In this paper the genus Ceratocallis Qiao and Zhang, Cerataphinae, Hormaphididae from China is described as new to science and the diagnosis of the new genus is provided. One new species, Ceratocallis camellis ...In this paper the genus Ceratocallis Qiao and Zhang, Cerataphinae, Hormaphididae from China is described as new to science and the diagnosis of the new genus is provided. One new species, Ceratocallis camellis Qiao and Zhang is described as new to science.展开更多
In order to improve the performance of estimating the fundamental matrix, a key problem arising in stereo vision, a novel method based on stripe constraints is presented. In contrast to traditional methods based on al...In order to improve the performance of estimating the fundamental matrix, a key problem arising in stereo vision, a novel method based on stripe constraints is presented. In contrast to traditional methods based on algebraic least-square algorithms, the proposed approach aims to minimize a cost function that is derived from the minimum radius of the Hough transform. In a structured-light system with a particular stripe code pattern, there are linear constraints that the points with the same code are on the same surface. Using the Hough transform, the pixels with the same code map to the Hough space, and the radius of the intersections can be defined as the evaluation function in the optimization progress. The global optimum solution of the fundamental matrix can be estimated using a Levenberg- Marquardt optimization iterative process based on the Hough transform radius. Results illustrate the validity of this algorithm, and prove that this method can obtain good performance with high efficiency.展开更多
In order to combine feature extraction operations with specific hyperspectral remote sensing information processing objectives,two aspects of feature extraction were explored. Based on clustering and decision tree alg...In order to combine feature extraction operations with specific hyperspectral remote sensing information processing objectives,two aspects of feature extraction were explored. Based on clustering and decision tree algorithm,spectral absorption index (SAI),continuum-removal and derivative spectral analysis were employed to discover characterized spectral features of different targets,and decision trees for identifying a specific class and discriminating different classes were generated. By combining support vector machine (SVM) classifier with different feature extraction strategies including principal component analysis (PCA),minimum noise fraction (MNF),grouping PCA,and derivate spectral analysis,the performance of feature extraction approaches in classification was evaluated. The results show that feature extraction by PCA and derivate spectral analysis are effective to OMIS (operational modular imaging spectrometer) image classification using SVM,and SVM outperforms traditional SAM and MLC classifiers for OMIS data.展开更多
The flapping-wing air vehicle(FWAV)is a kind of bio-inspired robot whose wings can flap up and down like bird and insect wings.A vision-based obstacle avoidance method for FWAVs is proposed in this paper.First,the Far...The flapping-wing air vehicle(FWAV)is a kind of bio-inspired robot whose wings can flap up and down like bird and insect wings.A vision-based obstacle avoidance method for FWAVs is proposed in this paper.First,the Farneback algorithm is used to calculate the optical flow field of the first-view video frames taken by the on-board image transmission camera.Based on the optical flow information,a fuzzy obstacle avoidance controller is then designed to generate the FWAV steering commands.Experimental results show that the proposed obstacle avoidance method can accurately identify obstacles and achieve obstacle avoidance for FWAVs.展开更多
In the laser displacement sensors measurement system,the laser beam direction is an important parameter.Particularly,the azimuth and pitch angles are the most important parameters to a laser beam.In this paper,based o...In the laser displacement sensors measurement system,the laser beam direction is an important parameter.Particularly,the azimuth and pitch angles are the most important parameters to a laser beam.In this paper,based on monocular vision,a laser beam direction measurement method is proposed.First,place the charge coupled device(CCD)camera above the base plane,and adjust and fix the camera position so that the optical axis is nearly perpendicular to the base plane.The monocular vision localization model is established by using circular aperture calibration board.Then the laser beam generating device is placed and maintained on the base plane at fixed position.At the same time a special target block is placed on the base plane so that the laser beam can project to the special target and form a laser spot.The CCD camera placed above the base plane can acquire the laser spot and the image of the target block clearly,so the two-dimensional(2D)image coordinate of the centroid of the laser spot can be extracted by correlation algorithm.The target is moved at an equal distance along the laser beam direction,and the spots and target images of each moving under the current position are collected by the CCD camera.By using the relevant transformation formula and combining the intrinsic parameters of the target block,the2D coordinates of the gravity center of the spot are converted to the three-dimensional(3D)coordinate in the base plane.Because of the moving of the target,the3D coordinates of the gravity center of the laser spot at different positions are obtained,and these3D coordinates are synthesized into a space straight line to represent the laser beam to be measured.In the experiment,the target parameters are measured by high-precision instruments,and the calibration parameters of the camera are calibrated by a high-precision calibration board to establish the corresponding positioning model.The measurement accuracy is mainly guaranteed by the monocular vision positioning accuracy and the gravity center extraction accuracy.The experimental results show the maximum error of the angle between laser beams reaches to0.04°and the maximum error of beam pitch angle reaches to0.02°.展开更多
