The objective of this study was to estimate the carbon storage capacity of Pinus densiflora stands using remotely sensed data by combining digital aerial photography with light detection and ranging(LiDAR) data.A digi...The objective of this study was to estimate the carbon storage capacity of Pinus densiflora stands using remotely sensed data by combining digital aerial photography with light detection and ranging(LiDAR) data.A digital canopy model(DCM),generated from the LiDAR data,was combined with aerial photography for segmenting crowns of individual trees.To eliminate errors in over and under-segmentation,the combined image was smoothed using a Gaussian filtering method.The processed image was then segmented into individual trees using a marker-controlled watershed segmentation method.After measuring the crown area from the segmented individual trees,the individual tree diameter at breast height(DBH) was estimated using a regression function developed from the relationship observed between the field-measured DBH and crown area.The above ground biomass of individual trees could be calculated by an image-derived DBH using a regression function developed by the Korea Forest Research Institute.The carbon storage,based on individual trees,was estimated by simple multiplication using the carbon conversion index(0.5),as suggested in guidelines from the Intergovernmental Panel on Climate Change.The mean carbon storage per individual tree was estimated and then compared with the field-measured value.This study suggested that the biomass and carbon storage in a large forest area can be effectively estimated using aerial photographs and LiDAR data.展开更多
A method of measuring the velocity of fast moving object by charge coupled device （CCD） shadow photograph system is developed. This system consists of high resolution orthogonal CCD cameras, time detecting device an...A method of measuring the velocity of fast moving object by charge coupled device （CCD） shadow photograph system is developed. This system consists of high resolution orthogonal CCD cameras, time detecting device and the pulsed laser which can generate two short laser pulses with adjustable interval more than 100 μs. Experiments are conducted to measure the velocity of the flying steel ball. The results show that the proposed velocity measurement is effective in modem ballistic measurement.展开更多
Objective To investigate the association of retinal vascular calibers with hyperuricemia in a middle‐aged and elderly population. Methods A cross‐sectional design was applied in this study and 869 participants aged ...Objective To investigate the association of retinal vascular calibers with hyperuricemia in a middle‐aged and elderly population. Methods A cross‐sectional design was applied in this study and 869 participants aged ≥40 years from a high‐risk group for diabetes were recruited. All participants received the anthropometrical measurements and laboratory tests. Retinal arteriolar and venular caliber of the participants were measured with a semi‐automated system. Hyperuricemia was defined as a serum uric acid level 420 μmol/L in men and 360 μmol/L in women. Linear regression models were used to assess the association of hyperuricemia with retinal vascular calibers. These models were additionally adjusted for age, central obesity, hypertension, dyslipidemia, weekly activity, smoking status, and education. Results Among the 869 participants, 133 （15.3%） suffered from hyperuricemia. The crude mean serum uric acid level was 312.3 μmol/L （Standard Deviation 79.5）; mean concentration was 355.0 μmol/L （SD 75.5） in male participants, and 288.0 μmol/L （SD 71.1） in female participants （age‐adjusted difference 58.1 μmol/L, 95% Confidence Internal 48.5, 67.6）. After adjusting for additional covariates, male participants with hyperuricemia had 3.77 μm （95% CI ‐0.46, 8.00） smaller arteriolar caliber and 6.20 μm （95% CI 0.36, 12.04） larger venule than those without hyperuricemia; the corresponding numbers among female participants were 1.57 μm （95% CI ‐1.07, 4.21） for retinal arteriolar caliber and 2.28 μm （95% CI ‐1.72, 6.27） for retinal venular caliber. Conclusion Hyperuricemia was associated with smaller retinal arteriolar caliber and larger venular caliber mainly in male participants in this study.展开更多
