• Nutrition Research and Practice
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• 제7권5호
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• pp.380-384
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• 2013

Zinc may participate in blood pressure regulation and in the pathogenesis of hypertension. The study examined the relationship between zinc status and blood pressure in obese Korean women. Forty obese women (body mass index (BMI) ${\geq}25kg/m^2$) aged 19-28 years participated in this study. Zinc intake was estimated from one 24 hour recall and 2-day diet records. Serum and urinary zinc concentrations were determined by atomic absorbance spectrophotometry. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured using an automatic sphygmometer. Metabolic variables, such as waist circumference, triglyceride, high density lipoprotein (HDL) cholesterol, fasting glucose, and fasting insulin, were also measured. Dietary zinc intake of obese women was averagely 7.5 mg/day. Serum zinc and urinary zinc concentrations were $13.4{\mu}mol/L$ and $378.7{\mu}g/day$, respectively. Averages of SBP and DBP were 119 mmHg and 78 mmHg. Dietary zinc intake was negatively correlated with SBP after adjusting for energy intake (P < 0.05), but serum and urinary zinc concentrations were not found to be correlated with SBP or DBP. Multivariate linear regression analysis showed that dietary zinc intake was inversely associated with SBP in obese women after adjusting for body weight, energy intake and sodium intake (P = 0.0145). The results show that dietary zinc intake may be an independent risk factor of elevated SBP in obese Korean women.

• 대한인간공학회지
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• 제24권4호
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• pp.23-30
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• 2005

The mailman's shoes should be designed in due consideration of occupational features they spend most of times to walk. For that reason, the shoes required functions to reduce the foot fatigue and to protect body by dispersing the body weight to the whole foot. In this research, for the functional improvement of the insole, insoles are investigated and analyzed by biomechanics experimentation. Under the base of these experimental results, we develop insoles that can reduce the body load and muscular-skeletal disorder. The pressures are concentrated on the metatarsus and heel by the result of analyzing pressure distributions of the using shoes. Accordingly, we offer the prototype functional insole that is ranked from high pressure to low pressure on the base of a shock absorb function. This prototype functional insole is examined for statistical significance by pressure distribution areas. The experimental results show that pressure areas are dispersed to whole foot, for this reason, pressures of the metatarsus and heel are reduced. Results of this research can not only improve the function of insoles which is suitable for occupational features, but also be a base on constructing data bases for biomechanics gait insoles.

• 대한기계학회논문집B
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• 제21권9호
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• pp.1174-1184
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• 1997

Extinction characteristics of pure hydrogen-oxygen diffusion flames, at high pressures in the neighborhood of the critical pressure of oxygen, is numerically studied by employing counterflow diffusion flame as a model flame let in turbulent flames in rocket engines. The numerical results show that extinction strain rate increases almost linearly with pressure up to 100 atm, which can be explained by comparison of the chain-branching-reaction rate with the recombination-reaction rate. Since contributions of the chain-branching reactions, two-body reactions, are found to be much greater than those of the recombination reactions, three-body reactions, extinction is controlled by two-body reactions, thereby resulting in the linearity of extinction strain rate to pressure. Therefore, it is found that the chemical kinetic behaviors don't change up to 100 atm. Consideration of the pressure fall-off reactions shows a slight increase in extinction strain rate, but does not modify its linearity to pressure. The reduced kinetic mechanisms, which were verified at low pressures, are found to be still valid at high pressures and show good qualitative agreement in prediction of extinction strain rates. Effect of real gas is negligible on chemical kinetic behaviors of the flames.

• Safety and Health at Work
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• 제8권2호
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• pp.212-219
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• 2017

Background: Low back pain (LBP) is a major problem for office workers. Individuals adopting poor postures during prolonged sitting have a considerably increased risk of experiencing LBP. This study aimed to investigate seat pressure distribution characteristics, i.e., average pressure, peak pressure ratio, frequency of postural shift, and body perceived discomfort (BPD), during 1 hour of sitting among office workers with and without chronic LBP. Methods: Forty-six participants (chronic LBP = 23, control = 23) typed a standardized text passage at a computer work station for an hour. A seat pressure mat device was used to collect the seat pressure distribution data. Body discomfort was assessed using the Body Perceived Discomfort scale. Results: Office workers with chronic LBP sat significantly more asymmetrically than their healthy counterparts. During 1-hour sitting, all workers appeared to assume slumped sitting postures after 20 minutes of sitting. Healthy workers had significantly more frequent postural shifts than chronic LBP workers during prolonged sitting. Conclusion: Different sitting characteristics between healthy and chronic LBP participants during 1 hour of sitting were found, including symmetry of sitting posture and frequency of postural shift. Further research should examine the roles of these sitting characteristics on the development of LBP.

• 한국가시화정보학회지
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• 제18권3호
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• pp.77-83
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• 2020

A uniflow cyclone has simple structure with a single channel in one direction. The one directional particle removal enables the uniflow cyclone to have compact size and low pressure drop. However, it has low collection efficiency compared to conventional cyclones. In this study, the effect of primary geometry on the performance of a uniflow cyclone with swirl vane is numerically investigated for the design of high performance uniflow cyclone. It is found that as the vortex finder diameter is increased, the pressure drop and the collection efficiency are decreased. Also, the same trend is predicted when the vortex finder height is increased. The best collection efficiency is predicted to be obtained when the vortex finder height is equal to the diameter of a cyclone. Reducing the body height by half will increase the pressure drop by 41%. When the body height is decreased, the collection efficiency is first increased and then decreased. The best collection efficiency is obtained when the body height is 4~5 times the cyclone diameter. Overall, the particle collection efficiency is highest when the Dν/D is equal to 0.3. But, the pressure drop is as high as 1592 Pa. Considering both collection efficiency and pressure drop, the best design is when Dν/D, Hν/D, and Hb/D are equal to 0.5, 1, and 5, respectively.