This letter addresses several key issues in the process of model-based optical metrology, including three dimensional (3D) sensing, calibration, registration and fusion of range images, geometric representation, and v...This letter addresses several key issues in the process of model-based optical metrology, including three dimensional (3D) sensing, calibration, registration and fusion of range images, geometric representation, and visualization of reconstructed 3D model by taking into account the shape measurement of 3D complex structures,and some experimental results are presented.展开更多
For conventional optical polarization imaging of underwater target,the polarization degree of backscatter should be pre-measured by averaging the pixel intensities in the no target region of the polarization images,an...For conventional optical polarization imaging of underwater target,the polarization degree of backscatter should be pre-measured by averaging the pixel intensities in the no target region of the polarization images,and the polarization property of the target is assumed to be completely depolarized.When the scattering background is unseen in the field of view or the target is polarized,conventional method is helpless in detecting the target.An improvement is to use lots of co-polarization and cross polarization detection components.We propose a polarization subtraction method to estimate depolarization property of the scattering noise and target signal.And experiment in a quartz cuvette container is performed to demonstrate the effectiveness of the proposed method.The results show that the proposed method can work without scattering background reference,and further recover the target along with smooth surface for polarization preserving response.This study promotes the development of optical polarization imaging systems in underwater environments.展开更多
Dengue vector is responsible for millions of deaths every year and has caused disastrous impacts on health systems. The continuous use of chemical insecticides, such as carbamates, pyrethroids and organophosphates gen...Dengue vector is responsible for millions of deaths every year and has caused disastrous impacts on health systems. The continuous use of chemical insecticides, such as carbamates, pyrethroids and organophosphates generates resistant populations of the mosquito, therefore, new control methods must be investigated. The joint action of the population and guidelines for preventing the reproduction of the mosquito associated with the use of photoactivatable insecticides can be the alternative for the control of epidemiological outbreaks in affected regions. In this study, the photo-larvicidal activity of Photogem^（PG）, a derivative of hematoporphyrin, was investigated against 2nd-early 3rd instar of Aedes aegypti larvae （Diptera： Culicidae） under different lighting conditions （artificial lighting system and sunlight）. The dynamics of PG accumulation was characterized by CLSM （confocal laser scanning microscopy） and total time PG eliminationin solution was investigated by ultraviolet-visible spectrophotometry. The maximum photo-activity of PG was observed in 0.5 h under sunlight exposure which achieved 100% larval mortality. Fluorescence images showed a uniform distribution of PG along the digestive tract. PG remained stable in the sunlight for 48 h and in an artificial lighting system for longer periods, therefore, it can be used for the control ofAedes aegypti larvae as a new alternative to chemical insecticides. The method is considered environmentally friendly due to its rapid degradation in the presence of light. Further studies are required, so that the potential of the technique can be explored in real breeding places.展开更多
The dexterous hand is equiped with the flexible fiber as the optic sensor for recognition and identification of objects structured and non-structured environment.This simple and inexpensive method for object recogniti...The dexterous hand is equiped with the flexible fiber as the optic sensor for recognition and identification of objects structured and non-structured environment.This simple and inexpensive method for object recognition based on the optical fiber is presented in this paper.展开更多
