• 전기학회논문지
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• 제61권9호
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• pp.1340-1349
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• 2012

Increasing the oxidation of fat through exercise is the recommendable method for weight control. Preceding researches have proposed increase in the usage of fat during exercise in stabilized state and under maximum exertion through aerobic training. However, such researches require additional equipment for gas analysis in order to measure the caloric value or gas exchange of subjects during exercise. Such equipments become highly restrictive for those exercise and cause substantially higher cost. According to this, we have presented the method of estimating the maximal fat oxidation point through changes in LF & HF which reflects changes in heart rate and the autonomic nervous system in order to induce exercise for a less restrictive and efficient fat oxidation than existing methods. We have conducted exercise stress test on subject with similar exercise abilities, and have detected the changes in heart rate and changes in LF & HF by measuring changes in fat oxidation and measuring ECG signals at the same time through a gas analyzer. Changes in heart rate and HRV of the subjects during exercising was detected through only the electrocardiographic signals from exercising and detected the point of maximum fat oxidation that differs from person to person. The experiment was carried out 16 healthy males, and used Modified Bruce Protocol, which is one of the methods of exercise stress test methods that use treadmill. The fat oxidation amount during exercise of all the subjects showed fat oxidation of more than 4Fkcal/min in the exercise intensity from about 5 minutes to 10 minutes. The correlation between the maximal fat oxidation point obtained through gas analysis and the point when 60% starts to be relevant in the range from -0.01 to 0.01 seconds for values of R-R interval from changes in heart rate had correlation coefficients of 0.855 in Kendall's method and in Spearman's rho, it showed significant results of it being p<0.01 with 0.950, respectively. Furthermore, in the changes in LF & HF, we have determined the point where the normalized area value starts to become the same as the maximal fat oxidation point, and the correlation here showed 0.620 in Kendall and 0.780 in Spearma of which both showed significant results as p<0.01.

• 정신신체의학
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• 제30권1호
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• pp.7-15
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• 2022

연구목적 이 연구는 직장인의 스트레스 수준과 스트레스 취약성이 심박변이도(Heart rate Variability, HRV)에 미치는 영향을 파악하여 주관적인 스트레스와 심박변이도 기기를 통해 얻어진 객관적 스트레스 지표의 유의성을 확인하고 지역사회 정신건강사업에서 통합적 스트레스 측정도구로서의 효과성을 검토하고자 하였다. 방 법 2020년 6월부터 동년 7월까지 K병원에서 수행한 직장인의 스트레스 관리 및 정신건강증진 사업에 참여하고 연구에 동의한 대상자 929명의 기록 데이터베이스를 분석하였다. 일반적 특성과 스트레스 수준 및 스트레스 취약성이 심박변이도에 미치는 영향을 알아보기 위하여 다중선형회귀분석을 실시하였다. 결 과 일반적 특성 모두 SDNN (ln), RMSSD (ln), LF (ln), HF (ln)에 모두 유의한 영향을 주는 요소로 나타났지만 근무경력은 RMSSD (ln)에 유의한 영향을 미치지 않는 것으로 확인되었다. 스트레스 수준 및 스트레스 취약성은 심박변이도에 유의한 영향을 미치지 않았지만 스트레스 수준의 하위 요인인 스트레스 지각이 RMSSD (ln)에 유의한 영향을 주는 요인으로 확인되었다(β=0.118, p=0.023). 결 론 본 연구에서 스트레스 수준의 하위요인인 스트레스 지각이 RMSSD (ln)에 영향을 미치는 요인으로 나타났다. 이는 스트레스 상황에서 나타나는 부교감신경의 활성과의 관련성을 나타내는 것으로 지역사회 정신건강 현장에서 만성 스트레스 및 통합적 스트레스의 직접적인 지표로 평가하기에는 더 많은 후속 연구가 필요할 것으로 보인다

• Journal of Biosystems Engineering
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• 제38권2호
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• pp.163-170
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• 2013

Purpose: The purpose of this study is to provide analysis of physiological, biomechanical responses occurring from the operation to lifting or twist lifting task appears frequently in agricultural work. Methods: This study investigated the changes of physiological factors such as heart rate, heart rate variability (HRV) and biomechanical factors such as physical activity and kinetic analysis in the task of twisting at the waist while lifting. Results: Heart rates changed significantly with the workload. The result indicated that the workload of 2 kg was light intensity work, and the workload of 12 kg was hard intensity work. Physical activity increased as the workload increased both on wrist and waist. Besides, stress index of the worker increased with the workload. Dynamic load to herniated discs was analyzed using inertial sensor, and the angular acceleration and torque increased with the workload. The proposed measurement system can measure the recipient's physiological and physical signals in real-time and analyzed 3-dimensionally according to the variety of work load. Conclusions: The system we propose will be a new method to measure agricultural workers' multi-dimensional signals and analyze various farming tasks.

