• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1997년도 가을 학술발표회 논문집
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• pp.73-79
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• 1997

It is one of classical problems in the elastic theory to analyze contact stresses between elastic bodies. Concrete pavements under traffic wheel loads can be considered as one of these typical Problems. In the paper, Mindlin plate theory is used to consider the transverse shear effect, 8-node isoparametric plate bending element is adopted in this study, and an elastic plate resting on tensionless elastic half-space is analyzed by finite element method. The Boussineq's solution of elastic half-space is used to evaluate the flexibility of foundation. To obtain the boundary of contact area, the flexibility matrix of foundation is modified after each cycle of analysis iteratively. A Numerical example is presented by using these method.

• Structural Engineering and Mechanics
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• 제75권6호
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• pp.701-711
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• 2020

This papers studies nonlinear stability and post-buckling behaviors of geometrically imperfect metal foam doubly-curved shells with eccentrically stiffeners resting on elastic foundation. Metal foam is considered as porous material with uniform and non-uniform models. The doubly-curved porous shell is subjected to in-plane compressive loads as well as a transverse pressure leading to post-critical stability in nonlinear regime. The nonlinear governing equations are analytically solved with the help of Airy stress function to obtain the post-buckling load-deflection curves of the geometrically imperfect metal foam doubly-curved shell. Obtained results indicate the significance of porosity distribution, geometrical imperfection, foundation factors, stiffeners and geometrical parameters on post-buckling characteristics of porous doubly-curved shells.

• Journal of Cardiovascular Imaging
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• 제26권4호
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• pp.189-200
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• 2018

Pulmonary hypertension (PH) is defined as resting mean pulmonary artery pressure ${\geq}25mmHg$ and is caused by multiple etiologies including heart, lung or other systemic diseases. Evaluation of right ventricular (RV) function in PH is very important to plan treatment and determine prognosis. However, quantification of volume and function of the RV remains difficult due to complicated RV geometry. A number of imaging tools has been utilized to diagnose PH and assess RV function. Each imaging technique including conventional echocardiography, three-dimensional echocardiography, strain echocardiography, computed tomography and cardiac magnetic resonance imaging has-advantages and limitations and can provide unique information. In this article, we provide a comprehensive review of the utility, advantages and shortcomings of the multimodality imaging used to evaluate patients with PH.

• Journal of Preventive Medicine and Public Health
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• 제33권3호
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• pp.343-348
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• 2000

Objectives : This study was conducted to integrate the results of studies assessing the association between chronic noise exposure and blood pressure. Methods : Using a MEDLINE search with noise exposure, blood pressure and hypertension as key words, we retrieved articles from the literature that were published from 1980 to December 1999. The criteria for quality evaluation were as follows: 1) the study subjects must have been workers employed at a high noise level area 2) The paper should use average and cumulative noise exposure as method for exposure evaluation. 3) Blood pressure in each article should be reported in a continuous scale Among the 77 retrieved articles, six studies were selected for quantitative meta-analysis. Before the integration of the regression coefficients for the association between blood pressure and noise level, homogeneity tests were conducted. Results : All studies were a cross-sectional design and the study subjects were industrial workers. Five papers used a time-weighted average for noise exposure and only one paper calculated the cumulative noise exposure level. The measurement of blood pressure in the majority of studios were accomplished in a resting stale, and used an average of two or more readings. The homogeneity of studies was rejected in a fixed effect model, so we used the results in a random effect model. The results of the quantitative meta-analysis, the weighted regression coefficient of noise associated with systolic blood pressure and diastolic blood pressure were 0.05 (95% confidence interval [CI]: -0.03, 0.13) and 0.06 (95% CI: -0.01, 0.13), respectively. Conclusions : Our results suggested that chronic exposure to industrial noise does not cause elevated blood pressure.

• Tuberculosis and Respiratory Diseases
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• 제51권6호
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• pp.570-578
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• 2001

