• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2002년도 제19회 학술발표대회 논문초록집
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• pp.37-40
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• 2002

The engine performance test was carried out to investigate the effects of breath and exhaust on the performance of a reciprocating engine for small aircraft. In this test, three valves to control flow areas of a inlet and two outlets were used, the engine manifold pressure and the static thrust of propeller were measured in nine breath/exhaust conditions. Generally, small variations on the performance were showed as the test conditions were changed. The manifold pressure was increased as flow area of the inlet or the outlet was decreased in normal condition, however it was decreased as both flow areas were decreased. The static thrust of propeller was showed similar as the manifold pressure.

• Advances in nano research
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• 제15권3호
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• pp.239-251
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• 2023

In the present study, we aim to use nanotechnology sensors/actuators to capture pressure and frequency of voice singers and to send signals for improving breathing pressure. In this regard, a circular composite structure having 3 different layers are used. The core layer is nano-composite material reinforced with graphene nanoplatelets. The face sheets are piezo electric materials connected to electrical circuit capable of measuring and applying voltage to the piezoelectric layers. This sensors have extremely smaller size than conventional sensors attached to the neck of singer and, hence, minimizes the influences on the output voice of the singer. A brief theoretical framework are presented for nonlocal strain gradient theory and geometry of the sensor is described in detail. The controlling procedure along with experimental results on 20 amateur and professional singer participants are also presented. The results of the study indicate that the participants could gain benefit from the device for improving their ability in phonation and keeping their frequency at a constant level although they have difficulty in the beginning of the experiment getting used to the device.

• 대한한방내과학회지
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• 제20권1호
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• pp.222-231
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• 1999

Uwhangchungsimwon(UC) has been used in the treatment of a wide variety of conditions including stroke, hypertension, arteriosclerosis, autonomic imbalance, mental instablity, etc in Korean traditional hospitals, In particular it is often initialy chosen for emergency care of acute stroke. The aim of this study was to evaluate the effect of UC on cerebral hemodynamics. Using transcranial Doppler ultrasound, we studied changes of mean flow velocity and pulsatility index(PI) of middle cerebral arteries (MCAs) from 11 health young volunteers who were administrated with 1 pill UC and 11 health controls who were not. We obtained hypercapnia with breath-holding and evaluated cerebrovascular reactivity with breath-holding index(BHI). Systolic blood pressure, diastolic blood pressure, and heart rate were measured using ambulatory blood pressure monitoring(ABPM). In UC administration group, the evaluation was performed during basal condition. and repeated at 20, 40, and 60 min after administration. In controls, the evaluation was performed at corresponding time intervals. Mean flow velocity in middle cerebral artery, systolic blood pressure, diastolic blood pressure, and heart rate did not change during the observation period and were not different between these two groups. However, administration of UC was associated with decreases in PI by $3.6{\sim}12.4%$ in BHI by $17.9{\sim}24.8%$ compared with pre-administration period. Decreases in PI and BHI with UC were significantly different compared with control group (p<0.05). These results indicate that UC decreases PI and BHI in cerebral artery, which is due to a dilation of cerebral resistance vessels.

• Physical Therapy Rehabilitation Science
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• 제12권3호
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• pp.251-258
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• 2023

Objective: The practice of breathing exercises involves altering the depth and frequency of respiration. Strengthening respiratory muscles plays a crucial role in maintaining overall health and well-being. The efficiency of the respiratory system affects not only physical activity but also various physiological processes including cardiovascular health, lung function, and cognitive abilities. The study evaluated the reliability of the developed device for inspiratory/expiratory training using pressure sensors and Bluetooth connectivity with a smartphone application. Design: Design & development research Methods: The research methodology involved connecting a custom-made respiratory sensor to an IMT-PEP BIC Breath device. Various pressure conditions were measured, and statistical analyses were performed to assess reliability and consistency. Results showed high Intraclass Coefficient Correlation (ICC) values for both inspiratory and expiratory pressures, indicating strong test-retest reliability. The device was designed for ease of use and wireless monitoring through a smartphone app. Results: This study conducted at expiratory pressure confirmed the proper operation of the IMT/PEP breathing trainer at the specified pressure setting in the product. The pressure sensor demonstrated high test-retest reliability with an ICC value of 0.999 for both expiratory and inspiratory pressure measurements. Conclusions: The developed respiratory training device measured and monitored inspiratory and expiratory pressures, demonstrating its reliability for respiratory training. The system could be utilized to record training frequency and intensity, providing potential benefits for patients requiring respiratory interventions. Further research is needed to assess the full potential of the device in diverse populations and applications.

