首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
This paper presents a quantitative method for automatic identification of human pulse signals. The idea is to start with the extraction of characteristic parameters and then to construct the recognition model based on Bayesian networks. To identify depth, frequency and rhythm, several parameters are proposed. To distinguish the strength and shape, which cannot be represented by one or several parameters and are hard to recognize, the main time-domain feature parameters are computed based on the feature points of the pulse signal. Then the extracted parameters are taken as the input and five models for automatic pulse signal identification are constructed based on Bayesian networks. Experimental results demonstrate that the method is feasible and effective in recognizing depth, frequency, rhythm, strength and shape of pulse signals, which can be expected to facilitate the modernization of pulse diagnosis.  相似文献   

2.
提出了一种基于多结构元素的数学形态学图象角点检测方法.通过构造多种结构元素分别对图像进行腐蚀和相关的数学形态学运算,得到了图像的各种角点,然后在把这些角点合并起来便得到了图像的所有角点.实验结果表明本文算法能够准确的找到图像的角点,而且对噪声有很好的抑制作用.  相似文献   

3.
针对现行永磁同步电机初始位置定位方法的缺陷,提出一种基于电压空间矢量原理生成高分辨率的脉冲电压,并结合复合式增量编码器的uVw信号,自动检测霍尔信号进行永磁同步电机初始位置定位的智能方法。通过自主开发的以数字信号处理器为核心的实验平台进行了功能验证,实现了永磁同步电机无机械冲击和最大转矩启动。  相似文献   

4.
为提高局放信号检测的准确度,确保电力设备故障诊断的有效性和可靠性,本利用连续小波变换对背景噪声较强的的局放信号进行多尺度分解,在某些尺度下,使局放信号明显增强,用阀值比较可以有效地检测并消除噪声干扰。实验结果表明,只要选取合适的小波函数就能有效地抑制噪声干扰并完成对局放信号的检测和特征提取。  相似文献   

5.
The PP intervals of pulse main peaks from healthy and unhealthy people(arrhythmia) have different nonlinear char-acteristics. In this paper,the extraction of PP intervals of pulse main peaks is achieved by picking up P peaks of pulse wave with wavelet transform. Furthermore,several nonlinear parameters(correlative dimensions,maximum Lyapunov exponents,com-plexity and approximate entropy) of the PP intervals of pulse main peaks extracted from normal and unhealthy pulse signals are calculated,with the results showing that these nonlinear parameters calculated from the main wave interval signals are helpful for analyzing human's health state and diagnosing heart diseases.  相似文献   

6.
基于脉搏检测与无线传输系统的设计   总被引:1,自引:0,他引:1  
结合嵌入式与无线通信技术,提出了一种基于嵌入式无线脉搏传输与检测系统的方法。该方法能对人体脉搏波动态参数进行采集和分析,主要利用下位机通过SC0073动态微压传感器提取脉搏信号,通过嵌入式Atmega8515处理器对脉搏信号进行处理,然后通过无线收发模块NRF905远距离无线传送,并在电脑上采用LabVIEW界面直观的显示人体检测部位温度、脉搏波形信号的时域特性与频域特性,还能够通过开启远程监控系统对人体脉搏的数据进行分析,可以使医生完成远程在线诊断。  相似文献   

7.
脉冲调制是用采样信号的采样值去控制脉冲序列信号的参数。脉冲序列信号有4个参数:脉冲幅度、脉冲宽度、脉冲位置、脉冲频率。因此脉冲模拟调制有4种方式:脉冲幅度调制(PAM)、脉冲宽度调制(PWM)、脉冲频率调制(PFM)、脉冲位置调制(PPM)。这几种调制方式的信号产生和解调原理与实现方法有很多相似之处,本文就PPM信号的产生与解调方法进行分析。  相似文献   

8.
Cognitive styles have been regarded as a crucial factor that affects the effectiveness of web-based learning (WBL). Previous research indicated that educational settings that match with students' cognitive styles can enhance students' learning performance, which is, however, linked to their emotion. Various physiological signals can be applied to measure emotion but the pulse is perhaps the most effective indicator. Thus, we conduct an exploratory research, which looks for a link between emotion and the matching/mismatching instructional approach with the condition of cognitive styles through a continuous pulse rate monitoring. The matching/mismatching instructional approach was delivered via a WBL system, which includes an index version and map version. The pulses of individual learners are collected by using a non-intrusive sensor. Our results indicate that the matching condition enables learners to feel more positive emotions than the mismatching condition, and is also linked to better learning performance.  相似文献   

9.
针对风力发电机关键部件齿轮箱故障频率高、诊断难的问题,开发了包含传统时频域分析和现代分析模块的故障诊断系统。该系统对所采集的振动信号进行了小波去噪、小波包分解并重构后得到各频段能量占比的特征向量,将该特征向量输入到Back Propagation(BP)神经网络模型进行振动信号与正常或各故障状态之间映射,从而智能识别运行状态。应用Matlab和Labview开发系统,输入齿轮箱的4种典型运行状态进行验证,结果表明,所设计的系统可较好地对风机齿轮箱的故障进行诊断。  相似文献   

10.
基于嵌入式ATmega8515的脉搏检测与无线传输系统研究   总被引:1,自引:0,他引:1  
结合嵌入式与无线传输等相关技术,提出了一种基于嵌入式的无线脉搏传输与检测系统.该系统可以对人体脉搏波参数进行采集分析,并在PC机上采用LabVIEW界面显示人体手腕温度、脉搏波形信号波形和频率.同时,还能够通过开启远程监控系统对人体脉搏的数据进行分析,方便医生远程诊断.  相似文献   