• 재활복지공학회논문지
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• 제10권2호
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• pp.163-170
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• 2016

본 연구에서는 삼림욕을 즐기는 것과 같은 편안한 상태의 휴식을 유도하기 위하여 편백나무를 이용하여 힐링 침대 시스템과 색체자극을 위한 LED 감성 모듈을 개발하였고, 8가지 조명과 3가지 색온도의 색체 자극에 따른 휴식이 스트레스 완화에 미치는 효과를 비교 분석하였다. 피험자는 건강한 20대 성인 남여 7명(age $23.3{\pm}0.7yr$; height $165{\pm};10cm$ body mass $59{\pm}10kg$)을 대상으로 하였으며, 8가지 색상(red, orange, yellow, green, blue, indigo, violet, white)과 3가지 색온도(3,000K, 5,000K, 8,000K)에 따른 휴식 시 심박변이도, 피험자의 주관적 인지평가를 진행하였다. 그 결과, 심박변이도의 경우 한색계열인 green, blue, indigo의 조명과 3000K의 낮은 온도 조명이 부교감신경을 활성화시켜 심리적으로 안정되는 결과를 얻었으며, 피험자가 주관적으로 느끼는 인지시간의 결과 동일 시간을 자극받았을 지라도 green 색상과 3,000K 온도 자극 시 인지 시간이 가장 느렸으며, 감성어휘 평가에서는 orange 색상과 3,000K온도에서 가장 높은 점수를 얻었다. 따라서, 본 연구 결과 3,000K의 낮은 온도자극과 green 색상 자극 시 심리정 안정이 가장 높은 결과를 얻었으며, 추후 연구에서는 작업 환경에 따른 조명 자극 시 피로도 회복과 뇌파 변화를 비교 분석 할 것이다.

• Journal of Preventive Medicine and Public Health
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• 제37권2호
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• pp.182-189
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• 2004

Objectives : The objective of this study is to compare the circadian patterns of heart rate variability assessed by 24-hour ambulatory electrocardiographic (ECG) recordings during day shift and night shift among the workers in the 5 days-concecutive-12-hour shift in an automobile factory in Korea. Methods : The study population consisted 300 workers, who were randomly selected among the 8700 total workers in one car factory. To analyse circadian variation, the 24-hour ECG recordings (Marquette) were measured during day shift (08:00-20:00 h) and night shift (20:00-08:00 h). Analysis was performed for all time and frequency domain measures of HRV. 233 workers completed taking 24-hour ECG recordings. Results : This study shows that the 24 hourcircadian variation mainly follows work/sleep cycle rather than day/night cycle among shift workers. This study also shows that among the night shift, the circadian variation between work and sleep cycle decreased compared to the work/sleep cycle among day shift workers. All time and frequency domain parameters (except LF/HF ratio) show significantly different between work and sleep in the day shift and night shift. Conclusion : These changes in heart rate variability circadian rhythms reflect significant reductions in cardiac parasympathetic activity with the most marked reduction in normal vagal activity among the shift workers. Especially, it suggests the circadian rhytm has blunted among the night workers. The quantification of the circadian variation in HRV can be a surrogates of workers' potential health risk, as well as suggests possible mechanisms through which the shift works compromise workers' health.

• 대한한방내과학회지
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• 제28권4호
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• pp.717-726
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• 2007

Objectives : This study was conducted to assess the effect of Uhwangchungsimwon on the autonomic nervous system. Methods : Eligible subjects were enrolled from healthy people in their 20s-30s. They were divided into two groups, the UC group (n=22) and the control group (n=20). We monitored ECG from 14:00 to 18:00 in both groups. In the UC group, subjects were administered UC at 15:00. HRV analysis was conducted at 14:00, 16:00, and 17:00 for 512 seconds. Results : The degree of LF/HF ratio change was significantly higher in the UC group at 1 hour after administration. Conclusion : We suggest Uhwangchungsimwon may be useful for stabilization of the autonomic nervous system by activating parasympathetic nerve in healthy people.

• 대한한방내과학회지
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• 제38권6호
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• pp.955-970
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• 2017

Objectives: The aim of this observational study was to identify and analyze the patterns to compare the characteristics of asthma patients. Methods: The subjects were 40 asthma patients who had satisfied the inclusion and exclusion criteria. They were divided into deficiency syndrome and excess syndrome groups, and cold syndrome and heat syndrome groups. Their quality of life was measured by the quality of life questionnaire for adult Korean asthmatics (QLQAKA) and VAS. Heart rate variability (HRV) was measured, and the degree of obesity was evaluated by body mass index (BMI). Hematological, biochemical, and immunoglobulin (Ig) E laboratory tests were included. Results: Based on pattern identification, the 40 asthma patients could be divided into two categories of groups: 1) the deficiency syndrome (N=18) and the excess syndrome (N=22) groups: 2) the cold syndrome (N=35) and the heat syndrome (N=5) groups. The mean value of HF differed significantly between the deficiency and excess syndrome groups. The mean value of IgE in blood tests of asthmatics was greater than four times the reference value. For BMI, the subjects were classified into three groups: normal weight (N=12), overweight (N=12), and obese (N=16). Conclusions: Development of a more accurate asthma-specific pattern identification tool could play a crucial role in asthma control. In addition, good control of asthma can improve the quality of life. Obesity is one of the factors associated with asthma exacerbation.

