基于改进EEMD的心电信号基线漂移消除方法

针对传统方法滤波效果不佳的问题,本文提出了基于改进集合经验模态分解（Ensemble empirical mode decomposition,EEMD）的消除心电信号基线漂移方法。该方法克服了经验模态分解（Empirical mode decomposition,EMD）模态混叠的问题,并对EEMD方法存在的问题和不足进行改进,建立集合经验模态分解方法中加入辅助白噪声大小的可依据准则,从而确定加入的辅助白噪声大小以及集合平均次数这两个重要参数。它从含噪心电信号中提取基线漂移信号,然后重构其余本征模函数（Intrinsic mode function,IMF）分量得到\"干净\"的心电信号,为后续的研究提供前提。经实验验证表明：相较于传统方法,这种方法能够提高信噪比、降低均方差、保持特征波形、去噪更加彻底,很好地解决了心电信号低频成分损失的问题。     

基于心动周期和经验模式分解的心电信号去噪处理

针对现有心电信号（Electrocardiogram,ECG）去噪方法难以精准剥离与之频带重叠的肌电干扰并无损提取到“干净”ECG的问题,提出了利用心动周期和经验模式分解对含噪ECG进行去噪处理。本文方法首先对含噪ECG进行经验模式分解,然后利用心动周期判断固有模态函数分量属于噪声还是有用信号,最后将有用信号的固有模态函数分量重构ECG。为验证本文去噪方法,首先采用ECG动力学仿真模型评估本文方法在不同参数噪声下的去噪效果;其次选取MIT-BIH数据库中的基线漂移信号bw,肌电干扰信号ma和105号、107号、123号ECG分别构建3组真实含噪ECG进行实验。评估与实验结果均表明本文方法可以简单、有效地同时去除ECG中的肌电干扰和基线漂移,去噪效果优于普通经验法。     

Telescreens, keypens, and the expert: A 60 year snapshot

Brian Shackel was responsible for initiating the first international conference on human–computer interaction, INTERACT ’84. This was in the same year to which George Orwell referred in the now-classic book, Nineteen Eighty-Four. Both texts share the common theme of being concerned with information and its effects on the individual. In Professor Shackel’s paper (the focus here), both aspects are considered over a 60-year lifespan – with a particular emphasis on his interest on “Designing for People in the Age of Information”. This keynote address at the INTERACT conference is reviewed and the accuracy of his many predictions for the future considered. It is concluded that despite Professor Shackel’s preoccupation with designing for humans some quarter of a century ago, there still is much work to do.     

基于经验模态分析心电信号预处理研究

心电信号是典型的强噪声下非平稳弱信号,其分析效果受各种干扰影响很大。因此,选择有效的滤波方法对心电信号分析有着非常重要的意义。提出一种基于经验模态分解阈值处理的新滤波方法用于心电信号预处理,并以MIT/BIH标准数据库中的心律失常数据作为仿真对象进行仿真分析,并取得了令人满意的消噪效果。     

A Safe-Control Paradigm for Human–Robot Interaction

This paper introduces a new approach to control a robot manipulator in a way that is safe for humans in the robot's workspace. Conceptually the robot is viewed as a tool with limited autonomy. The limited perception capabilities of automatic systems prohibits the construction of failsafe robots of the capability of people Instead, the goal of our control paradigm is to make the interaction with a robot manipulator safe by making the robot's actions predictable and understandable to the human operator. At the same time the forces the robot applies with any part of its body to its environment have to be controllable and limited. Experimental results are presented of a human-friendly robot controller that is under development for a Barrett Whole Arm Manipulator robot.     

基于经验模式分解的汉字字体识别方法

提出了一种基于经验模式分解(empirical mode decomposition,简称EMD)的汉字字体识别方法.通过对大量汉字字体的研究比较,选取了能反映汉字字体基本特征的8种基本笔画.以这8种汉字笔画为模板,在汉字文档图像块中随机地抽取笔画信息,形成笔画特征序列.通过对笔画特征序列作EMD分解,提取每个笔画特征序列的高频能量,并结合汉字文档图像块的平均灰度,形成字体识别的一个9维特征.     