Objective To analyze the effects of Dan Huang Ming Mu Recipe(DHMMR)(a pharmaceutical preparation from herbs and having the function of replenishing vital essence,removing heat,promoting blood circulation and excreting...Objective To analyze the effects of Dan Huang Ming Mu Recipe(DHMMR)(a pharmaceutical preparation from herbs and having the function of replenishing vital essence,removing heat,promoting blood circulation and excreting pathogenic water) on diabetic retinopathy(DR) after retinal laser photocoagulation through regulating the expression of vascular endothelial growth factor(VEGF) and pigment epithelium-derived factor(PEDF).Methods Forty male Brown Norway(BN) rats were randomly divided into blank group(group A,10 BN rats) and model group(30 BN rats).DR models were induced by 40 mg/kg streptozotocin(STZ) and the body weight and blood glucose of rats were monitored.After 12-week injection,fluorescein fundus angiography(FFA) and histopathological examination were detected to confirm the successful establishment of DR models.Subsequently,the right eyes of model group rats were conducted retinal laser photocoagulation with the left eyes having no retinal laser photocoagulation and rats of the model group were randomly divided into group B(the model control group),group C(the positive control group),and group D(the DHMMR group),with 10 rats in each group.Rats of the group A and the group B were given vehicle,and the group C were given calcium dobesilate suspension by gavage,and the group D were given DHMMR by gavage.After 4-week gavage,FFA was carried out to observe the fundus microvascular change.Then,the rats were sacrificed to do histopathological examinations and the serum levels of P-selectin,cAMP,cGMP,and the relative expression of the protein of VEGF and PEDF in retina were detected.Results After 12-week STZ injection,the blood glucose of the model group were pronouncedly higher than the blank group(P < 0.01).Fundus micro-hemangioma changes were observed in the rats of the model group through FFA,and the rats of the blank group did not see any changes.The pictures of HE staining showed that the retinal structure of the model group was more disordered than the blank group.After 4-week gavage,treatments with DHMMR showed dramatic reduction of serum levels of Pselectin,cAMP and cGMP compared with the group B(P < 0.01).FFA and histopathological examinations of DHMMR-treated rats revealed significantly suppression of retinal edema,fundus microvascular destruction and retinal destruction distinguishing from the group B.And the relative expression of VEGF protein of the group D and the group A was markedly lower than that of the group B(P < 0.01).The relative expression of PEDF protein of the group D and the group A was dramatically higher than that of the group B to the contrary(P < 0.01).Conclusions DHMMR demonstrates pronounced suppressive effects on the progression of DR after retinal laser photocoagulation,through down-regulating VEGF and upregulating PEDF.展开更多
文摘In this paper the genus Ceratocallis Qiao and Zhang, Cerataphinae, Hormaphididae from China is described as new to science and the diagnosis of the new genus is provided. One new species, Ceratocallis camellis Qiao and Zhang is described as new to science.
文摘In order to improve the performance of estimating the fundamental matrix, a key problem arising in stereo vision, a novel method based on stripe constraints is presented. In contrast to traditional methods based on algebraic least-square algorithms, the proposed approach aims to minimize a cost function that is derived from the minimum radius of the Hough transform. In a structured-light system with a particular stripe code pattern, there are linear constraints that the points with the same code are on the same surface. Using the Hough transform, the pixels with the same code map to the Hough space, and the radius of the intersections can be defined as the evaluation function in the optimization progress. The global optimum solution of the fundamental matrix can be estimated using a Levenberg- Marquardt optimization iterative process based on the Hough transform radius. Results illustrate the validity of this algorithm, and prove that this method can obtain good performance with high efficiency.
基金Projects 40401038 and 40871195 supported by the National Natural Science Foundation of ChinaNCET-06-0476 by the Program for New Century Excellent Talents in University20070290516 by the Specialized Research Fund for the Doctoral Program of Higher Education
文摘In order to combine feature extraction operations with specific hyperspectral remote sensing information processing objectives,two aspects of feature extraction were explored. Based on clustering and decision tree algorithm,spectral absorption index (SAI),continuum-removal and derivative spectral analysis were employed to discover characterized spectral features of different targets,and decision trees for identifying a specific class and discriminating different classes were generated. By combining support vector machine (SVM) classifier with different feature extraction strategies including principal component analysis (PCA),minimum noise fraction (MNF),grouping PCA,and derivate spectral analysis,the performance of feature extraction approaches in classification was evaluated. The results show that feature extraction by PCA and derivate spectral analysis are effective to OMIS (operational modular imaging spectrometer) image classification using SVM,and SVM outperforms traditional SAM and MLC classifiers for OMIS data.
基金This work was supported in part by the National Natural Science Foundation of China(Nos.61803025,62073031)the Interdisciplinary Research Project for Young Teachers of USTB(Fundamental Research Funds for the Central Universities)(No.FRF-IDRY-19010)the Beijing Top Discipline for Artificial Intelligent Science and Engineering,University of Science and Technology Beijing.
