Human body communication(HBC) is a promising near-field communication(NFC) method emerging in recent years. But existing theoretical models of HBC are too simple to simulate the wave propagation on human body. In this...Human body communication(HBC) is a promising near-field communication(NFC) method emerging in recent years. But existing theoretical models of HBC are too simple to simulate the wave propagation on human body. In this work, in order to clarify the propagation mechanism of electromagnetic wave on human body, a surface waveguide HBC theoretical model based on stratified media cylinder is presented. A numerical model analyzed by finite element method(FEM) is used for comparing and validating the theoretical model. Finally, results of theoretical and numerical models from 80 MHz to 200 MHz agree fairly well, which means that theoretical model can characterize accurate propagation mechanism of HBC signal. Meanwhile, attenuation constants derived from two kinds of models are within the range from 1.64 to 3.37, so that HBC signal can propagate effectively on human body. The propagation mechanism derived from the theoretical model is useful to provide design information for the transmitter and the modeling of the propagation channel in HBC.展开更多
为了提高多目标异常行为的识别精度,提出红外图像序列中多运动目标异常行为识别方法。对红外图像展开一次引导滤波,得到其信息细节,对上述图像再次展开引导滤波,得到二次引导滤波后信息细节,同时和一次引导滤波后信息细节作差,并把上述...为了提高多目标异常行为的识别精度,提出红外图像序列中多运动目标异常行为识别方法。对红外图像展开一次引导滤波,得到其信息细节,对上述图像再次展开引导滤波,得到二次引导滤波后信息细节,同时和一次引导滤波后信息细节作差,并把上述获取的图像细节信息与输入图像展开加权求和,得到增强后的红外图像。将人体骨骼关节点作为依据,分别获取关节速度、运动员重心以及关节角度特征,构建双向长短时记忆网络(Bidirectional Long Short-Term Memory Network,Bi-LSTM),并将上述特征输入该模型内,实现多运动目标异常行为识别。经实验验证得出,所提方法对红外图像的增强效果好,多目标异常行为的识别精度高。展开更多
基金Project(2009ZX01031-001-007-2)supported by the National Science and Technology Major Project,China
文摘Human body communication(HBC) is a promising near-field communication(NFC) method emerging in recent years. But existing theoretical models of HBC are too simple to simulate the wave propagation on human body. In this work, in order to clarify the propagation mechanism of electromagnetic wave on human body, a surface waveguide HBC theoretical model based on stratified media cylinder is presented. A numerical model analyzed by finite element method(FEM) is used for comparing and validating the theoretical model. Finally, results of theoretical and numerical models from 80 MHz to 200 MHz agree fairly well, which means that theoretical model can characterize accurate propagation mechanism of HBC signal. Meanwhile, attenuation constants derived from two kinds of models are within the range from 1.64 to 3.37, so that HBC signal can propagate effectively on human body. The propagation mechanism derived from the theoretical model is useful to provide design information for the transmitter and the modeling of the propagation channel in HBC.
文摘为了提高多目标异常行为的识别精度,提出红外图像序列中多运动目标异常行为识别方法。对红外图像展开一次引导滤波,得到其信息细节,对上述图像再次展开引导滤波,得到二次引导滤波后信息细节,同时和一次引导滤波后信息细节作差,并把上述获取的图像细节信息与输入图像展开加权求和,得到增强后的红外图像。将人体骨骼关节点作为依据,分别获取关节速度、运动员重心以及关节角度特征,构建双向长短时记忆网络(Bidirectional Long Short-Term Memory Network,Bi-LSTM),并将上述特征输入该模型内,实现多运动目标异常行为识别。经实验验证得出,所提方法对红外图像的增强效果好,多目标异常行为的识别精度高。