• Journal of Acupuncture Research
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• 제30권3호
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• pp.39-49
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• 2013

Objectives : The purpose of this study is to assess the effect of Taegeuk acupuncture on reducing mental stress by analyzing heart rate variability in Soeumin. Methods : Six Soeumin-diagnosed men participated in this study. They were randomly divided into group A and group B. Each participant went through 4 sessions every week with 1 week of washout period in between each session. HRV was measured three times at every session; at baseline, after administering mentally stressful circumstances and after applying Soeumin Taegeuk acupuncture or Soyangin Taegeuk acupuncture. This study was designed as a crossover clinical trial. Group A participants were treated with two sets of Soeumin Taegeuk and Soyangin Taegeuk acupuncture treatment in respective order (i.e. Soeumin Taegeuk - Soyangin Taegeuk - Soeumin Taegeuk - Soyangin Taegeuk acupuncture treatment). Group B participants were treated with reverse-ordered acupuncture treatment (i.e. Soyangin Taegeuk - Soeumin Taegeuk - Soyangin Taegeuk - Soeumin Taegeuk acupuncture treatment ). Bayesian analysis was performed by using WinBUGS(Ver. 1.4.3) for comparison between Soeumin Taegeuk acupuncture and Soyangin Taegeuk acupuncture. Results : Overall, Soeumin Taegeuk acupuncture tends to reduce LF/HF ratio, LF, HF, LF(Norm) and increase HF(Norm) more than Soyangin Taegeuk acupuncture, but the difference was not statistically significant. In one participant, however, Soeumin Taegeuk acupuncture reduced LF/HF ratio, LF(Norm) and increased HF(Norm) more than Soyangin Taegeuk acupuncture, and the difference was stastatistically significant. Conclusions : This study suggests that Soeumin Taegeuk acupuncture might be an effective means of stabilizing mental stress-induced imbalance of autonomic nervous system for Soeumin.

• 감성과학
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• 제17권3호
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• pp.29-38
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• 2014

본 연구에서는 LED 면조명을 이용한 감성조명시스템의 인체 생리학적 반응을 검증하였다. 실험은 시각 질환이 없는 건강한 20대 남성 10명을 대상으로 LED 면조명의 색상에 따른 인체의 반응을 평가하였다. LED 조명은 빨간색, 주황색, 노란색, 초록색, 파란색, 보라색, 무채색(하얀색)을 사용하여 5분간 조명 자극을 주었다. 평가 방법으로 심리적 상태를 분석하기 위하여 뇌파와 심박변이도를 평가하였고 피부의 온도 변화를 살펴보기 위해 체열을 평가하였다. 분석 결과 뇌파의 경우 무채색, 빨간색, 주황색 LED 면조명 자극 시 ${\alpha}$파 비율이 감소하였다. 또한 무채색, 빨간색, 주황색, 노란색 LED 면조명 자극을 받을 때 부교감신경에 비하여 교감신경이 활성화되고, 체열이 증가하였다. 이에 비해 초록색, 파란색, 보라색 LED 면조명 자극을 받을 때에는 ${\alpha}$파 비율의 증가와 교감신경에 비하여 부교감신경의 활성화가 발생하였고 체열이 감소하였다. 향후 각 색상을 조합하여 상황별 모드를 구성한 실험과 시각적 자극 외에 아로마와 같은 후각 자극, 음악과 자연의 소리를 이용한 청각 자극 등을 이용한 복합한 시너지 효과에 대한 연구가 필요할 것으로 사료된다.

• 한국컴퓨터정보학회논문지
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• 제29권3호
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• pp.137-146
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• 2024

이 연구는 전신 전기근자극 훈련이 비만 수준에 따른 여성의 신체조성 및 심박변이도에 미치는 영향을 분석하는 것이다. 연구 대상은 폐경 전 여성으로 BMI<25는 BMI-N(n=15), BMI=25~29.9는 BMI-1(n=16), BMI>30은 BMI-2(n=9) 집단으로 분류한 후, 12주간 주당 3회의 전신 전기근자극 훈련을 실시하였다. 실험처치 전·후 신체조성과 심박변이도를 측정하여 반복 이원 변량분석과 대응 표본 t-검정을 실시하였고, 사후검증은 Tukey의 방법을 사용하였다. 유의수준(α)은 0.5로 설정, 다음과 같은 결과를 얻었다. 첫째, Weight, BMI, FFM, FM은 BMI-2 집단이 가장 많이 감소하였고, BMI-1, BMI-N 집단 순으로 감소하였다. %BF와 VF는 BMI-2 집단이 가장 많이 감소하였다. 둘째, BPM은 모든 집단에서 차이가 나타났으며, BMI-2 집단이 가장 크게 감소하였다. SDNN과 RMSSD는 각 집단에서 차이가 나타났으며, 비만 수준에 따른 차이는 없었다. LF, HF 및 LF/HF 비율은 차이가 없었다. 결론적으로, 전신 전기근자극 훈련은 비만수준이 높은 여성들의 체구성 변화와 심장 순환계에 긍정적 효과를 미치는 운동요법이 될 수 있음을 확인하였다.