Physiological Signal Analysis and Applications in Cardiology

• Main Authors: I-Chi Chou, 周以琪
• Other Authors: Ren-Guey Lee
• Format: Others
• Language: en_US
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/4zpxmm

博士 === 國立臺北科技大學 === 電腦與通訊研究所 === 97 === The primary goal of this dissertation is to propose an effective ECG signal compression algorithm and the safety strategy in a novel Holter. As the growth of health-care applications the most remarkable trend in the transmission field, more and more data need to be transmit to the remote care center for various services. Generally, the Holter monitor is usually utilized to record user’s ECG signal with long-tern monitoring which caused a huge amount of data to be processed and transmitted; however, the transmission bandwidth is limited. In addition, the novel Holter is designed of battery powered and CPU with limited computation ability for portable. Hence, the requirement of Holter is to apply an effective and simple algorithm for reducing the data amount under the limitation of computation ability and communication bandwidth. In this dissertation, the portable Holter is utilized to identify the ECG signal by the proposed arrhythmia recognition algorithm and send the abnormal beat to the home gateway via wireless technology. Due to the bandwidth limitation of communication technology, the home gateway can compress the received data from Holter and transmit to the remote care center through wired/wireless transmission medium. The adopted compression algorithm not only helps to control the reconstruct error according to the relationship of energy but also reduces computation efforts without inverse wavelet transform. From a different viewpoint, the information security problem is a major issue for data transmission, thus, this study also researched the topic in data delivery of Holter. In order to transmit user’s information through communication channel, the Tame Transformation Signature (TTS) technology is applied to encrypt private data. TTS is one of the multivariate public key cryptosystems which has the prominent advantages of fast key generation and low computation to fit the conditions of Holter. The other safety issue is in relation to Holter device while user using it. Holter is consisted with numerous electronic components and operated by user; nevertheless, there are some potential hazards need to be controlled. For this reason, the Failure Mode and Effects Analysis (FMEA) method is utilized to assess the risk of Holter. By systematic analysis, this study can identify the potential risks and provide applicable protection system for improving safety in Holter. As above mentioned, the compression algorithm with symptom recognition and the safety strategies are used in the Holter and tested the performance and accuracy according to the MIT-BIH database. In the experiment result, the average accuracy of arrhythmia recognition is 98.38% for MIT-BIH database, and the compression rate is flexible with a controllable percent root-mean-square difference (PRD). TTS technology provides high speed and low calculations, in which the average time to write a signature is 0.0187ms. In addition, the average time to generate private key and public key is 0.0515ms and 0.0547ms respectively. Finally, the FMEA analysis is utilized to discover the potential risks from component or user’s operation. According to the analytic results, two protection system are provides to decrease the risks of Holter.