Condylar hyperplasia（CH） of human temporomandibular joint（TMJ） often occurs unilaterally, and causes occlusal disturbance and facial asymmetry. The purpose of this study was to compare the effects of high condylec...Condylar hyperplasia（CH） of human temporomandibular joint（TMJ） often occurs unilaterally, and causes occlusal disturbance and facial asymmetry. The purpose of this study was to compare the effects of high condylectomy with and without postsurgical orthodontic treatment. Forty patients were diagnosed as having active CH and treated with high condylectomy. Patients in group A（n=24） took the postsurgical orthodontic therapy immediately after surgery, and those in group B（n=16） did not take orthodontic therapy. For both groups, the mandibular ramus height on the affected side was decreased significantly after surgery. Orthodontic treatment promoted maxillary alveolar remodeling significantly by depressing alveolar bone of the affected side and increasing alveolar bone of the nonaffected side. Better improvement for facial midline deviations was observed in group A than in group B. In both groups, the condylar remodeling was observed and manifested by the smoothening of condylar surface and returning of condyle to normal position in glenoid fossa. It was concluded that high condylectomy in the treatment of active CH of TMJ improved the functional occlusion and facial aesthetic. Postsurgical orthodontic therapy could more effectively enhance maxillary alveolar and condylar remodeling, and more rapidly and meticulously establish the stable occlusal and normal position of condyle than the spontaneous remodeling.展开更多
Born in Sichuan Province,Mei Jian now lives in Canada.He graduated from the Com⁃puter Science Department of Sun Yat⁃sen Uni⁃versity in 1992 and worked as a programmer.Encouraged by friends,he began bird⁃watching in 20...Born in Sichuan Province,Mei Jian now lives in Canada.He graduated from the Com⁃puter Science Department of Sun Yat⁃sen Uni⁃versity in 1992 and worked as a programmer.Encouraged by friends,he began bird⁃watching in 2016 and developed a fondness for bird pho⁃tography.However,he found that he was occa⁃sionally uncertain about what species he had photographed.展开更多
Chongqing may be known as China’s cyberpunk capital,but local photographer Tu Ximeng is on a mission to capture the city’s more authentic moments—those often lost in the glowing haze of its futuristic facade.
大卫·普卢默是一位顶级的野生动物摄影师,一年中有几个月的时间他都在世界各地拍摄野生动物。1For David Plummer,wildlife and photography remained his passions.When he was 26,David took the leap to work towards becoming ...大卫·普卢默是一位顶级的野生动物摄影师,一年中有几个月的时间他都在世界各地拍摄野生动物。1For David Plummer,wildlife and photography remained his passions.When he was 26,David took the leap to work towards becoming a professional wildlife photographer.“I moved to Sussex and did various odd jobs-which included cleaning and care work-in order to survive while I built my contacts and work experience,”he says.“Being a volun-teer photographer for the Sussex Wildlife Trust was a turning point.”展开更多
基金the support of the ‘Public Applications Research of Satellite Data Project’ (Grant No. FR09662). provided by the Korea Aerospace Research Institutesupported by a research grant from the Korea Science and Engineering Foundation (KOSEF) (Grant No. A307-K001)
文摘The objective of this study was to estimate the carbon storage capacity of Pinus densiflora stands using remotely sensed data by combining digital aerial photography with light detection and ranging(LiDAR) data.A digital canopy model(DCM),generated from the LiDAR data,was combined with aerial photography for segmenting crowns of individual trees.To eliminate errors in over and under-segmentation,the combined image was smoothed using a Gaussian filtering method.The processed image was then segmented into individual trees using a marker-controlled watershed segmentation method.After measuring the crown area from the segmented individual trees,the individual tree diameter at breast height(DBH) was estimated using a regression function developed from the relationship observed between the field-measured DBH and crown area.The above ground biomass of individual trees could be calculated by an image-derived DBH using a regression function developed by the Korea Forest Research Institute.The carbon storage,based on individual trees,was estimated by simple multiplication using the carbon conversion index(0.5),as suggested in guidelines from the Intergovernmental Panel on Climate Change.The mean carbon storage per individual tree was estimated and then compared with the field-measured value.This study suggested that the biomass and carbon storage in a large forest area can be effectively estimated using aerial photographs and LiDAR data.
基金supported by the Project of National Key Laboratory (51453050105ZS33)
文摘A method of measuring the velocity of fast moving object by charge coupled device （CCD） shadow photograph system is developed. This system consists of high resolution orthogonal CCD cameras, time detecting device and the pulsed laser which can generate two short laser pulses with adjustable interval more than 100 μs. Experiments are conducted to measure the velocity of the flying steel ball. The results show that the proposed velocity measurement is effective in modem ballistic measurement.