文摘The flapping-wing air vehicle(FWAV)is a kind of bio-inspired robot whose wings can flap up and down like bird and insect wings.A vision-based obstacle avoidance method for FWAVs is proposed in this paper.First,the Farneback algorithm is used to calculate the optical flow field of the first-view video frames taken by the on-board image transmission camera.Based on the optical flow information,a fuzzy obstacle avoidance controller is then designed to generate the FWAV steering commands.Experimental results show that the proposed obstacle avoidance method can accurately identify obstacles and achieve obstacle avoidance for FWAVs.
基金National Science and Technology Major Project of China(No.2016ZX04003001)Tianjin Research Program of Application Foundation and Advanced Technology(No.14JCZDJC39700)
文摘In the laser displacement sensors measurement system,the laser beam direction is an important parameter.Particularly,the azimuth and pitch angles are the most important parameters to a laser beam.In this paper,based on monocular vision,a laser beam direction measurement method is proposed.First,place the charge coupled device(CCD)camera above the base plane,and adjust and fix the camera position so that the optical axis is nearly perpendicular to the base plane.The monocular vision localization model is established by using circular aperture calibration board.Then the laser beam generating device is placed and maintained on the base plane at fixed position.At the same time a special target block is placed on the base plane so that the laser beam can project to the special target and form a laser spot.The CCD camera placed above the base plane can acquire the laser spot and the image of the target block clearly,so the two-dimensional(2D)image coordinate of the centroid of the laser spot can be extracted by correlation algorithm.The target is moved at an equal distance along the laser beam direction,and the spots and target images of each moving under the current position are collected by the CCD camera.By using the relevant transformation formula and combining the intrinsic parameters of the target block,the2D coordinates of the gravity center of the spot are converted to the three-dimensional(3D)coordinate in the base plane.Because of the moving of the target,the3D coordinates of the gravity center of the laser spot at different positions are obtained,and these3D coordinates are synthesized into a space straight line to represent the laser beam to be measured.In the experiment,the target parameters are measured by high-precision instruments,and the calibration parameters of the camera are calibrated by a high-precision calibration board to establish the corresponding positioning model.The measurement accuracy is mainly guaranteed by the monocular vision positioning accuracy and the gravity center extraction accuracy.The experimental results show the maximum error of the angle between laser beams reaches to0.04°and the maximum error of beam pitch angle reaches to0.02°.
基金This work is supported by National Natural Science Foundationof China.(Grant No. 60275012)Natural Science Research Foundof Higher Education in Guangdong Province (Grant No. 04Z010)+1 种基金the Natural Science Foundation of Guangdong Province (GranNo. 06028584) the Research Project of Science & Technol-ogy from Shenzhen Government (Grant No.200619).
文摘This letter addresses several key issues in the process of model-based optical metrology, including three dimensional (3D) sensing, calibration, registration and fusion of range images, geometric representation, and visualization of reconstructed 3D model by taking into account the shape measurement of 3D complex structures,and some experimental results are presented.
基金National Natural Science Foundation of China(Nos.11847069,11847127)Science Foundation of North University of China(No.XJJ20180030)。
文摘For conventional optical polarization imaging of underwater target,the polarization degree of backscatter should be pre-measured by averaging the pixel intensities in the no target region of the polarization images,and the polarization property of the target is assumed to be completely depolarized.When the scattering background is unseen in the field of view or the target is polarized,conventional method is helpless in detecting the target.An improvement is to use lots of co-polarization and cross polarization detection components.We propose a polarization subtraction method to estimate depolarization property of the scattering noise and target signal.And experiment in a quartz cuvette container is performed to demonstrate the effectiveness of the proposed method.The results show that the proposed method can work without scattering background reference,and further recover the target along with smooth surface for polarization preserving response.This study promotes the development of optical polarization imaging systems in underwater environments.
文摘Dengue vector is responsible for millions of deaths every year and has caused disastrous impacts on health systems. The continuous use of chemical insecticides, such as carbamates, pyrethroids and organophosphates generates resistant populations of the mosquito, therefore, new control methods must be investigated. The joint action of the population and guidelines for preventing the reproduction of the mosquito associated with the use of photoactivatable insecticides can be the alternative for the control of epidemiological outbreaks in affected regions. In this study, the photo-larvicidal activity of Photogem^（PG）, a derivative of hematoporphyrin, was investigated against 2nd-early 3rd instar of Aedes aegypti larvae （Diptera： Culicidae） under different lighting conditions （artificial lighting system and sunlight）. The dynamics of PG accumulation was characterized by CLSM （confocal laser scanning microscopy） and total time PG eliminationin solution was investigated by ultraviolet-visible spectrophotometry. The maximum photo-activity of PG was observed in 0.5 h under sunlight exposure which achieved 100% larval mortality. Fluorescence images showed a uniform distribution of PG along the digestive tract. PG remained stable in the sunlight for 48 h and in an artificial lighting system for longer periods, therefore, it can be used for the control ofAedes aegypti larvae as a new alternative to chemical insecticides. The method is considered environmentally friendly due to its rapid degradation in the presence of light. Further studies are required, so that the potential of the technique can be explored in real breeding places.
