基于iOS平台的脉搏血氧仪设计与实现

血氧饱和度的监测对生理健康具有极为重要的意义,为了实现对人体血氧饱和度的无线测量和远程分享,提出了一种基于iOS操作系统的脉搏血氧饱和度测量系统。该系统利用集成了低功耗蓝牙协议栈的单片机CC2540对光电容积脉搏波信号进行采集,使用蓝牙传输协议把数据实时的上传到iOS操作系统,利用iOS操作系统对信号进行数字信号处理,根据修正的朗伯-比尔定律计算出血氧饱和度和脉率,最终把测量结果上传到云端服务器。实验结果表明,该系统可以实现血氧饱和度的无创实时监测、脉搏波数据的存储、测量结果上传云端服务器和分享测量结果的功能。     

一种改进可穿戴设备的血氧测量精度的传感器设计与验证

改进智能穿戴设备上传感器的数据采集方法,以及血氧测量和数据处理的方法,找到在动态测量过程中血氧数据更加精确的测量计算方法.修正现有算法分析模型,提取典型测量数据,设计新的变量标值,分析比较动态变化后的数据相关性,建立原始数据和输出动态血氧数据之间的关系变化模型,通过多人动态变化场景的数据采集实验验证了该方法的有效和精确.结果表明结合硬件设计、反射波长选择,通过血氧饱和度数值的动态变化反应血液中供氧情况,提出一个新的转换关系算法模型,得到精确度达到99％的血氧数据是非常实用和有效可行的方法.改进传统的投射式脉搏波血氧饱和度检测的算法模型到反射式脉搏波血氧饱和度的检测方式,提升其在智能穿戴设备上监测的血氧动态监测精度,该方法得到的数据对判定人体的健康状态和疾病类型非常有帮助.     

连续测量血氧饱和度的视觉方法

血氧饱和度是人体的重要生命体征指标.文章通过深入分析基于动脉血液容积脉搏波的生理活动机理,及基于容积脉搏波的血氧饱和度测量原理和方法,提出了一种基于视频的无创连续测量血氧饱和度的新方法.该方法通过混合光照射动脉血液,并采用摄像头捕获血流视频,最终根据血流容积和血液颜色的连续变化来逐拍计算出血氧饱和度.结果显示,与专业设备所测数据相比,该方法测量结果准确性高、稳定可靠.     

基于安卓手机的血氧与脉搏测量系统的设计

为了能实现对运动员的血氧饱和度和脉搏的快速测量并远程发送给教练和医生,设计了一种远程血氧饱和度与脉搏测量系统。检测模块检测血氧脉搏信号,通过蓝牙发送给运动员手机,手机端软件对信号数据进行处理计算并显示血氧饱和度、脉搏和脉搏波形。运动员手机端的软件同时通过网络将上述信号数据发送给远端服务器,经过服务器转发给教练与医生的手机。经测试,测量数据精度较高,系统工作稳定。     

脉搏血氧饱和度远程实时监护系统设计

为实现医生同时对多个患者的血氧饱和度的远程实时监护,设计了一种基于因特网的脉搏血氧远程实时监护系统.该系统分为患者端和医生端.患者端采用以C8051F320为处理核心的血氧检测电路提取相关血氧信号,通过USB传输到上位机进行处理、分析和显示;并通过因特网将数据实时发送至远程医生端显示、存储.实验测试表明,该系统具有延时小、可靠性较高和较大的应用前景等优点.     

基于交直流分离的反射式血氧饱和度测量系统的设计

肝储备功能是评价肝脏正常生理活动的重要依据,动脉血氧饱和度是肝储备功能测量的重要中间变量,针对长时间连续无创血氧饱和度测量的要求,提出基于交直流分离的反射式血氧测量系统的设计方案。通过测量手指、耳尖等皮肤薄弱部位的反射式光电容积脉搏波,利用交直流信号分离处理技术,基于动脉血氧饱和度经验测量公式,实现长时间无创动脉血氧饱和度测量。交直流分离技术的使用能够有效的降低系统干扰和噪声的影响,优化血氧饱和度测量结果;经临床医疗对比实验检测,证明系统误差符合实际测量要求。     

基于FPGA的脉搏血氧饱和度检测系统设计

血氧饱和度是衡量人体血液携带氧能力的重要参数,也是临床诊断和家庭保健中重要的生理指标。根据红外光谱法血氧饱和度测量原理,设计了一种血氧饱和度测量系统。系统以FPGA为开发平台,包括RSJ048CAS指夹式脉搏血氧探头、AD采集模块、信号调理模块、控制显示模块等模块,它可以实时、连续和无创地进行血氧饱和度检测。实验结果表明,在安静状态下,该系统可实现测得的血氧饱和度不低于94%。     

一种单片便携式脉搏血氧饱和度测量仪的研制

根据红外光谱法血氧饱和度测量原理,以MSP430为开发平台,设计了一种便携式无线脉搏血氧仪.设计中采用了一种新型的腕式血氧探头,使用户佩戴和测量更加方便;硬件设计上充分利用了单片机内部的功能模块,使外围元件个数减到最少,功耗降到最低;软件设计上实现了信号调制、信号处理、信息显示和无线通信等功能.实验样机的初步测量结果表...     

