry(PSP) method is the most widely used one.However,the measurement speed of PSP is very low because of the multiple projections.In order to improve the measurement speed,color grating stripes are used for measurement in this paper.During the measurement,only one color sinusoidal fringe is projected on the measured object.Therefore,the measurement speed is greatly improved.Since there is coupling or interference phenomenon between the adjacent color grating stripes,a color correction method is used to improve the measurement results.A method for correcting nonlinear error of measurement system is proposed in this paper,and the sinusoidal property of acquired image after correction is better than that before correction.Experimental results show that with these correction methods,the measurement errors can be reduced.Therefore,it can support a good foundation for the high-precision 3D reconstruction.
