• 한국태양에너지학회 논문집
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• 제26권1호
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• pp.21-28
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• 2006

Changes in building construction methods and repairing of older buildings have reduced infiltration rate. Synthetic materials, release airborne particles and uneven healthy odor are increased. For preventing pollutants introduce fresh outdoor air into the building, simply letting fresh outdoor air into building, however, Is not a cost-effective way to ventilation. When additional ventilation is added to an existing HVAC system, the heating and cooling equipment, often cannot handle the increased load. A HRV provides a way to minimize in energy costs while introducing fresh air to a building. In this study, the economical research of HRV, made of three types of materials, are conducted. Heat recovering characteristics are studied at seasonal outdoor air conditions based on the outdoor air property condition at, Seoul in 2002. As a results, the average sensible effectiveness is 0.75 in the sensible heat exchanger and average total effectiveness is 0.65 in the total heat exchanger. The pay back period of the sensible heat exchangers are $3.2{\sim}3.5$ year and it of total heat exchanger is 2.2 years.

• 전기학회논문지
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• 제66권3호
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• pp.581-586
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• 2017

The well-known Integral Pulse Frequency Modulation (IPFM) cardiac oscillator has been used to generate the heart beat fluctuations as a representation of the modulatory autonomic nervous activity in terms of sympathetic and parasympathetic state. The IPFM model produces heartbeats by integrating the modulated sinusoid signals and applying the threshold of unity or chaotic threshold levels. This study aims at evaluating the performance of IPFM model by analyzing the influence of the threshold level with comparatively applying preset threshold of unity and Logistic-map and Henon-map chaotic-threshold. Based on our simulated results with interpreting the spectral features of Heart Rate Variability (HRV), we can conclude that the IPFM model with preset threshold level of unity can generate the optimal heartbeat variations int the sense of clinically valid heartbeats.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2022년도 추계학술대회
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• pp.3-3
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• 2022

배경: 독일 크나이프 요법을 국내에서 적용하기 위해 검증 연구가 필요하다. 목적: 국내 산림 환경에서 적용한 크나이프 요법이 자율 신경계 및 회복탄력성에 미치는 영향을 규명하기 위함이다. 방법: 크나이프 요법 중 4가지 요소('움직임', '삶의 질서', '음식 섭취', '치유 식물')를 고려한 중재 프로그램을 구성하여, 성인 40명을 대상으로 적용했다. 중재 전과 후에 맥파측정기(uBioMacpa)를 이용하여 HRV(TP, VLF, LF, HF, LF/HF, CSI: Cumulative Stress Index)와 회복탄력성 지수를 측정하고 비교 분석했다. 결과: HRV를 분석한 결과, 프로그램 중재 후 연구 대상자의 TP(8.64%, p<.001), VLF(6.96%, p<.05), LF(15.86%, p<.001), HF(8.46%, p<.01), LF/HF(5.77%, p<.05)는 유의하게 증가하였고, CSI는 유의하게 감소하였다(16.06% p<.001). KRQ-53 평균 점수는 191.56점에서 206.22점으로 14.66점 증가한 것으로 나타났다. 결론: 국내 산림 환경에서 적용한 크나이프 요법은 자율신경계를 전체적으로 활성화하고, 교감과 부교감신경의 활성도를 높여 심장 활동을 촉진시키며, 누적 스트레스를 감소시켜 주었다. 그리고 회복탄력성을 개선하는 것으로 나타났으며(p<.05), 특히 자기 조절 능력 요인에서 그 효과가 큰 것으로 확인되었다. 본 연구의 결과는 크나이프 요법이 국내 산림 환경에서 치유 프로그램으로 활용되어 스트레스 해소를 포함한 자율 신경계의 긍정적인 효과를 제시한 초기적인 최초의 증거라 할 수 있다.

• 동의신경정신과학회지
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• 제19권3호
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• pp.45-54
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• 2008

Objective: To treat psychogenic headache patients, doctors have to amplify on the headache caused by emotional stress to patients, and assist the patients to cope with difficulties. So, we investigated HRV of the headache patients caused by Chiljungsang and would like to apply to the clinical treatment. Method: Our study measured time and frequency domain HRV indicies(5-min resting study) of 123 headache patients caused by emotional stress. Standardized tests of HRV allow a quantitative estimation of autonomic nervous system function. Results & Conclusions: 1. The study classed as aspects of the head pain showed the differences in RMS-SD(square root of mean squared difference of successive NN intervals) band, HF(high frequency) band significantly. 2. The male headache patients showed higher all the indicies except heart rate compared to the female patients, significantly in SDNN(standard deviation of NN interval), TP(total Power), HF band. 3. As the patients grow older, SDNN, RMS-SD band was lower and LF(low frequency) band, LF/HF ratio higher significantly. The beginning age lower, SDNN, RMS-SD band was higher significantly. The duration of the disease longer, LF band, LF/HF ratio was higher significantly.