EEMD方法在刀具磨损状态识别的应用

总体经验模态分解(EEMD)方法在EMD的基础上消除了模态混叠的现象,从而更能准确地揭露出信号特征信息。根据声发射信号的非稳态、非线性的特点,提出一种基于EEMD应用于刀具磨损状态识别的方法。通过EEMD获取无模态混叠的IMF分量;通过敏感度评估算法从所有IMF分量中提取敏感的IMF;提取敏感IMF的能量作为支持向量机(SVM)分类器的输入,将刀具分成正常切削、中期磨损和严重磨损3种状态。通过比较EEMD与应用EMD等方法的分类准确率,确立了基于EEMD的方法在提取刀具磨损状态特征信息的优势。     

Recognizing body poses using multilinear analysis and semi-supervised learning

This paper presents an approach to full-body human pose recognition using features extracted from stereo silhouettes via multilinear analysis in a semi-supervised learning framework. Inputs to the proposed approach are pairs of silhouette images obtained from wide baseline binocular cameras. Through multilinear analysis, low dimensional view-invariant pose coefficient vectors can be extracted from these stereo silhouette pairs. Taking these pose coefficient vectors as features, a recently proposed state-of-the-art semi-supervised learning method, Universum, is adopted for pose recognition. Experiment results obtained using real image data showed the efficacy of the proposed approach.     

Critic Systems – Towards Human–Computer Collaborative Problem Solving

Human–computer collaboration is extremely necessary for solving ill-structured problems and critic systems can effectively facilitate human–computer collaborative problem solving. This paper conducts a systematic study on critic systems. First, the concepts of critic systems are presented. Then, a literature review is presented on critic systems. Afterwards, a generic architecture is put forward for critic systems, with its important aspects being analyzed. Finally, two case studies are given to illustrate critic systems.     

Automated Support for Building and Extending Expert Models

Building a knowledge-based system is like developing a scientific theory. Although a knowledge base does not constitute a theory of some natural phenomenon, it does represent a theory of how a class of professionals approaches an application task. As when scientists develop a natural theory, builders of expert systems first must formulate a model of the behavior that they wish to understand and then must corroborate and extend that model with the aid of specific examples. Thus there are two interrelated phases of knowledge-base construction: (1) model building and (2) model extension. Computer-based tools can assist developers with both phases of the knowledge-acquisition process. Workers in the area of knowledge acquisition have developed computer-based tools that emphasize either the building of new models or the extension of existing models. The PROTÉGÉ knowledge-acquisition system addresses these two activities individually and facilitates the construction of expert systems when the same general model can be applied to a variety of application tasks.     

Automated Knowledge Acquisition for Strategic Knowledge

Strategic knowledge is used by an agent to decide what action to perform next, where actions have consequences external to the agent. This article presents a computer-mediated method for acquiring strategic knowledge. The general knowledge acquisition problem and the special difficulties of acquiring strategic knowledge are analyzed in terms of representation mismatch: the difference between the form in which knowledge is available from the world and the form required for knowledge systems. ASK is an interactive knowledge acquisition tool that elicits strategic knowledge from people in the form of justifications for action choices and generates strategy rules that operationalize and generalize the expert's advice. The basic approach is demonstrated with a human–computer dialog in which ASK acquires strategic knowledge for medical diagnosis and treatment. The rationale for and consequences of specific design decisions in ASK are analyzed, and the scope of applicability and limitations of the approach are assessed. The paper concludes by discussing the contribution of knowledge representation to automated knowledge acquisition.     

Using intentional models for the interface design of multi-level systems

In this paper, it is argued that the design of computer interfaces for complex, multi-layered systems needs to take into account the differing intentional models that are held by different types of users of such systems, and that there is a strong correlation between the job roles of individuals and the level of abstraction of the mental models held by such users. An approach to the analysis and design of complex multi-layered systems based on the analysis of job roles to elicit such models is suggested and linked with other techniques of task analysis and object-oriented analysis and design. The methodology is illustrated with the interface analysis for an automatic environmental chemical analyser.     

运动传感器辅助的心电运动伪迹识别与消除方法

运动伪迹是动态心电监护的主要干扰,严重影响临床诊断的误诊率和漏诊率.为了改善动态心电信号质量,设计了一种运动传感器辅助的动态心电监护设备,采集V2导联心电信号,通过腹部运动传感器数据识别易引起心电运动伪迹的日常活动,标记运动伪迹位置,引入PQRST波特征点检测、自适应滤波算法消除运动伪迹.实际佩戴测试结果表明:此法可有效识别咳嗽、蹲、坐等日常运动,并有效消除此类运动产生的心电运动伪迹.     

一种基于EMD的人脸图像光照问题处理方法

鉴于经验模态分解（EMD）算法的无参数特性和基于数据驱动的自适应分析,从EMD算法筛选过程中插值点和差值算法选取的角度出发,提出了一种标准EMD的改进算法。用改进的EMD算法分解需要识别的人脸图像,得到从整体上有效消除了光照变化影响的原人脸图像的重构图像,并将重构图像用于识别。通过在Yale B人脸库上的实验结果表明,将提出的光照处理方法应用到人脸识别中可以取得较好的效果。