基金supported by Science and Technology Commission of Shanghai Municipality (STCSM) and the Key Project of Health Bureau of Shanghai (Grant 04dz19501‐1 and 08GWZX0203 to Xin GAO)
文摘Objective To investigate the association of retinal vascular calibers with hyperuricemia in a middle‐aged and elderly population. Methods A cross‐sectional design was applied in this study and 869 participants aged ≥40 years from a high‐risk group for diabetes were recruited. All participants received the anthropometrical measurements and laboratory tests. Retinal arteriolar and venular caliber of the participants were measured with a semi‐automated system. Hyperuricemia was defined as a serum uric acid level 420 μmol/L in men and 360 μmol/L in women. Linear regression models were used to assess the association of hyperuricemia with retinal vascular calibers. These models were additionally adjusted for age, central obesity, hypertension, dyslipidemia, weekly activity, smoking status, and education. Results Among the 869 participants, 133 （15.3%） suffered from hyperuricemia. The crude mean serum uric acid level was 312.3 μmol/L （Standard Deviation 79.5）; mean concentration was 355.0 μmol/L （SD 75.5） in male participants, and 288.0 μmol/L （SD 71.1） in female participants （age‐adjusted difference 58.1 μmol/L, 95% Confidence Internal 48.5, 67.6）. After adjusting for additional covariates, male participants with hyperuricemia had 3.77 μm （95% CI ‐0.46, 8.00） smaller arteriolar caliber and 6.20 μm （95% CI 0.36, 12.04） larger venule than those without hyperuricemia; the corresponding numbers among female participants were 1.57 μm （95% CI ‐1.07, 4.21） for retinal arteriolar caliber and 2.28 μm （95% CI ‐1.72, 6.27） for retinal venular caliber. Conclusion Hyperuricemia was associated with smaller retinal arteriolar caliber and larger venular caliber mainly in male participants in this study.
文摘Condylar hyperplasia（CH） of human temporomandibular joint（TMJ） often occurs unilaterally, and causes occlusal disturbance and facial asymmetry. The purpose of this study was to compare the effects of high condylectomy with and without postsurgical orthodontic treatment. Forty patients were diagnosed as having active CH and treated with high condylectomy. Patients in group A（n=24） took the postsurgical orthodontic therapy immediately after surgery, and those in group B（n=16） did not take orthodontic therapy. For both groups, the mandibular ramus height on the affected side was decreased significantly after surgery. Orthodontic treatment promoted maxillary alveolar remodeling significantly by depressing alveolar bone of the affected side and increasing alveolar bone of the nonaffected side. Better improvement for facial midline deviations was observed in group A than in group B. In both groups, the condylar remodeling was observed and manifested by the smoothening of condylar surface and returning of condyle to normal position in glenoid fossa. It was concluded that high condylectomy in the treatment of active CH of TMJ improved the functional occlusion and facial aesthetic. Postsurgical orthodontic therapy could more effectively enhance maxillary alveolar and condylar remodeling, and more rapidly and meticulously establish the stable occlusal and normal position of condyle than the spontaneous remodeling.
文摘Born in Sichuan Province,Mei Jian now lives in Canada.He graduated from the Com⁃puter Science Department of Sun Yat⁃sen Uni⁃versity in 1992 and worked as a programmer.Encouraged by friends,he began bird⁃watching in 2016 and developed a fondness for bird pho⁃tography.However,he found that he was occa⁃sionally uncertain about what species he had photographed.
文摘Chongqing may be known as China’s cyberpunk capital,but local photographer Tu Ximeng is on a mission to capture the city’s more authentic moments—those often lost in the glowing haze of its futuristic facade.
文摘大卫·普卢默是一位顶级的野生动物摄影师,一年中有几个月的时间他都在世界各地拍摄野生动物。1For David Plummer,wildlife and photography remained his passions.When he was 26,David took the leap to work towards becoming a professional wildlife photographer.“I moved to Sussex and did various odd jobs-which included cleaning and care work-in order to survive while I built my contacts and work experience,”he says.“Being a volun-teer photographer for the Sussex Wildlife Trust was a turning point.”
