• Korean Circulation Journal
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• 제54권3호
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• pp.140-153
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• 2024

Background and Objectives: Although a single-lead electrocardiogram (ECG) patch may provide advantages for detecting arrhythmias in outpatient settings owing to user convenience, its comparative effectiveness for real-time telemonitoring in inpatient settings remains unclear. We aimed to compare a novel telemonitoring system using a single-lead ECG patch with a conventional telemonitoring system in an inpatient setting. Methods: This was a single-center, prospective cohort study. Patients admitted to the cardiology unit for arrhythmia treatment who required a wireless ECG telemonitoring system were enrolled. A single-lead ECG patch and conventional telemetry were applied simultaneously in hospitalized patients for over 24 hours for real-time telemonitoring. The basic ECG parameters, arrhythmia episodes, and signal loss or noise were compared between the 2 systems. Results: Eighty participants (mean age 62±10 years, 76.3% male) were enrolled. The three most common indications for ECG telemonitoring were atrial fibrillation (66.3%), sick sinus syndrome (12.5%), and atrioventricular block (10.0%). The intra-class correlation coefficients for detecting the number of total beats, atrial and ventricular premature complexes, maximal, average, and minimal heart rates, and pauses were all over 0.9 with p values for reliability <0.001. Compared to a conventional system, a novel system demonstrated significantly lower signal noise (median 0.3% [0.1-1.6%] vs. 2.4% [1.4-3.7%], p<0.001) and fewer episodes of signal loss (median 22 [2-53] vs. 64 [22-112] episodes, p=0.002). Conclusions: The novel telemonitoring system using a single-lead ECG patch offers performance comparable to that of a conventional system while significantly reducing signal loss and noise.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제30권6호
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• pp.567-571
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• 2008

Purpose: The purpose was to assess the usefulness of midazolam in patients undergoing minor oral surgery under conscious sedation. Materials and methods: Bispectral index was examined in 20 patients receiving oral minor surgery with conscious sedation supplemented with local anesthesia. All patients included were ASA I and had no contraindications to the study medications. The patients were escorted to the day surgery operation room where, before the commencement of the sedation and surgical procedures, routine monitoring was applied, including the noninvasive monitoring of arterial blood pressure, arterial oxygen saturation, and 3-lead electrocardiogram (Electrocardiogram). Bispectral index electrodes were applied on the frontotemporal region after cleansing the skin with alcohol. Bispectral index was calculated with the Electrocardiogram monitor (A-2000; Aspect Co.). Midazolam was then titrated (initially 3mg wait 2min and 2mg). Vital sign and Bispectral index checked every 5 minute until the end of the procedure. The results were then compared. Results: The Bispectral index index values throughout the sedation study period alter many level. The index was dropped at 5 minutes after administration, but raised at injection and odontomy procedure. During the operation, mean Bispectral index index was higher than conscious sedation index range($60{\sim}80$). The amnesic effect was shown 17 cases out of 20 cases(85%). Conclusion: Conscious sedation technique using midazolma is a safe and effective method of controlling behavior in oral and maxillofacial surgery.

• Journal of Electrical Engineering and Technology
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• 제11권5호
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• pp.1509-1518
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• 2016

• 한국정보컨버전스학회논문지
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• 제6권2호
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• pp.45-49
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• 2013

다른 생체신호와 마찬가지로 심전도(ECG) 신호도 측정시 백색잡음이 발생한다. 백색잡음을 효과적으로 제거하여 심장 관련 진단의 정확도를 높이고자 하였다. 심전도 신호에 백색잡음을 발생시켜 샘플링 신호를 만들었다. 웨이블릿 변환과 문턱치를 이용하여 잡음을 제거하였다. 신호대잡음비(SNR)를 이용하여 제거된 잡음을 수치적으로 비교하였다. 신호대잡음비 비교한 결과 SURE 방법은 3, 5dB에서 5.9531, 4.9301로 가장 좋은 결과를 나타내었고, uninversal 방법은 7, 9dB에서 3.6590, 1.9698로 가장 좋은 결과를 나타내었다. 문턱치를 이용한 잡음 제거시 잡음을 효과적으로 제거할 수 있었다. 심전도를 이용한 심장질환 진단에 정확도를 높일 수 있을 것으로 기대된다.

• 한국산업정보학회논문지
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• 제20권3호
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• pp.87-93
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• 2015

졸음 운전 등 운전자의 상태 변화에 따른 자동차 사고가 급증하고 있으며 이를 방지하기 위한 시스템 구축 및 운전자의 상태를 판단하는 알고리즘 개발이 요구되어 지고 있다. 본 논문에서는 모의 주행 시스템을 통한 운전자의 심박변이도, 산호 포화도 (SPO2), 체온을 측정하여 운전자의 상태를 알려 주는 실험을 수행하였다. 즉, 심박변이도 (Heart rate variability, HRV) 분석을 위해 운전자의 심전도(Electrocardiogram, ECG) 신호를 획득 한 후 심전도 P,QRS, T 파형 중 R peak 을 자동으로 검출하였고 이를 통해 구한 R-R interval을 이용하여 HRV의 주요 파라메타를 시간영역(time domain)으로 해석하여 작업 환경에 따른 운전자의 상태를 비교 분석하였다.

