• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.2
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• pp.278-284
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• 2009

The global force and interaction body force density were evaluated in permanent magnets by using the virtual air-gap scheme incorporating the finite-element method. Until now, the virtual air-gap concept has been successfully applied to calculate a contact force and a body force density in soft magnetic materials. These force calculating methods have been called as generalized methods such as the generalized magnetic charge force density method, the generalized magnetizing current force density method, and the generalized Kelvin force density method. For permanent magnets, however, there have been few research works on a contact force and a force density field. Unlike the conventional force calculating methods resulting in surface force densities, the generalized methods are novel methods of evaluating body force density. These generalized methods yield the actual total force, but their distributions have an irregularity, which seems to be random distributions of body force density. Inside permanent magnets, however, a smooth pattern was obtained in the interaction body force density, which represents the interacting force field among magnetic materials. To evaluate the interaction body force density, the intrinsic force density should be withdrawn from the total force density. Several analysis models with permanent magnets were tested to verify the proposed methods evaluating the interaction body force density and the contact force, in which the permanent magnet contacts with a soft magnetic material.

• PNF and Movement
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• v.9 no.4
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• pp.23-31
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• 2011

Purpose : The aim of this study was to investigate the correlations between body compositions and bone mineral density in young women and postmenopausal women with low bone mineral density. Methods : Eleven young women (age, $25.85{\pm}1.96yrs$; height, $160.28{\pm}2.16cm$; weight, $56.89{\pm}9.66kg$) and ten postmenopausal women (age, $25.85{\pm}1.96yrs$; height, $160.28{\pm}2.16cm$; weight, $56.89{\pm}9.66kg$) with low bone density on femur neck were participated in this study. All subjects performed the measure of body composition and BMD on lumbar body and femur neck. Results : The results were as follows. Percent body fat, waist-hip ratio and body mass index(BMI) were significantly increased in postmenopausal women. BMD in lumbar body and femur neck were significantly decreased in postmenopausal women. There were negative strong correlation between BMD of the femur and age in young women. There were negative strong correlation between BMD of the femur and age or the years of menopause in postmenopausal women. There were positive strong correlation between BMD of the femur and BMD of lumbar body. Conclusion : Percent body fat and BMI were more increased in young women than in postmenopausal women. And there were negative strong correlation between BMD and age or the years of menopause in postmenopausal women.

• Journal of International Academy of Physical Therapy Research
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• v.3 no.1
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• pp.383-390
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• 2012

The aim of this study was to investigate the correlation among bone mineral density(BMD), body composition and body circumference on 20's college women in Hwaseong. A total of 86 subjects were measured with BMD and body composition and body circumference. To evaluate the correlation between BMD and body composition, bone density and body weight, body mass index(BMI), lean body mass, muscle mass, fat mass and body fat mass were compared. The results of this study, weight was considered the strong correlation with BMD than the height and BMI seems to be greater significance rather than the lumbar spine and femur BMD. In addition, the relationship between body composition and BMD, lean body mass, muscle mass, body fat mass were the most relevant factors and BMD. The relationship between BMD and body circumference that have been difficult because of not enough previous studies but somewhat the study showed that association.

• Journal of the Korean Ceramic Society
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• v.43 no.12 s.295
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• pp.859-864
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• 2006

For the pressure compaction process of the ceramic powder, the green density is very different with both the ceramic body shape and the processing conditions. The density difference cause non-uniform shrinkages and deformations, and make cracks in the sintered ceramics. In this paper, Material properties of the alumina powder mixed with binder and the friction coefficient between the powder and the tool set were determined through the simple compaction experiments: Also the powder flow characteristics were simulated and the green density was analyzed during the powder compaction process with Finite Element Method (FEM). The results show that the density distributions of the green body were improved at the optimized processing condition and both the possibility of the farming crack generation and rho deformation of the sintered Alumina body were reduced.

• Journal of Nutrition and Health
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• v.28 no.4
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• pp.282-290
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• 1995

Subcutaneous fat thickness of 74 young male was measured at six sites(biceps, triceps, subscapula, suprailiac, abdomen, thigh). The present study compared caliper with ultrasound measurements for the estimation of body fat. Caliper measurements subcutaneous at six sites had higher coefficient variation than did the ultrasound measures. Caliper measurements subcutaneous at six sites had higher ratio (caliper/ultrasound) than did the ultrasound measures. Compared to other body sites, the correlations between caliper and ultrasound measurements were high for the subscapula(r=0.7327), abdomen(r=0.7355) and thigh (r=0.7207) sites. the correlations between caliper and ultrasound measurements were high for the suprailiac(r=0.6616) site by lean group. the correlations between caliper and ultrasound measurements were high for the abdomen(r=0.7636) site by normal group. The correlations between caliper and ultrasound measurements were high for the subscapula (r=0.8959) and abdomen(r=0.8237) sites by obese group. Ultrasound measurement of biceps(r=-0.4459), abdomen9r=-0.4469), thigh(r=-0.4348) had the highest correlation with body density. Caliper measurement of triceps(r=-0.4017), subscapula(r=-0.4454), abdomen(r=-0.4293) had the highest correlation with body density. Ultasound measurements subcutaneous fat at lean group, obese group had higher coefficients of correlation with body density than did the caliper measurement. Caliper measurements subcutaneous fat at normal group had higher coefficients of correlation with body density than did the ultrasound measures. Ultrasound showed to be superior to the caliper technique in measuring subcutaneous fat of obese persons.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.53 no.8
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• pp.461-465
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• 2004

This paper analysed the induced current density by electric field of human body under the 765 kV transmission line considering permittivity and conductivity. As permittivity of human body is very high as $10^6$ at 60 Hz, special numerical computation technique in Surface Charge Method(SCM) for composite media with extremely different properties is applied to reduce calculation error of induced current density and electric field inside the human body. Calculation results show that the average of the induced current density inside human body is about 3mA/$m^2$, which is less than ICNIRP criterion (10mA/$m^2$).