11.
In order to detect and assess the muscle fatigue state with the surface electromyography(sEMG) characteristic parameters,this paper carried out a series of isometric contraction experiments to induce the fatigue on the forearm muscles from four subjects,and recorded the sEMG signals of the flexor carpi ulnaris.sEMG's median frequency(MDF) and mean frequency(MF) were extracted by short term Fourier transform(STFT),and the root mean square(RMS) of wavelet coefficients in the frequency band of 5—45 Hz was obtained by continuous wavelet transform(CWT).The results demonstrate that both MDF and MF show downward trends within 1 min; however,RMS shows an upward trend within the same time.The three parameters are closely correlated with absolute values of mean correlation coefficients greater than 0.8.It is suggested that the three parameters above can be used as reliable indicators to evaluate the level of muscle fatigue during isometric contractions.  相似文献   

12.
利用多模光纤缠绕钢绳式传感阵列网络,对智能材料与结构的受力,应变等状态参量进行监测和估计,并采用光时域反射(OTDR)技术实时处理并行分布式传感信号,给出了识别结果。  相似文献   

13.
Neurochip based on light-addressable potentiometric sensor(LAPS),whose sensing elements are excitable cells,can monitor electrophysiological properties of cultured neuron networks with cellular signals well analyzed.Here we report a kind of neurochip with rat pheochromocytoma(PC12) cells hybrid with LAPS and a method of de-noising signals based on wavelet transform.Cells were cultured on LAPS for several days to form networks,and we then used LAPS system to detect the extracellular potentials with signals d...  相似文献   

14.
区域是幼儿园环境的重要组成部分,在班级里我们会根据幼儿的年龄特点和兴趣爱好,开辟多种多样的区角,"阅读区"是必不可少的一角。利用好阅读区,既可激发幼儿说的兴趣,又可有效地发展幼儿的语言,达到事半功倍的效果。但随着多样区域活动的开展,孩子们更加喜欢形形色色的玩具,对阅读区不太感兴趣了,因此要努力创设幼儿感兴趣的阅读区,让幼儿在区域中快乐的阅读,并加强对幼儿在区域中阅读的指导策略,发挥阅读区的教育价值。  相似文献   

15.
为了探索悲伤刺激下的关键情感神经回路,利用功能核磁共振信号进行了动态因果建模.在Papez环路和相关先验知识的基础上建立情感环路的固有连接模型,并相应建立了3个调节连接模型.在这些模型中,实验刺激作用于不同的连接点,它们对脑区间的神经活动影响及对神经活动的调节方式都各自不同.然后通过贝叶斯模型比较,选出了最优模型.从群组分析中发现抑郁症患者前扣带回至右额下回的固有连接和调节连接均显著强于健康被试.随后将这些功能连接参数作为特征用于抑郁症分类,其中SVM分类器的准确率为80.73%.这也在一定程度上验证了功能连接用于抑郁症识别的有效性,并为抑郁症临床诊断提供了新的思路.  相似文献   

16.
Objective: To study the regulation of blood pulse volume via photoplethysmography (PPG) signal detected from toe, while the lower limb is passively raised in different height positions. Methods: Use a modified non-invasive PPG technique to detect the blood pulse signal on toe with infrared (IR) photo sensor. A protocol consisting of two postures, i.e., supine and 45° reclining, was designed to conduct laboratory trial in this study. During the period of performing the protocol of these postures, the lower limb was passively raised from the heights of 10 cm to 60 cm randomly and individually with sponge blocks underneath the foot. Results: In the supine posture, the higher the foot was passively raised, the more the blood PPG signal decreased. In the 45° reclining posture, the blood PPG signal increased at the beginning and then decreased in the foot height position from 10 cm to 60 cm. In both postures the normalized AC signal changes significantly while the normalized DC signal changes little. Conclusion: The toe PPG signals can obviously indicate the regulated blood volume change with the designated postural procedures due to the heart level position.  相似文献   

17.
介绍一种基于动态关联和卡尔曼滤波的脉冲串去交错方法,该方法将电子侦察系统截获的参数脉冲幅度(PA)与脉冲到达时间(TOA)结合起来作为去交错的依据。仿真结果表明,在载频与脉宽等参数相近的情况下,该方法能很容易的实现脉冲去交错。  相似文献   

18.
基于随机共振理论的低速重载齿轮故障诊断研究   总被引:2,自引:0,他引:2  
基于随机共振理论,结合包络解调分析研究微弱低频幅值调制信号的增强与提取,并应用于低速重载齿轮的故障诊断.先将低频幅值调制信号输入到双稳非线性系统,运用信号自含噪声或外加噪声,实现随机共振现象,然后再进行包络解调分析.对模拟调幅信号和实测低速重载齿轮箱振动信号的分析结果,证实所提出方法的有效性和优越性.  相似文献   

19.
基于无线传感器网络的车流量检测系统,通过磁阻传感器检测车流量信号,利用ZigBee无线传感器网络发送检测信息到汇聚节点,以供智能交通系统使用。实验表明,由该检测节点组成的车流量检测系统能够准确检测车流量信息。  相似文献   

20.
脉冲场凝胶电泳是分离大分子DNA片段的有效方法.就脉冲场凝胶实验中遇到的问题及解决方法进行了探讨,在充分理解实验原理的基础上对脉冲场凝胶电泳的实验条件进行优化,最终达到利用脉冲场凝胶电泳得到大分子DNA片段清晰整齐电泳条带的实验效果,为后续实验奠定了基础.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号