基于眼电信号的人机交互系统研究进展

人机交互（HCI）是借助电子计算机技术而发展起来的一门技术科学，同时也是人类与计算机之间相互交流与通信 的一种方法。眼电信号（EOG）是一种通过电极记录下来、由眼球视网膜与角膜之间电势差形成的生物电信号，在服务于 肢体运动控制障碍患者方面，由EOG控制的无障碍HCI系统发挥着越来越重要的作用。本研究归纳了EOG控制的HCI 系统的建立和发展历程，对眼球运动进行探测的常用方法:搜索线圈法、红外线眼动图法、Purkinje影像追踪法、基于计算 机图形学的方法和EOG进行了介绍，总结了EOG控制的HCI系统在残障人医疗辅助以及危险环境下进行作业方面的应 用，最后分析了由EOG控制的HCI系统存在的局限性及其未来的发展趋势。     

生物电信号实时分析系统

本文介绍一种生物电信号实时分析系统。在该系统中通过与生物实验仪器相连接的A/D转换器,采集生物电信号并把它们输入计算机进行存储,同时对动作电位潜伏期及其电位峰值,兴奋性突触后电位的潜伏期及其电位峰值进行分析。然后以数字形式和图形曲线形式通过屏幕和X-Y绘图仪在几分钟内输出。采样的速率从30微秒起,用户可以根据需要进行调整,以最快速度计算每秒钟可采集三万个数据,相对精确度达万分之二点五。读系统使用方便,不需要计算机方面的专业知识,适于生物或医学工作者使用。     

眼动系统研究

Ⅳ主动性眼动系统引言眼动的类型有多种,除前述的前庭眼动系统(一般为眼震形式)外,还有一大类是是受意识控制的眼动(或称主动眼动过程)。按刺激形式可分为以下几类: ·凝视系统·扫视系统·视跟踪系统·视动系统·幅辏系统本文主要对两个较为简单的眼动系统——扫视系统和视跟踪系统作些介绍,其他系统只作简要叙述。     

神经电信号中眼轮匝肌功能状态的识别

目的:提取能反映眼轮匝肌功能活动的狗面神经颧支的神经电信号(ENG),通过对ENG信号的分析,识别出眼轮匝肌的功能状态。方法:利用植入到狗面神经颧支周围的Cuff电极提取有闭眼动作发生期间的神经电信号,采用幅度阈值法,通过对ENG信号的分析,识别出闭眼动作发生时眼轮匝肌的收缩动作。结果:研究中我们提取到了能反映闭眼动作发生的ENG信号,并且通过对信号的分析,识别出了眼轮匝肌收缩动作的发生。结论:可以通过对眼轮匝肌支配神经上ENG信号的分析,监控眼轮匝肌的功能状态。     

扫视眼动的系统分析方法—建模

眼动系统在神经系统研究及临床应用上都具有重要作用。从研究方法上讲，可概括为系统分析方法及信号处理方法。采用系统分析方法进行研究的一个很重要的工作就是建立系统的数学模型，特别是与生理解剖相一致的同胚模。本文即对扫视眼动系统同胚模型的建立进行了综述。     

8098单片机脑电自动分析系统

单片微机以其价格低廉、体积小、可靠性高等突出优点日益受到人们的重视，应用十分广泛。目前国内普遍采用的是八位单片机，如ＭＣＳ４８系列、ＭＣＳ－５１系列等。本文介绍了一种用ＭＣＳ－９６系列的准１６位单片机８０９８组成的脑电自动分析系统，它能将对称导联的δ、θ、α和β节律的频率和幅度之分布情况以直方图和数字两种形式由打印机输出，便于医生分析比较，这不仅提高了分析脑电图的效率，而且提高了分析的可靠性。该系统体积小、成本低，便于推广。文章介绍了该系统的硬件和软件的基本原理，对设计技巧进行了分析和讨论。     

一种用小波包变换提取眼电信号警觉度特征的方法

警觉度是指人集中注意力执行某项任务时所表现出的灵敏程度。为保证生产安全,很多岗位需要对工作人员的警觉度进行估计和预测,如高铁司机和危险品运输司机等。基于脑电和眼电等生理信号的警觉度估计与预测是警觉度研究的一个重要方向,如何提取眼电信号中的警觉度特征是该研究的核心问题之一。本研究应用小波包变换方法从水平眼电中提取不同频段能量的比值,以期找出高相关度的警觉度特征。探讨了水平眼电中16种不同的低高频分段的能量比特征,对特征分别进行了移动平均和线性动力系统去噪处理。实验表明,分段为(0～1.50 Hz)/(1.50～31.25 Hz)的能量比值与警觉度的相关系数最高。35组实验的相关系数平均值为0.742,标准差为0.151,比已有的慢速眼动、快速眼动以及眨眼等11种特征中最好特征的相关系数平均值提高了5.55%,标准差降低了6.62%。     

小波变换及脑电信号综合分析系统的研究

本文介绍了小波变换、脑电信号的特点和分析方法，以及脑电信号综合分析系统的硬件结构，并阐述了系统软件的设计和实现方法。该系统的软件具有良好的兼容性、可靠性和实时性，功能齐全，可用于脑电信号的分析、监护和反馈研究。     