• The Korean Journal of Physiology
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• v.2 no.1
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• pp.31-38
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• 1968

Total body fat measurement by means of skinfold thickness was performed in 94 secondary school boys. Hydrostatic weighing was made on the same subject and corrected for residual volume in lung. Skinfold thicknesses at four sites, namely, back, waist, arm and abdomen, were compared with total body fat calculated from the equation given by Keys and Brozek and regression equation were computated. In 48 middle school boys aged between 13 and 16 years and 46 high school boys aged between 16 and 19 years, skinfold thicknesses increased at all 4 sites as age increased. The body density, however, showed different pattern. In middle school ages, body density showed little variation. Density in 13-14 years was 1.0608, in 14-15 years 1.0578 and in 15-16 years 1.0546. In high school ages density in-creased abruptly to 1.0703 (16 yr.), 1.0730 (17 yr.) and 1.0740 (18 yr.). Subsequently 15 years was a boundary for density change and total body fat change. In middle school boys as a group of 48 the observed values were: density: 1.0562, total body fat: 15.9%, mean skinfold thickness at four sites: 6.02 mm. The coefficient of correlation between mean skinfold thickness and density were r=-0.759 and r=0.781 with %fat. The regression equations were : Body $density=-0.00527{\times}Mean$ skinfold thickness (mm)+1.0879, %Fat=$1.933{\times}Mean$ skinfold thickness (mm)+4.26 In high school boys the values were: density: 1.0723, body fat: 10.4%, and mean skinfold thickness: 7.89 mm. Coefficients of correlation between mean skinfold thickness and density were r=-0.868 and r=0.855 with % fat. Thus, Body density=$-0.00365{\times}Mean$ skinfold thickness (mm)+1.1008, and %Fat=$1.326{\times}Mean$ skinfold thickness (mm)-0.064, were obtained. Although skinfold thicknesses at 4 sites showed a continuous increase in absolute value as age increased, relative growth of skinfold at specific site differed. On arm the growth of skinfold showed a decrease and on waist it showed an increase as compared to the mean thickness.

• The Journal of Korean Physical Therapy
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• v.15 no.4
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• pp.466-478
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• 2003

This study was to evaluate the body composition and bone mineral density according to aging in adult and investigated the relationship between various parameters such as body mass index(BMI), bone mineral density(BMD), bone mineral content(BMC), lean body mass(LBM), fat mass(FM) and the value obtained from dual energy X-ray absorptiometry(DEXA). The subjects were composed of healthy adult male and female who were $20^{\sim}73$ years old and they were divided three group according to age (A group : 20-39 yrs., B group : 40-59 yrs., C group : more than 60 yrs.). The conclusion derived from statistical analysis was as follows : 1. Bone mineral content and density were significantly affected by lean body mass(relatively, R=0.85 - 0.63). 2. There was significant difference among age groups in total bone mineral density. 3. There was significant difference among age groups in bone mineral content of male and female. 4. Lean body mass is diminished according to age, but there was not significant difference among age groups. 5. Fat mass of A group in male had the highest mass and followed by C group and B group. In female groups, fat mass of A group had the highest mass and followed by B group and C group. Abdominal fat mass is increased according to age. This result suggest that aging was closely relation with loss of muscle mass, bone mineral density and bone mineral content.

• Journal of Internet Computing and Services
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• v.9 no.3
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• pp.91-101
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• 2008

This paper proposes component-based density propagation for tracking a component-based human body model that comprises components and their flexible links. We divide a human body into six body parts as components - head, body, left arm, right arm, left foot, and right foot - that are most necessary in tracking its movement. Instead of tracking a whole body's silhouette, using component-based density propagation, the proposed method individually tracks each component of various parts of human body through a human body model connecting the components. The proposed human body tracking system has been applied to track movements usee for young children's movement education: balancing, hopping, jumping, walking, turning, bending, and stretching. This proposed system demonstrated the validity and effectiveness of movement tracking by independently detecting each component in the human body model and by acquiring an average 97% of high tracking rate.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.8
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• pp.1952-1966
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• 1994

The body segment parameters of twelve young male Korean were measured to compare with the results of foreign cadaver studies. A human body was assumed to have fourteen body segments. The mass of each segment was measured with a water immersion test and the mass center of a segment was determined on the balance platform by changing postures. In the case of Korean, because of the difference in body proportion, the mass center of whole-body is located further from the distal end of head(Korean : 44.9% vs. Caucasian : 41.2%), and the mass center of each segment also located in different proportional locations. The existing regression equations, which can estimate segment mass based upon the anthropometric dimensions, estimates segment mass (the mass of shank) for Korean with 13% error. Therefore, it is not recommended to estimate the mass, and the moment of inertia of body segment of Korean based on the existing equations. However, the density information of body constituents was similar enough to apply it to Korean density. It was validated by the comparison between the results of the direct immersion method and 3-dimensional volume reconstruction of segment form the cross sectional images of CT-scan. The average body density measured form twelve subjects was $1.035{\;}kg/m^3$ and showed deceasing trendency.