• 대한한방부인과학회지
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• 제25권2호
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• pp.120-130
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• 2012

Objectives: The purpose of this study is to investigate the symptoms accompanied with acne and HRV pattern of the acne patients. Methods: We reviewed 60 acne patients(age 15-38) who visited ${\bigcirc}{\bigcirc}$ hospital from January 2010 to October 2011. We investigated the symptoms accompanied with acne of 60 patients and evaluated HRV of 41 acne patients. The data were analyzed by Mann-Whitney test using SPSS/PC ver 13.0 program. Results: 1. Prevalence of female post-adolescent acne was 66.7% in this study. The symptoms accompanied with acne were dischezia(35%), gastric discomfort(28.3%) in all patients and dysmenorrhea(40%), leukorrhea(38%), irregular menstrual period (24%) in female patients. 2. SDNN, RMSSD, VLF and HF of female were significantly lower than male. 3. SDNN, TP and VLF of un-dysmenorrhea group were significantly lower than dysmenorrhea group. 4. PSI of under 6 months group was significantly higer than over 6 months group. 5. In postadolescent acne patients SDNN, RMSSD, TP, LF and HF were significantly lower and PSI was significantly higher than adolescent acne patients. Conclusions: There are many female post-adolescent acne pateints and the assessment of the symptoms accompanied with acne and stress degree is helpful in treating acne. The further research and development about the diagnostic and therapeutic methods of acne are needed in oriental obstetrics and gynecology field.

• 대한한의학회지
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• 제28권1호통권69호
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• pp.105-116
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• 2007

Objectives : Mahuang (Ephedra sinica), well known as an herbal medicine in the East and West, contains a relatively high percentage of ephedrine known as sympathomimetic alkaloid. We investigated the effects of Mahuang on sympathetic nervous system with heart rate variety (HRV). Time and frequency domain analysis of HRV is a noninvasive technique capable of providing information on autonomic modulation of the sinus node. Methods : We investigated 57 healthy volunteers consisting of 37 subjects in the Mahuang group and 20 subjects in the placebo group. Study form was a randomized, placebo-controlled, double-blind clinical trial. The 37 subjects in the Mahuang group took 3 Mahuang capsules (1 capsule equivalent to 2g herb Mahuang) twice a day at 10 a.m. and 2 p.,., while the 20 subjects in the placebo group took 3 placebo-capsules filled with glutinous rice powder at the same times. Mahuang medicine and placebo medicine were made into opaque capsules. We measured HRV at 3 p.m. 1 or 2 days before medication and at 3 p.m. after medication. Results : Mean-RR and SDNN of the Mahuang group significantly decreased compared with that of the placebo group, but the heart rate of the Mahuang group significantly increased compared with the placebo. HRV-Index, RMSSD and SDSD of the Mahuang group significantly decreased compared with that of the placebo group, but PNN50 of the Mahuang group significantly increased compared with placebo. Ln(TP), Ln(VLF), Ln(LF) and Ln(HF) of the Mahuang group significantly decreased compared with those of the placebo group. There were no significant differences in normalized LF, normalized HF and LF/HF ratio between the Mahuang and placebo groups. Conclusion : The results suggest that Mahuang in healthy adults tends to reduce the autonomic nervous system within the normal range.

• 한국정밀공학회지
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• 제25권6호
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• pp.108-115
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• 2008

The wear on engine valve and seat insert is one of the most important factors affecting engine performance. The engine valve and seat insert must be able to withstand the severe environment that is created by: high temperature exhaust gases generated while the engine is running, rapid movement of the valve spring, high pressure generated in the explosive process. In order to study such problems, a simulator has been developed to generate and control high temperatures and various speeds during motion. The wear simulator is considered to be a valid simulation of the engine valve and seat insert wear process with various speeds during engine activity. This work focused on the test of various degrees of wear on four different exhaust valve materials such as HRV40, HRV40-FNV (face nitrided valve), STL #32, STL #6,. Throughout all tests performed in this study, the outer surface temperature of the seat insert was controlled at $350^{\circ}C$, the cycle number was $4.0{\times}10^6$, the test load was 6860 N, the fuel was LPG the test speed was 20 Hz (2400 RPM) and the seat insert material was HVS1-2. The mean (standard deviation) maximum roughness of the exhaust valve and seat insert was $25.44\;(3.16)\;{\mu}m$ and $27.53\;(3.60)\;{\mu}m$ at the HRV40, $21.58\;(2.38)\;{\mu}m$ and $25.94\;(3.07)\;{\mu}m$ at the HRV40-FNV, $36.73\;(8.98)\;{\mu}m$ and $61.38\;(7.84)\;{\mu}m$ at the STL #32, $73.64\;(23.80)\;{\mu}m$ and $60.80\;(13.49)\;{\mu}m$ at the STL #6, respectively. It was discovered that the maximum roughness of exhaust valve was lower as the high temperature hardness of the valve material was higher under the same test conditions such as temperature, test speed, cycle number, test load and seat insert material. The set of the HRV40-FNV exhaust valve and the HVS1-2 seat insert showed the best wear resistance.