• Annals of Clinical Neurophysiology
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• 제14권1호
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• pp.20-24
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• 2012

Background: Migraine patients can be sensitive to external or internal stimuli, such as light, noise, or hormonal changes. Using transcranial Doppler ultrasonography (TCD) with breath-holding method, we evaluated the changes of cerebrovascular reactivity (CVR) to hypercapnia in women with migraine without aura between fasting and postprandial period. Methods: Twelve women with migraine without aura and the same number of age and sex-matched healthy controls with no significant history of headache participated in this study. Using TCD examinations, we studied mean flow velocity in middle cerebral artery with better temporal window. Each subject was examined consecutively before and after a standard meal, together with serum glucose level and blood pressure. CVR was evaluated with breath-holding index (BHI). Results: Postprandial-BHI (mean+SD) was significantly higher than fasting-BHI (mean+SD) in patients group but not in controls (in patient group; postprandial-BHI=1.38, fasting-BHI=1.08, in control group; postprandial-BHI=1.25, fasting-BHI=1.18, P=0.021 and 0.239, respectively). After meal, serum glucose level was significantly enhanced but blood pressure was not in both groups. Serum glucose level of patients showed a tendency of mild positive correlation with BHIs (${\gamma}$=0.448, P=0.032). Conclusions: Although exact mechanisms are unclear, cerebrovascular reactivity of some women with migraine without aura may be influenced by prandial state.

• 통합자연과학논문집
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• 제1권2호
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• pp.122-126
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• 2008

The stress is an unavoidable result and a complex phenomenon in modern society. too, Human activity changes under control of the stress. The stress is a reaction to adrenalin or other stress hormones. It provides the power for fighting and the energy for going away from dangers. Because of the stress, our bodies increase the pulse, the blood pressure and the breath for more blood and more oxygen. So, in this research, we are measuring those which was increased by the stress. Also we will examine the change of HRV and APG on music. After that, in order to reduce the stress, we will design matching system that is based on the sense for music by using Zigbee.

• 대한지역사회영양학회지
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• 제3권3호
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• pp.358-367
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• 1998

The study purpose was to investigate psychosocial factors related to smoking among adolescent boys. The Theory of Planned Behavior provide the basis for the study. Twenty-five attitudinal beliefs, 9 normative beliefs and 20control beliefs were identified through questionnaire development. The data were analyzed using t-test and χ2-test. Thirty-three percent of 300 students were smokers. Most of the beliefs examined were significantly different between smokers(n=92) and nonsmokers(n=92). With respect to attitudinal beliefs, smokers responded less negatively on the items of bad health effects of smoking such as sore throat, headache, chest pain, risk of cancer and bad blood circulation(p<0.001), and decreased physical strength(p<0.05). Smokers believed less negatively on the items that smoking leads to bothering others, bad breath, yellow teeth and making them spend money(p<0.001). In contrast, smokers felt more positively on smoking as a means of stress management, relaxing, helping digestion(P<0.001). Smokers felt less pressure for not smoking from significant others. Especially mother, siblings, friends, girl friends, seniors of school were important sources of influence regarding subject's smoking. Smokers felt less confident in controlling the urge to smoke in several situations including; when they were with friends or asked to smoke by friends; after the meal, or drinking; when they were bored or stressed, upset, and when they felt unstable(p<0.001). Smokers also scored lower on specific skills to quit or control the urge to smoke as well as overall perceived control, compared to nonsmokers(p<0.001). These results suggest that interventions for adolescents incorporate diverse strategies to increase the perceived control over smoking in specific situations as well as overall perceived control, to help them realize and modify attitudinal beliefs, and to elicit support from significant others for not smoking. (Korean J Community Nutrition 3(3) : 358∼367,1998)

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2008년도 춘계종합학술대회 A
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• pp.894-897
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• 2008