• 한국전자통신학회논문지
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• 제10권4호
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• pp.521-526
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• 2015

개인의 신원을 확인하기 위해 인간의 생물학적 특성을 사용하는 방법에 대한 연구가 활발히 진행되고 있다. 심전도를 이용한 생체 인식 기술은 피험자에 피부자극을 일으키지 않고 위조가 어렵다. 기존의 생체 인식 시스템인 지문, 얼굴 등의 인식시스템과 쉽게 접목이 가능하여 다중 생체 인식 시스템으로 응용할 수 있다. 본 논문에서는 이산 웨이블릿 변환 계수를 사용한 심전도의 파형 특성분석법으로 개인을 식별하는 방법을 제안하였다. 심전도 신호의 특징추출은 총 9개의 이산 웨이블릿 변환 계수를 대상으로 상관 계수 분석으로 수행하였다. 식별은 각 클래스의 특징벡터를 입력으로 오류 역전파 신경망을 적용하여 수행하였다. MIT-BIH QT 데이터베이스내 24명의 심전도에 대해 98.88%의 식별율을 나타냈다.

• 한국의류산업학회지
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• 제14권6호
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• pp.1010-1017
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• 2012

This study examined the clothing wearing comfort of elderly women by electroencephalogram (EEG) and electrocardiogram (ECG) analyses. This study utilized 7 elderly individuals aged 65 or more. Two kinds of clothing ensemble (control and prototype) were used as experimental clothing. The control consisted of a general clothing ensemble and the prototype consisted of clothing that added an extra gap. Subjects wore the control or prototype from 9:00 to 21:30 and EEG and ECG signals were measured in the last 30 minutes. The EEG analysis showed that relative band power of a and ${\alpha}$/high ${\beta}$ were higher when they wore the prototype rather than the control. The ECG analysis showed that absolute band power of HF was higher; however, absolute band power of LF and LF/HF was lower when they wore the prototype rather than the control. Subjects felt less stressful and more comfortable when they wore the prototype. The results demonstrate the necessity to develop clothing in consideration of the body changes in elderly women. It is significant that the assessment of wearing comfort was aided by the use of EEG and ECG analysis in the field of clothing and textiles.

• 대한의생명과학회지
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• 제17권4호
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• pp.313-319
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• 2011

Diabetes mellitus (DM) leads to a variety of complications and thus we have retrospectively studied to investigate problems of nerve conduction velocity (NCV) study and the heart in the patients with type-II DM. Blood glucose and blood pressure levels were higher in DM group than in Non-DM group. We found that several latencies were delayed in motor conduction study of upper (median and ulnar nerve) and lower extremities (peroneal and tibial nerve), whereas amplitudes and NCVs were decreased in DM group compared with Non-DM group. Latencies of sensory conduction study in upper and lower extremities (sural nerve) were delayed, while amplitudes and NCVs were lower in DM group than in Non-DM group. Abnormal percent of the electrocardiogram was higher in DM group than in Non-DM group. This retrospective study suggests that type-II DM can cause a damage effect on the peripheral nerve and the heart function.

• JSTS:Journal of Semiconductor Technology and Science
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• 제10권4호
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• pp.309-315
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• 2010

A fully-differential low-voltage low-power electrocardiogram (ECG) amplifier by using the nonfeedback PMOS pseudo-resistors is proposed. It consists of two operational-transconductance amplifiers (OTA) in series (a preamplifier and a variable-gain amplifier). To make it insensitive to the gate leakage current of the OTA input transistor, the feedback pseudo-resistor of the conventional ECG amplifier is moved to input branch between the OP amp summing node and the DC reference voltage. Also, an OTA circuit with a Gm boosting block without reducing the output resistance (Ro) is proposed to maximize the OTA DC gain. The measurements shows the frequency bandwidth from 7 Hz to 480 Hz, the midband gain programmable from 48.7 dB to 59.5 dB, the total harmonic distortion (THD) less than 1.21% with a full voltage swing, and the power consumption of 233 nW in a 0.13 ${\mu}m$ CMOS process at the supply voltage of 0.7 V.

• 대한의용생체공학회:의공학회지
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• 제31권5호
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• pp.365-374
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• 2010

This paper is about the personal identification algorithm using an ECG that has been studied by a few researchers recently. Previously published algorithm can be classified as two methods. One is the method that analyzes ECG features and the other is the morphological analysis of ECG. The main characteristic of proposed algorithm uses together two methods. The algorithm consists of training and testing procedures. In training procedure, the features of all recognition objects' ECG were extracted and the PCA was performed for morphological analysis of ECG. In testing procedure, 6 candidate ECG's were chosen by morphological analysis and then the analysis of features among candidate ECG's was performed for final recognition. We choose 18 ECG files from MIT-BIH Normal Sinus Rhythm Database for estimating algorithm performance. The algorithm extracts 100 heartbeats from each ECG file, and use 40 heartbeats for training and 60 heartbeats for testing. The proposed algorithm shows clearly superior performance in all ECG data, amounting to 90.96% heartbeat recognition rate and 100% ECG recognition rate.