• 대한한방내과학회지
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• 제29권2호
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• pp.443-455
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• 2008

Objectives : This study was designed to research whether HRV can yield a suitable diagnosis for activity of autonomic nerve system on functional dyspepsia. Methods : The testing of HRV was carried out at the Oriental Medical Center of Dong-Eui University with the participation of 28 functional dyspepsia patients, 25 dyspepsia caused by organic disease patients and 33 control group people. We checked HRV of the three groups for 5 minutes and compared HRV index(frequency domain analysis: HF, LF, VLF, LF/HF Ratio, TP) between groups. Results were as follows : 1. In the frequency domain analysis, HF, LF, VLF, and TP were significantly lower than the control group in the functional dyspepsia patients and dyspepsia caused by organic disease groups. HF, LF, VLF, LF/HF ratio, and TP were not significantly different between functional dyspepsia group and dyspepsia caused by organic disease group. 2. Age in dyspepsia patient group was significantly higher than in the control group. 3. In the frequency domain analysis, LF, VLF, and TP were significantly lower in the functional dyspepsia group than the control group in age 20-30 years. HF, LF, VLF, LF/HF ratio, and TP were not significantly different between the control group and dyspepsia caused by organic disease group in ages 20-30 years. HF, LF, VLF, LF/HF ratio, and TP were not significantly different between functional dyspepsia group and dyspepsia caused by organic disease group in age 20-30 years. Conclusion : According to this study, autonomic nerve system and parasympathetic nerve system decreased more in the functional dyspepsia patient group compared with the control group.

• 대한한의진단학회지
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• 제10권2호
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• pp.88-103
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• 2006

Objectives : We performed this study to search the best time for HRV measuring and which index has the validity in a short term measuring. Methods : At first, three examiner measured electrocardiogram(ECG) of 5 people(4 male + 1 female) for 20 minutes in two times. and we devided ten regions (0-5, 5-10, 10-15, 15-20, 0-10, 0-15, 0-20, 5-15, 10-20, 5-20 minutes). After that we finded the HRV index for each regions. To evaluate the validity, we used Gage Repeatability and Reproducibility Study by MINITAB(ver. 13.20). If the '%Study Var' is under 30 and 'Number of Distinct Categories' is over 4, we could tell it has validity(repeatability and reproducibility). Results : 1) The region and HRV index has repeatability and reproducibility, was HF index in 10-15 minutes. The HF index in 15-20 minutes gained 27.41(%Study Var) and 5(Number of Distinct Categories). 2) The HF index in 10-15 minutes has the better reproducibility than repeatability. The value of measurement is under the control. There is consistency among the examiner. The distribution of measurement is not large. There is no interaction between examiner and each people. 3) The HF index in 10-15, 0-10, 0-15, 0-20, 10-20 minutes was not enough to gain the repeatability and reproducibility. But it had some meanings ; %Study Var, Number of Distinct Categories is 32.68, 4 for 10-15 minutes, 34.43, 4 for 0-10 minutes, 34.44, 4 for 0-15 minutes, 33.56, 4 for 0-20 minutes, 32.07, 4 for 10-20 minutes. Conclusions : This study shows the best index of measuring HRV is the HF index in 15-20 minutes. So, from now on we should measure the HRV for 20 minutes and extract the HF index in 15-20 minutes. It must be the standard for HRV measuring.

• 대한한의진단학회지
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• 제9권2호
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• pp.94-109
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• 2005

Objectives: This paper investigated the effects of 8 Constitution Acupuncture on Heart Rate Variability(HRV) and is intended to find out 8 Constitutional difference on Autonomous Function after 8 Constitution Acupuncture stimulation. Methods: The subjects were comprised of 42 volunteers(11 men and 31 women). The volunteers had acupunctured by 8 Constitution Acupuncture Therapy. HRV and Mean Heart Rate(MHR) were measured by TAS9v2.0(IEMBIO & Saerom, Korea) on two times: before and immediately after acupuncture stimulation. The SPSS 13.0 for windows was used for statistical analysis: Mann-Whitney U-test, Paired Samples T -test and Wilcoxon signed rank test were used to verify the results. Results: 1. There was no statistically significant difference on HRV and MHR between Sympathicotonia and Vagotonia before acupuncture. 2. In the whole subject, immediately after acupuncture stimulation, MHR showed a significant decrease(p<0.01) and Ln(TP), Ln(LF) and Ln(HF) showed a significant increase(p<0.05). But there was no significant difference in LHR. 3. Immediately after acupuncture stimulation, MHR showed a significant decrease and Ln(TP), Ln(HF), showed a significant increase in Pulmotonia(p<0.05), Ln(TP) showed a significant increase in Pancretonia(p<0.05),MHR showed a significant decrease and Ln(TP) showed a significant increase in Hepatonia(p<0.05), and MHR showed a significant decrease and Ln(TP), Ln(HF), showed a significant increase in cholecystonia(p<0.05). But there were no significant difference on HRV and MHR in Colonotonia and vesicotonia. Conclusion: The results suggest that 8 Constitution Acupuncture is associated with changed activity in sympathetic and parasympathetic nervous system. Further study is needed for investigating the effects of 8 Constitution Acupuncture on HRV and autonomic nervous system.