基于GPRS的多参数移动监护仪的设计与实现

采用GPRS技术,W78E58B微处理器作为控制核心,研制一种便携式多参数移动监护仪,可以实时测量心电、心率、血压、体温以及血氧饱和度,具有数据分析、异常报警功能,并可通过GPRS将数据传输到监护中心。     

集成多生理参数监测的终端设计

针对目前健康监测终端设备的弊端,设计了一种便携式多生理参数监测终端.终端设备以ARM微处理器STM32 F405为控制与信号处理核心,通过对多种传感器采集的信号进行实时处理和分析,获取脉率、呼吸、血氧饱和度(SPO2)、脉搏传输时间(PTT)、心电图(ECG)以及光电容积脉搏波(PPG)信息,可实时显示生理参数和波形信息,通过触控屏完成人机交互功能,可方便实现手持式和穿戴式测量方式的自由切换.测量数据可本地存储或者通过蓝牙、Zig Bee无线发送.通过实验测试,该设备测量的生理参数数据准确可靠.     

Developing a monitoring psychological stress index system via photoplethysmography

The purpose of this work was to assess the psychological stress index (PSI) by using oxyhemoglobin saturation by SpO₂ [i.e., the plethysmograph (PPG) signal], which can be measured easily and conveniently. We use the plethysmograph amplitude (PPGA) and the heart-beat interval (HBI) extracted from the SpO₂ waveform to obtain the stress index and to quantify it from 0 to 100. The respiration rate can also be extracted from the heart-rate interval, as shown in our previous research. Therefore, the PPG signal can display the heart rate, SpO₂ waveform, SpO₂ concentration, respiration rate, and psychological stress index. This methodology was tested on nine volunteer Taiwanese students under the stress of an English presentation. The experiment, which takes 30 min for each student, was separated into three stages: preparation, presentation, and discussion, and relaxation. The PSI values of these three stages were 49 ± 10, 60 ± 11, and 56 ± 10, respectively. The results were very successful, and showed PSI values changing from low, to high, and back to low during these three stages. In the near future, we hope to implement this system into a robotic wheelchair in order to monitor the PSI of elderly patients in a nursing home, and to evaluate their psychological condition based on this method.     

锂-亚硫酰氯电池储存寿命研究

锂-亚硫酰氯电池作为一种免维护、高比能、长储存寿命电池,目前已经在以国防领域为代表的国民经济中得到了广泛应用;其储存寿命的考核在行业内尚属难题;通过广泛、深入地调研和对前期锂-亚硫酰氯电池储存数据的收集整理,研究了锂-亚硫酰氯电池的储存寿命影响因素及其试验评估方法;通过研究得知,锂-亚硫酰氯电池的储存寿命试验应尽早备样,若时间紧迫可通过加速试验方法;提出了通过等效储存试验时间来评估电池储存寿命及其可靠度的方法,指出当等效储存试验时间不足时,应安排样本进行容量回归分析,得出其退化规律;此外,还要对电池储存末期热性能进行分析;在以上工作基础上对电池储存寿命进行综合评估;最后,通过案例分析,进行了工程演算;为后续锂-亚硫酰氯电池储存寿命评估提供了参考。     

基于DTW的贝叶斯方法在睡眠和唤醒分类中的应用

许多方便的可穿戴设备被用于医疗用途,如测量心率（HR）、血压和其他信号. 随着睡眠质量监测问题的出现,如何从这些信号中区分睡眠和唤醒状态成为关键问题. 提出了一种基于动态时间规整（DTW）的贝叶斯方法用于睡眠和唤醒分类. 利用心率和血氧饱和度（SpO2）的信号去分析睡眠状态和一些睡眠相关问题. 利用DTW从原始的心率、血氧饱和度信号中提取特征,然后贝叶斯分类方法用于区别睡眠和唤醒状态. 最后,从睡眠心脏健康研究网站收集数据的一个真实案例研究验证了基于DTW的贝叶斯方法的可行性和优势.     