• 한국정밀공학회지
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• 제24권9호
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• pp.7-11
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• 2007

• 대한간호학회지
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• 제36권5호
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• pp.837-844
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• 2006

Purpose: This study was done to identify fat distribution and blood pressure according to anthropometric change patterns between NIDDM patients and control subjects. Methods: Cross-sectionally 167 NIDDM patients and 87 controls were studied. Previous maximal body weight and acute weight loss was obtained. Current height, body weight, BMI, waist-hip ratio(WHR), skinfold thicknesses(abdomen, subscapular & triceps), and blood pressure was measured. Three anthropometric change patterns were categorized by BMI changes from the maximum lifetim's BMI to the current time (obese-obese, obese-nonobese and nonobese-nonobese: obese: BMI$\geq$25kg/m$^2$, nonobese: BMI<25kg/m$^2$). The data was analyzed by $X^2$, t-test, age adjusted ANCOVA and Least Squares Means(LSM) for multiple comparison. Result: Acute body weight loss(p=0.01), anthropometric change types (p=0.001), WHR (p=0.05), and skinfold thickness (p=0.002) of NIDDM were significantly higher than those of the controls. The mean arterial pressure, WHR and skinfold thicknesses were greater in both obese-obese and obese-nonobese NIDDM and control subjects compared with both nonobese-nonobese NIDDM and control subjects. (all p's<0.05). Conclusion: NIDDM patients had more central and upper body adiposicity. Also both obese-obese and obese-nonobese NIDDM and control subjects had higher mean arterial pressures and central body obesity.

• 한국의류산업학회지
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• 제18권4호
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• pp.457-467
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• 2016

This study aimed to develop functional underwear for elderly women in their sixties in terms of good fit, wear comfort and body temperature regulation. To satisfy elderly women's physical and metabolical needs, an automatic temperature control system via PCM treatment was applied. Underwear pattern was produced by producing body surface replica, which was derived from 3D body parametric model. Differential ratios of outline length and area between 3D surface and 2D plane were 1.4% and 0.5%, respectively. The reduction rate was determined as 10% through the expert's evaluation. PCM treated fabric showed higher Q-max, meaning that it can facilitate the thermal transition in hot situation. Moreover, it also showed higher insulation to preserve heat and keep warm microclimate in a cold weather. Heat distribution measurements on various body parts revealed that the temperature after PCM treatment was significantly higher. The clothing pressure after 10% pattern reduction showed higher before reduction, at the same time, even lower than the comfort clothing pressure range of $5{\sim}10gf/cm^2$, implying that experimental garment of this research is acceptable in terms of clothing pressure. Evaluation results on the comfort to move in various motions proved that adequate clothing pressure improved the wear comfort in various motions.

• 재활복지공학회논문지
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• 제9권4호
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• pp.319-329
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• 2015

본 논문에서는 다자유도 동적 하네스 시스템 개발을 위해 일상동작에서와 트레드밀 보행 시 하네스 체중 지지에 따른 하지 동작 패턴에 관한 연구를 수행하였다. 건강한 성인 남성 5명을 대상으로 일상생활 동작과 하네스 체중지지에 따른 좌, 우 대퇴직근, 외측광근, 전경골근, 외측 비복근과 족압을 측정하였다. 실험 결과, 일상생활 동작 수행 시 EMG는 각 구분 동작들에 따른 특이적인 근육 활성을 나타내었다. 슬관절의 굴곡과 신전을 요하는 앉기, 서기, 계단 오르기, 계단 내리기 동작에서의 외측광근의 활성이 두드러졌다. 족압 분포의 경우 일상생활 동작 중 중력방향으로 내려오는 계단 내려오기 동작에서 가장 큰 족압 분포 값을 보였다. 수동형 하네스 체중 지지율이 증가에 따라 근육 활성도와 족압 분포 값은 감소하는 경향을 보였다. 이러한 결과를 토대로 체중지지를 통한 보행 훈련이 체중지지율 변화에 따라 다양한 환자 군에 적용 시킬 수 있을 것이다 판단된다.

• 한국전자통신학회논문지
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• 제8권11호
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• pp.1777-1784
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• 2013

본 연구는 필라테스 매트 운동을 통해 신체조성과 혈관탄성도의 변화를 확인하고 향후 노인 건강 증진을 위한 운동프로그램시 근거자료로 활용하고자 시도하였다. 노인 여성 30명을 대상으로 대조군과 운동군으로 분류하여 운동군은 1회 60분씩, 매주 3회 총 12주간 필라테스 매트 운동을 실시하였다. 신체조성에서는 골격근량(p<.01)과 체지방률(p<.01)이 통계적으로 유의한 감소가 있었고, 체지방량에서는 통계적으로 유의한 차이가 없었다. 혈관탄성도에서는 수축기 혈압(p<.01)과 말초 동맥압(p<.01)이 통계적으로 유의한 감소가 있었고, 이완기혈압과 대동맥압에서는 통계적으로 유의한 차이가 없었다.. 결론적으로 12주간 필라테스 매트 운동은 노인 여성의 신체조성과 혈관탄성도에 긍정적인 효과가 있음을 알 수 있었다.