Blood pressure is an important physiological parameter to reflect human vital signs.In order to achieve the non-contact dynamic blood pressure acquisition based on ordinary optical camera,a theoretical understanding o...Blood pressure is an important physiological parameter to reflect human vital signs.In order to achieve the non-contact dynamic blood pressure acquisition based on ordinary optical camera,a theoretical understanding of the functional relationship between blood pressure and pulse wave signal conduction time.And through imaging photoelectric plethysmography(IPPG),pulse wave signal conduction time of forehead and hand was obtained with ordinary optical camera.First,the pulse wave conduction time was obtained by recording the video with an ordinary optical camera.Second,real-time blood pressure values were collected.Finally,based on the relationship between blood pressure and pulse wave conduction time,a non-contact blood pressure measurement prediction model was obtained through neural network fitting.So that non-contact blood pressure measurement with optical camera could be completed.The method in this paper has several advantages,such as low requirements on measuring equipment,low cost,and simple operation.It can let people get rid of the discomfort caused by measuring equipment such as cuff and can measure blood pressure at any time.The predicted blood pressure results were compared with an Omron wrist electronic sphygmomanometer.The calculated error of systolic blood pressure is-9.28%~3.16%,and the error of diastolic blood pressure is-9.84~4.35%.展开更多
自变量筛选是定量光谱分析领域的研究热点,简便且高效的自变量筛选方法不但可以降低分析计算量,提高分析精度,同时还可以减轻对仪器光谱分辨能力的依赖,降低分析成本。波长筛选也是光谱法无创血液成分检测研究的重要环节。动态光谱理论...自变量筛选是定量光谱分析领域的研究热点,简便且高效的自变量筛选方法不但可以降低分析计算量,提高分析精度,同时还可以减轻对仪器光谱分辨能力的依赖,降低分析成本。波长筛选也是光谱法无创血液成分检测研究的重要环节。动态光谱理论为血液无创检测提供了极佳的思路,但长期局限于使用宽带光源和高分辨率的光谱仪器,分析中需要大量波长限制了动态光谱法的进一步发展。为了去除冗余信息,使检测走向低成本化和集成化,提出了基于变量投影重要性(variable importance in projection,VIP)分析的波长筛选方法。通过分析PLS模型中各维自变量对因变量的解释能力,从而剔除重要性较低的变量保留解释能力强的波长。以232例受试者的临床实验数据为基础,以血红蛋白含量为分析对象,经投影重要性分析后将波长数由586降至64,波长筛选后血红蛋白预测模型的测试集平均相对误差(MREP)为1.82%,使用了极少的波长便可得到满意的结果;结合Bootstrap方法对模型进行显著性检验后验证了波长变量的解释能力。首次指出了使用动态光谱法检测血红蛋白的敏感波长带。基于投影重要性分析的波长筛选迈出了动态光谱走向实用的重要一步,为实现低成本在线分析打下了基础,同时也为其他领域的光谱分析提供了重要的参考和新的思路。展开更多
Describe some new fully automatic instruments for the measurements of the blood capillary pressure (Pcap) and arterial elastic properties in human fingers using a photoelectric plethysmographic technique, With these i...Describe some new fully automatic instruments for the measurements of the blood capillary pressure (Pcap) and arterial elastic properties in human fingers using a photoelectric plethysmographic technique, With these instruments, the value of Pcap was in good agreement with those reported by other investigators, the arterial elastic properties in human fingers have been successfully measured. The measurements of Pcap and arterial elasticity are now required in clinics because they provide useful and important information for evaluating vascular haemodynamics.展开更多
基金The work of this paper is supported by the National Natural Science Foundation of China under Grant No.61572038,the Innovation Project Foundation NCUT.
文摘Blood pressure is an important physiological parameter to reflect human vital signs.In order to achieve the non-contact dynamic blood pressure acquisition based on ordinary optical camera,a theoretical understanding of the functional relationship between blood pressure and pulse wave signal conduction time.And through imaging photoelectric plethysmography(IPPG),pulse wave signal conduction time of forehead and hand was obtained with ordinary optical camera.First,the pulse wave conduction time was obtained by recording the video with an ordinary optical camera.Second,real-time blood pressure values were collected.Finally,based on the relationship between blood pressure and pulse wave conduction time,a non-contact blood pressure measurement prediction model was obtained through neural network fitting.So that non-contact blood pressure measurement with optical camera could be completed.The method in this paper has several advantages,such as low requirements on measuring equipment,low cost,and simple operation.It can let people get rid of the discomfort caused by measuring equipment such as cuff and can measure blood pressure at any time.The predicted blood pressure results were compared with an Omron wrist electronic sphygmomanometer.The calculated error of systolic blood pressure is-9.28%~3.16%,and the error of diastolic blood pressure is-9.84~4.35%.
文摘自变量筛选是定量光谱分析领域的研究热点,简便且高效的自变量筛选方法不但可以降低分析计算量,提高分析精度,同时还可以减轻对仪器光谱分辨能力的依赖,降低分析成本。波长筛选也是光谱法无创血液成分检测研究的重要环节。动态光谱理论为血液无创检测提供了极佳的思路,但长期局限于使用宽带光源和高分辨率的光谱仪器,分析中需要大量波长限制了动态光谱法的进一步发展。为了去除冗余信息,使检测走向低成本化和集成化,提出了基于变量投影重要性(variable importance in projection,VIP)分析的波长筛选方法。通过分析PLS模型中各维自变量对因变量的解释能力,从而剔除重要性较低的变量保留解释能力强的波长。以232例受试者的临床实验数据为基础,以血红蛋白含量为分析对象,经投影重要性分析后将波长数由586降至64,波长筛选后血红蛋白预测模型的测试集平均相对误差(MREP)为1.82%,使用了极少的波长便可得到满意的结果;结合Bootstrap方法对模型进行显著性检验后验证了波长变量的解释能力。首次指出了使用动态光谱法检测血红蛋白的敏感波长带。基于投影重要性分析的波长筛选迈出了动态光谱走向实用的重要一步,为实现低成本在线分析打下了基础,同时也为其他领域的光谱分析提供了重要的参考和新的思路。
文摘Describe some new fully automatic instruments for the measurements of the blood capillary pressure (Pcap) and arterial elastic properties in human fingers using a photoelectric plethysmographic technique, With these instruments, the value of Pcap was in good agreement with those reported by other investigators, the arterial elastic properties in human fingers have been successfully measured. The measurements of Pcap and arterial elasticity are now required in clinics because they provide useful and important information for evaluating vascular haemodynamics.