스트레스는 현대 인간 문명사회에서의 피할 수 없는 결과이며 복잡한 현상이다. 또한 이의 통제 유무에 따라 인간의 활동능력은 심각한 변화를 받을 수 있다. 스트레스는 자극 호르몬인 아드레날린이나 다른 스트레스 호르몬이 혈중 내로 분비되어 우리 몸을 보호하려고 하는 반응으로 위험으로부터 싸우거나 멀리 피해버리는 힘과 에너지를 제공한다. 이러한 변화는 근유, 뇌, 심장에 더 많은 피를 보낼 수 있도록 맥박과 혈압을 증가시키고 더 많은 산소를 얻기 위해 호흡이 빨라지는 현상이 나타난다. 이에 본 논문에서는 스트레스를 통해 증가된 맥박과 혈압, 호흡수를 측정한 후 스트레스를 완화시키기 위한 방편으로 음악을 이용한 감성 기반 매칭 시스템을 설계한다. 음악에 따른 HRV와 APG의 변화율을 살펴보고 Zigbee를 이용하여 맥박, 혈압, 호흡수를 측정한 후 감성 음악을 기반으로 하여 스트레스를 완화시킬 수 있는 시스템을 제안한다.

• Journal of Nutrition and Health
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• 제32권8호
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• pp.908-917
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• 1999

This study was done to compare nutrient intakes, anthropometric indices, and psychosocial factors related to smoking by smoking status among adolescent girls in Seoul. Subjects were high school students, and smokers were 17.6%. Nutrient intakes were analyzed by convenient method, and anthropometric measurements were done by Inbody 2.0. Psychosocial factors of smoking were examined based on the Theory of Planned Behavior : 26 attitudinal, 9 normative, and 17 control beliefs were used. Smokers smoked 5-7 cigarettes a day on average, with 1.26 pack-years of smoking, There were no significant differences in anthropometric characteristics, except fat distribution, between smoking(n=92) and nonsmoking(n=92) and nonsmoking(n=94) group. The percentage of alcohol groups. Especially, caloric intake (63.6% of RDA) were much below the recommended level. With respect to psychosocial factors, 18 out of 26 attitudinal beliefs were significantly different between smokers and nonsmokers. Smokers responded less negatively on the items of bad health effects of relax(p<0.001). In addition, smokers were more convinced of advantages of smoking (test, etc.)but responded less negatively on the disadvantages of smoking(bothering others, yellow teeth, bad breath, etc.). Smokers expressed less pressure for not smoking from siblings, friends, school seniors than nonsmokers. In addition, smokers, expressed less confidence in controlling the urge to smoker or quitting smoking in several situations, such as 'after a meal', 'feel bored', 'with friends', 'when angry' offered a cigarette by friends', 'drinking coffee or tea', 'drinking alcohol', 'seeing others smoke'(p<0.001). Smokers also felt less developing in applying specific skills for controlling the urge to smoker or quitting smoking. These findings suggest the need for developing smoking cessation programs for adolescent females, focusing on specific beliefs identified in this study.

• 대한한방부인과학회지
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• 제27권1호
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• pp.140-151
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• 2014

Objectives: Cold hypersensitivity has been regarded to be associated with digestive function. This study is aims to evaluate the correlation between digestive function and coldness of hands. Methods: We made a research of 80 women who is in ${\bigcirc}{\bigcirc}$ University. The patients were subjected to thermometer, and those with thermal difference between upper arm and palm were diagnosed with cold hypersensitivity. The patients were divided into two group by cold hypersensitivity group (n=20), and non-cold hypersensitivity group (n=19), and 39 women are mesured by Nepean dyspepsia index-Korean version (NDI-K) to evaluate the severity of functional dyspepsia. Results: There was no difference between two groups on age, height, weight. In functional dyspepsia symptom score, 6 symptoms (Pain in upper abdomen, Burning in upper abdomen, Cramps in upper abdomen, Pressure in upper abdomen, Vomiting, Bad breath) out of 15 were significantly increased in cold hypersensitivity group compared with non-cold hypersensitivity group. And in quality of life score, 3 domains (Tension/sleep, Interference with daily activities, Knowledge/control) out of 5, and total quality of life score were significantly decreased in cold hypersensitivity group compared with non-cold hypersensitivity group. Conclusions: This study shows the correlation between cold hypersensitivity and digestive function.