基于微机的心电信号实时自动分析系统

作者介绍了在３８６微机上研制开发的心电信号实时自动分析系统，着重介绍了ＱＲＳ复合波的帝时检测算法和心律失常自动分析软件。该系统能实时显示任一导联心电波形，同时显示心率（ＨＲ）和早搏（ＰＶＣ）累积数；能自动识别十余种心律失常并报警；具有ＳＴ段分析功能，能实时检测ＳＴ段电平和斜率，经用美国ＭＩＴ心电数据库的部分数据对该系统进行测试，准确率达９５％以上。     

经变异非线性动力学分析的状态空间重构方法

本文讨论了在使用研究非线性动力学方法研究心率变异时的状态空间重构问题。通过对这一方法的理论基础的讨论，说明在非线性建模中直接使用ＲＲ间期不合理性。本文以嵌入学为基础提出了一个合理的建模方法，对临床数据进行了分析，并给出了对比分析结果。     

A Single-Channel System for Recording Eye Movements

A single-channel method of recording eye movements, using two active electrodes, is described. Illustrations are presented of its accuracy, efficiency, and degree of common-mode rejection. The method appears to offer advantages in possible computer scoring of eye-movement data, as well as improvements in speed and accuracy of hand-scoring such data.     

三通道动态心电记录分析系统

作者介绍中心研制的一种三通道Ｈｏｌｔｅｒ系统，用于和时间动态心电图的记录和分析。此系统在硬件线路中采用了专门的校正技术，以补偿记录器因带速不稳带来的误差，该系统的记录器功耗十分低，可以连接记录７２小时的动态心电图，系统软件内容丰富，功能完善，整个系统性能稳定可靠，具有较高的性能价格比。     

A System for Recording High Fidelity Cough Sound and Airflow Characteristics

Cough is considered an early sign of many respiratory diseases. Recently, there has been increased interest in measuring, analyzing, and characterizing the acoustical properties of a cough. In most cases the main focus of those studies was to distinguish between involuntary coughs and ambient sounds over a specified time period. The objective of this study was to develop a system to measure high fidelity voluntary cough sounds to detect lung diseases. To further augment the analysis capability of the system, a non-invasive flow measurement was also incorporated into the design. One of the main design considerations was to increase the fidelity of the recorded sound characteristics by increasing the signal to noise ratio of cough sounds and to minimize acoustical reflections from the environment. To accomplish this goal, a system was designed with a mouthpiece connected to a cylindrical tube. A microphone was attached near the mouthpiece so that its diaphragm was tangent to the inner surface of the cylinder. A pneumotach at the end of the tube measured the airflow generated by the cough. The system was terminated with an exponential horn to minimize sound reflections. Custom software was developed to read, process, display, record, and analyze cough sound and airflow characteristics. The system was optimized by comparing acoustical reflections and total signal to background noise ratios across different designs. Cough measurements were also collected from volunteer subjects to assess the viability of the system. Results indicate that analysis of cough characteristics has the potential to detect lung disease.     

Tracking-Cuff System for Beat-to-Beat Recording of Blood Pressure

A system is described for the automatic beat-to-beat tracking of blood pressure (BP) based on the detection of Korotkoff sounds. Upon each detection, a discrete adjustment in cuff pressure is made prior to the next cardiac cycle. In comparison with other continuous tracking systems, digital control allows for estimation of systolic BP based on precise knowledge of cuff pressure at each heart beat. Simultaneous recordings of intra-arterial pressure (radial artery) and systolic pressure measured with the tracking system were made in 4 subjects during 1-min trials of resting, paced respiration, and mental arithmetic. Correlations of the paired measures of intra-arterial and cuff pressure for 27 trials varied from .46 to .90 (median = .72). The standard error of estimate of intra-arterial systolic BP varied from 1.8 to 6.3 mmHg (median = 3.6). The system can be used without discomfort to track systolic BP for 60 and 120 sec in experiments involving repeated cuff inflations. Critical features and advantages of the tracking-cuff system for blood pressure measurement and biofeedback are discussed.     

基于LabVIEW的多通道脉搏波记录处理系统

本文描述了一个基于LabVIEW的虑拟仪器系统。该系统能采集、记录和处理人体多处典型部位的脉搏波，用改进的高斯函数（钟形波）叠加模型，通过北线性拟合算法----Levenberg-Marquardt（LM）算法提取脉图特征。实验表明：该模型和算法能简单有效地对各类脉图进行特征识别，识别率达到90％以上。     

A Transducer for the Clinical Recording of Ocular Microtremor

In summary, let me say that the transfer of technology can be managed successfully. In the context of 3i as a whole, we have supported 1600 start-ups in the last five years although, obviously, not necessarily in high-tech industries. In 1987 3i Ventures fully expects to invest a further few million pounds in either start-ups or pre-stock market companies within the health-care and biotechnology sectors. It requires that everyone involved, including the venture capitalist, fulfils their rôle with commitment. It can be a difficult and lengthy process, but it can also be fun and very rewarding.