文摘The dexterous hand is equiped with the flexible fiber as the optic sensor for recognition and identification of objects structured and non-structured environment.This simple and inexpensive method for object recognition based on the optical fiber is presented in this paper.
基金the funding support from the Provincial Natural Science Foundation General Program(No.2015JJ2109)Hunan Province Graduate Student Research Innovation Program(No.CX2018B473)+7 种基金Hunan Traditional Chinese Medicine Scientific Research Program(NO.201463 and NO.2017141)Key Scientific Research Project of Hunan Administration of Traditional Chinese Medicine(NO.201917)University-level Scientific Research Projects of Hunan University of Chinese Medicine(NO.2017029 and NO.2018XJJJ31)The Domestic Firstclass Discipline Construction Project of Chinese Medicine of Hunan University of Chinese MedicineCentral Finance Supported Local High School Construction ProjectState Administration of Traditional Chinese Medicine Ophthalmology Key Discipline Construction ProjectHunan Province Traditional Chinese Medicine Facial Feature Key Discipline Construction ProjectHunan Engineering Technology Research Center for the Prevention and Treatment of Otorhinolaryngologic Diseases and Protection of Visual Function with Chinese Medicine,Hunan Provincial Key Laboratory for the Prevention and Treatment of Ophthalmology and Otolaryngology Diseases with Traditional Chinese Medicine
文摘Objective To analyze the effects of Dan Huang Ming Mu Recipe(DHMMR)(a pharmaceutical preparation from herbs and having the function of replenishing vital essence,removing heat,promoting blood circulation and excreting pathogenic water) on diabetic retinopathy(DR) after retinal laser photocoagulation through regulating the expression of vascular endothelial growth factor(VEGF) and pigment epithelium-derived factor(PEDF).Methods Forty male Brown Norway(BN) rats were randomly divided into blank group(group A,10 BN rats) and model group(30 BN rats).DR models were induced by 40 mg/kg streptozotocin(STZ) and the body weight and blood glucose of rats were monitored.After 12-week injection,fluorescein fundus angiography(FFA) and histopathological examination were detected to confirm the successful establishment of DR models.Subsequently,the right eyes of model group rats were conducted retinal laser photocoagulation with the left eyes having no retinal laser photocoagulation and rats of the model group were randomly divided into group B(the model control group),group C(the positive control group),and group D(the DHMMR group),with 10 rats in each group.Rats of the group A and the group B were given vehicle,and the group C were given calcium dobesilate suspension by gavage,and the group D were given DHMMR by gavage.After 4-week gavage,FFA was carried out to observe the fundus microvascular change.Then,the rats were sacrificed to do histopathological examinations and the serum levels of P-selectin,cAMP,cGMP,and the relative expression of the protein of VEGF and PEDF in retina were detected.Results After 12-week STZ injection,the blood glucose of the model group were pronouncedly higher than the blank group(P < 0.01).Fundus micro-hemangioma changes were observed in the rats of the model group through FFA,and the rats of the blank group did not see any changes.The pictures of HE staining showed that the retinal structure of the model group was more disordered than the blank group.After 4-week gavage,treatments with DHMMR showed dramatic reduction of serum levels of Pselectin,cAMP and cGMP compared with the group B(P < 0.01).FFA and histopathological examinations of DHMMR-treated rats revealed significantly suppression of retinal edema,fundus microvascular destruction and retinal destruction distinguishing from the group B.And the relative expression of VEGF protein of the group D and the group A was markedly lower than that of the group B(P < 0.01).The relative expression of PEDF protein of the group D and the group A was dramatically higher than that of the group B to the contrary(P < 0.01).Conclusions DHMMR demonstrates pronounced suppressive effects on the progression of DR after retinal laser photocoagulation,through down-regulating VEGF and upregulating PEDF.