연구배경 : 만성폐쇄성폐질환 환자의 체중감소는 질환자체의 자연경과로 이해하고 있었으나, 체중이 감소된 환자들은 다른 질환에 대한 이환율이 증가하고, 폐성심이나 심부전으로 진행하는 경우가 많아 환자의 예후를 결정하는데 있어 중요한 요인으로 생각하게 되었다. 저자들은 생체전기 저항법률 이용하여 만성폐쇄성폐질환 환자의 영양결핍 정도와, 영양결핍과안정시 폐기능과의 관계를 알아보았다. 대상 및 방법 : 만성폐쇄성폐질환으로 입원한 중등도 혹은 중증 환자를 대상으로 급성기에 나타나는 증상이 호전된 후 퇴원하기 직전에 안정시 폐기능, 동맥혈 가스분석, 호흡 근육 강도, 그리고 체성분 분석을 시행하였다. 체생분분석 결과를 영양결핍과 정상상태로 구분하고 이 두 집단의 안정시 폐기능을 비교하였다. 결 과 : 대상 환자의 59%가 영양결핍 상태였으며, 저체증과 제지방량 결핍이 동시에 있는 경우가 31%이었다. 저체중만 있는 경우가 22%이였으며 제지방량 결핍만 있는 경우는 6%로, 전체 환자의 53%가 저체중이었고 37%의 환자가 제지방량 결핍이었다. 1초간 노력성 호기량 및 노력성 폐활량은 영양상태에 따라 차이가 없었으나, 최대호기유량은 영양겹핍환자가 유의하게 낮았다(p<0.05). 기도저항 및 폐 확산능, 그리고 최대흡기압 역시 영양결핍환자가 정상 환자보다 훨씬 낮았다(p<0.05). 동맥혈 산소분압 및 이산화탄소분압은 두 집단사이에 차이가 없었으며, 잔가량 및 총폐용량은 영양상태에 따라 차이는 없었으나, 영양결핍 환자들이 낮은 경향이었다. 결 론 : 영향결핍은 폐기능저하와 밀접한 관계가 있으며, 만성 폐쇄성폐질환 환자의 예후를 결정하는데 중요하게 작용할 것으로 생각된다. 또한 만성폐쇄성폐질환 환자의 치료에 기류제한의 완화 및 급성악화의 조절과 더불어 근육량 및 활동능력을 유지하기 위하여 영양학적인 측면을 고려하여야 할 것으로 생각된다.

• 한국의류학회지
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• 제38권4호
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• pp.440-454
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• 2014

This study examined the wearing effect of 3D compression suits on quantitative electroencephalogram (EEG) during walking and rest. Ten males in their 20s wore three types of experimental clothing, a loose-fit wear (BS), a 3D compression suit (3D CS), and a power film welded on CS (3D WCS); in addition, EEG signals were measured during resting, walking, after walking, and after sit-ups. The results showed that a higher pressure (due to 3D CS and 3D WCS) increased the 'Concentration' level and the 'Cognitive load' of brain waves during treadmill walking due to a higher cortex activity level when walking. Differentiation was shown between two compression suits and BS was enhanced during walking on a treadmill; however, the brain waves of 'Relaxation' between two compression suits were significantly different after walking, i.e., 'Relaxation' level of 3D WCS was the highest. Rigorous exercise such as sit-ups was inefficient to distinguish the effect of compression suits on EEG. Participants perceived a higher pressure due to compression suits; however, the wear comfort of two compression suits was maintained. Two compression suits were rated as supportive and helpful during walking. Various EEG parameters such as the indices of 'Relaxation', 'Concentration' and 'Cognitive load' were effective to observe the effect of 3D compression suits on wearers' brain waves during and after walking.

• The Korean Journal of Physiology and Pharmacology
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• 제17권6호
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• pp.499-503
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• 2013

This study tested the hypothesis that effects of the menstrual cycle on resting blood pressure carry over to dynamic exercise. Eleven healthy females were studied during the early (EP; low estrogen, low progesterone) and late follicular (LP; high estrogen, low progesterone) menstrual phases. Stroke volume (SV), heart rate (HR), cardiac output (CO), systolic blood pressure (SBP), diastolic blood pressure (DBP), and total vascular conductance (TVC) were assessed at rest and in response to mild and moderate cycling exercise during EP and LP. During EP, compared to LP, baseline SBP ($111{\pm}1$ vs. $103{\pm}2$ mmHg), DBP ($71{\pm}2$ vs. $65{\pm}2$ mmHg) and mean arterial pressure (MAP) ($84{\pm}2$ vs. $78{\pm}1$ mmHg) were higher and TVC ($47.0{\pm}1.5$ vs. $54.9{\pm}4.2$ ml/min/mmHg) was lower (p<0.05). During exercise, absolute values of SBP (Mild: $142{\pm}4$ vs. $127{\pm}5$ mmHg; Moderate: $157{\pm}4$ vs. $144{\pm}5$ mmHg) and MAP (Mild: $100{\pm}3$ vs. $91{\pm}3$ mmHg; Moderate: $110{\pm}3$ vs. $101{\pm}3$ mmHg) were also higher, while TVC was lower (Mild: $90.9{\pm}5.1$ vs. $105.4{\pm}5.2$ ml/min/mmHg; Moderate: $105.4{\pm}5.3$ vs. $123.9{\pm}8.1$ ml/min/mmHg) during EP (p<0.05). However, exercise-induced increases in SBP, MAP and TVC at both work intensities were similar between the two menstrual phases, even though norepinephrine concentrations were higher during LP. Results indicate that blood pressure during dynamic exercise fluctuates during the menstrual cycle. It is higher during EP than LP and appears to be due to additive effects of simultaneous increases in baseline blood pressure and reductions in baseline TVC.

