A monocular vision-based pose measurement system is provided for real-time measurement of a three-degree-of-freedom (3-DOF) air-bearing test-bed. Firstly, a circular plane cooperative target is designed. An image of...A monocular vision-based pose measurement system is provided for real-time measurement of a three-degree-of-freedom (3-DOF) air-bearing test-bed. Firstly, a circular plane cooperative target is designed. An image of a target fixed on the test-bed is then acquired. Blob analysis-based image processing is used to detect the object circles on the target. A fast algorithm (FCCSP) based on pixel statistics is proposed to extract the centers of object circles. Finally, pose measurements can be obtained when combined with the centers and the coordinate transformation relation. Experiments show that the proposed method is fast, accurate, and robust enough to satisfy the requirement of the pose measurement.展开更多
To the Editor:Posterior reversible encephalopathy syndrome (PRES) is a rare condition of the central nervous system (CNS).Clinically,it can present with headache,blurred vision,seizures,or coma.The diagnosis of PRES i...To the Editor:Posterior reversible encephalopathy syndrome (PRES) is a rare condition of the central nervous system (CNS).Clinically,it can present with headache,blurred vision,seizures,or coma.The diagnosis of PRES is based on the classic radiologic imaging studies at occipital and parietal lobes in the subcortical white matter,and sometimes in the cortex.Hypertensive encephalopathy,eclampsia,immunosuppressive agents,and cytotoxic drugs can cause PRES.A patient with PRES may recover without sequela after removal of the causative factors.Notably,uncertainty in diagnosis and delay in treatment would have probably aggravated CNS injuries or death.However,the underlying mechanism of the disease remains unclear and controversial.展开更多
基金This work is partially supported by the National Natural Science Foundation of China under Grant No. 11672290. The authors also gratefully acknowledge the helpful comments and suggestions of the reviewers, which have improved the presentation.
文摘A monocular vision-based pose measurement system is provided for real-time measurement of a three-degree-of-freedom (3-DOF) air-bearing test-bed. Firstly, a circular plane cooperative target is designed. An image of a target fixed on the test-bed is then acquired. Blob analysis-based image processing is used to detect the object circles on the target. A fast algorithm (FCCSP) based on pixel statistics is proposed to extract the centers of object circles. Finally, pose measurements can be obtained when combined with the centers and the coordinate transformation relation. Experiments show that the proposed method is fast, accurate, and robust enough to satisfy the requirement of the pose measurement.
基金This study was supported by the grants from the National Natural Science Foundation of China (No. 81801135)the Hunan provincial Science Foundation (No. 2017JJ3477).
文摘To the Editor:Posterior reversible encephalopathy syndrome (PRES) is a rare condition of the central nervous system (CNS).Clinically,it can present with headache,blurred vision,seizures,or coma.The diagnosis of PRES is based on the classic radiologic imaging studies at occipital and parietal lobes in the subcortical white matter,and sometimes in the cortex.Hypertensive encephalopathy,eclampsia,immunosuppressive agents,and cytotoxic drugs can cause PRES.A patient with PRES may recover without sequela after removal of the causative factors.Notably,uncertainty in diagnosis and delay in treatment would have probably aggravated CNS injuries or death.However,the underlying mechanism of the disease remains unclear and controversial.
基金Supported by National Natural Science Foundation of China (60575019), the National High Technology Research and Development Program of China (863 Program) (2006AA01Zl16), and Institute of Automation Chinese Academy of Sciences Innovation Fund For Young Scientists