Development of a linear predictive model for carbon dioxide sequestration in deep saline carbonate aquifers

CO₂ injection into deep saline aquifers is a preferred method for mitigating CO₂ emission. Although deep saline aquifers are found in many sedimentary basins and provide very large storage capacities, several numerical simulations are needed before injection to determine the storage capacity of an aquifer. Since numerical simulations are expensive and time-consuming, using a predictive model enables quick estimation of CO₂ storage capacity of a deep saline aquifer. In order to create a predictive model, the ranges of variables that affect the CO₂ storage capacity were determined from published literature data. Correlations found in literature were used for other important parameters such as pore volume compressibility and density of brine. Latin hypercube space filling design was used to construct 100 simulation cases prepared using CMG STARS. The simulation period covered a total of 300 years of CO₂ storage. By using a least-squares method, linear and nonlinear predictive models were developed to estimate CO₂ storage capacity of deep saline carbonate aquifers. Numerical dispersion effects were considered by decreasing the grid dimensions. It was observed that a dimensionless linear predictive model is better than the nonlinear. The sensitivity analyses showed that the most important parameter that affects CO₂ storage capacity is depth. Most of the (up to 90%) injected gas dissolved into the formation water and a negligible amount of CO₂ reacted with carbonate.     

半张量积压缩感知模型的l0-范数解

目的 半张量积压缩感知模型是一种可以有效降低压缩感知过程中随机观测矩阵所占存储空间的新方法,利用该模型可以成倍降低观测矩阵所需的存储空间。为寻求基于该模型新的重构方法,同时提升降维后观测矩阵的重构性能,提出一种采用光滑高斯函数拟合l₀-范数方法进行重构。方法 构建降维随机观测矩阵,对原始信号进行采样;构建可微且期望值为零的光滑高斯函数来拟合不连续的l₀-范数,采用最速下降法进行重构,最终得到稀疏信号的估计值。结果 实验分别采用1维稀疏信号和2维图像信号进行测试,并从重构概率、收敛速度、重构信号的峰值信噪比等角度进行了测试和比较。验证结果表明,本文所述算法的重构概率、收敛速度较该模型的l_q-范数（0 <q <1）方法有一定的提升,且当观测矩阵大小降低为通常的1/64,甚至1/256时,仍能保持较高的重构性能。结论 本文所述的重构算法,能在更大程度上降低观测矩阵的大小,同时基本保持重构的精度。     

Experimental determination of the liquidus in the high basicity region in the Al2O3(30 mass%) - CaO - MgO - SiO2 system

The liquidus in the high basicity region in the Al₂O₃(30 mass%)-CaO-MgO-SiO₂ system were determined experimentally at 1773 and 1873 K using the quench technique followed by EPMA analysis. Based on the experimental data, a phase diagram of the Al₂O₃(30 mass%)-CaO-MgO-SiO₂(<20 mass%) section was constructed for 1773 and 1873 K. The solubilities of 2CaO.SiO₂ and 3CaO.SiO₂ at 1773 K were found to be considerably higher in comparison with the existing phase diagram. Even the solubility of MgO at 1873 K was found to be somewhat higher. In addition, the activities of MgO, CaO and Al₂O₃ at 1773 K were estimated using the phase diagram information.     

输出饱和线性系统的稳定性及L2增益性能

考虑输出饱和线性系统的稳定性以及L     

Anti-windup compensation for systems with sensor saturation: a study of architecture and structure

This article proposes a linear dynamic anti-windup strategy for the alleviation of performance and stability problems in systems which are linear apart from saturating sensors. Unlike anti-windup compensation for systems subject to actuator saturation, there is no agreed architecture for applying anti-windup to systems with sensor saturation and therefore attention is devoted to the discussion of various candidate configurations which can be interpreted as a particular choice of a static non-linear map. The main results of the article give existence conditions for compensators which yield global exponential stability and finite ?₂ gain of the overall non-linear closed-loop system. The existence conditions are different to those which have appeared hitherto in the literature.     

Mixed H2/H∞ distributed robust model predictive control for polytopic uncertain systems subject to actuator saturation and missing measurements

In this paper, we discuss the mixed H₂/H_∞ distributed robust model predictive control problem for polytopic uncertain systems subject to randomly occurring actuator saturation and packet loss. The global system is decomposed into several subsystems, and all the subsystems are connected by a fixed topology network, which is the definition for the packet loss among the subsystems. To better use the successfully transmitted information via Internet, both the phenomena of actuator saturation and packet loss resulting from the limitation of the communication bandwidth are taken into consideration. A novel distributed controller model is established to account for the actuator saturation and packet loss in a unified representation by using two sets of Bernoulli distributed white sequences with known conditional probabilities. With the nonlinear feedback control law represented by the convex hull of a group of linear feedback laws, the distributed controllers for subsystems are obtained by solving an linear matrix inequality (LMI) optimisation problem. Finally, numerical studies demonstrate the effectiveness of the proposed techniques.