• 한국엔터테인먼트산업학회논문지
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• 제14권4호
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• pp.401-409
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• 2020

본 연구는 테라테인먼트 물리적 요소를 적용하여 종아리 혈압, 발목 각도, 종아리 둘레에 미치는 영향을 알아보고자 하였다. 20대의 정상 여성 대학생을 대상으로 온열치료군(hot therapy group, 20명), 한랭 치료군(cold therapy group, 20명), 압박치료군(compression therapy group, 20명)으로 나누었다. 선행 논문을 근거로 하여 온열치료 20분, 한랭치료 15분, 압박치료 30분과 강도 100mmHg을 적용하였고, 왼쪽 다리에 적용 후 1시간 휴식을 취한 뒤 오른쪽 다리에 적용하였다. 각 군별로 종아리 혈압, 발목 각도, 종아리 둘레를 평가하였다. 본 연구결과, 온열 및 압박 치료에 종아리 혈압과 발목 각도의 적용은 혈압의 감소와 발목 각도의 증가에 유의한 효과가 있었으나(p<.05) 한랭 치료에서는 유의한 효과가 없었고, 모든 군에서 종아리 둘레의 부분에서는 통계학적으로 유의한 효과가 없었다. 따라서 종아리의 혈압의 감소와 종아리와 관련된 발목의 각도 증가를 위해서 온열치료와 압박치료를 권장하고, 다리에서 발생하는 여러 가지 문제점을 해결하는데 활용되길 기대한다.

• Journal of Preventive Medicine and Public Health
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• 제39권6호
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• pp.455-461
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• 2006

Objectives : Prolongation of the heart rate-corrected QT (QTc) interval has been reported to be associated with cardiovascular morbidity and mortality. However, few studies have examined the relationship between the QTc interval and cardiovascular risk factors in young healthy people, The aim of this study was to examine the associations between the QTc interval and cardiovascular risk factors in young healthy adults. Methods : This study was performed as part of the Kangwha study, which started in 1986, and is an on-going follow-up study on blood pressure and related cardiovascular risk factors. In follow-up examinations during 2005, cardiovascular risk factors, including anthropometrics, blood pressure, blood chemistry and carotid ultrasonography, were measured, and questionnaires on health behaviors completed by 127 men and 149 women aged 25 years. The QTc interval was measured on the resting 12-lead electrocardiogram using an automatic analysis program. Results : The mean QTc interval was significantly longer in women $(419{\pm}17ms)$ than in men $(405{\pm}17ms)$ (p<0.001). A significant positive correlation was found between the QTc interval and waist-hip ratio (p=0.030) in men. Women showed a positive correlation between the QTc interval and systolic blood pressure (p=0.017). On a multiple regression analysis, the QTc interval was positively associated with the waist-hip ratio in men (p=0.012) and with the systolic blood pressure (p=0.020) in women. Conclusions : In young healthy Korean adults, the QTc interval was independently associated with the waist-hip ratio in men and with the systolic blood pressure in women.

• 한국가구학회지
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• 제25권4호
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• pp.304-318
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• 2014

Bed for elderly and disabled, including the United States developed the industry Americas, and European countries, mainly in the production of products has dominated the world market. In large hospitals, and dependent products are sold at high prices. On the other hand, improvement of living standards of our country and to the advancement of residential culture of the demand for luxury products is increasing. The study of elderly Edition mattresses have been developed mainly in Europe to maximize the use of sleep can increase the efficiency of products has been studied. Due to the increase in elderly population Elderly Hospital, which is installed in the elderly silver town Edition requires the dissemination of the mattress in the bedroom several times a day resting and sleeping, eating, etc. Designing a variety of actions are needed. Edition of the elderly in Korea developed the design of bed with bed design and the manufacturer and the Institute for Ergonomics, welfare agencies and to build organic cooperation system under the direction of a professional designer to develop and you need to configure the space and the results of such actions by the distribution of cheap materials, ergonomic mattress for optimal development of behavior analysis to the need to promote the convenience of the user.