ISO-5167-5에 따른 콘 미터(Cone meter) 유출 계수의 타당성 조사

유요한(Yo han YOU),박주영(Joo young PARK),차기철(Ki chul Cha) 대한기계학회 2019 대한기계학회 춘추학술대회 Vol.2019 No.11

레이놀즈 수에 따른 노즐 유량계의 유출계수 특성

유요한(Yu Han You),박주영(Joo Young Park),차기철(Ki Chul Cha),홍경환(Kyoung Hwan Hong),박민기(Min Gi Park),박준수(Jun Su Park) 대한기계학회 2019 대한기계학회 춘추학술대회 Vol.2019 No.4

부위별 생체 전기 임피던스와 피부두겹집기 측정을 이용한 비만아동과 정상아동의 체성분 비교

김명기(Myung Gi Kim),김성수(Sung Soo Kim),김차용(Cha Yong Kim),차기철(Ki Chul Cha),정일규(Jeong Ill Gyu) 한국사회체육학회 1998 한국사회체육학회지 Vol.9 No.-

This study was designed to study the relationship between the composition(FFM, %fat) variables obtained from segmental bioelectrical impedance measurement and skinfold thickness measurement and also to compare the characteristics of body composition between the obese and normal children. The subjects of this study consisted of 44 obese children(boys: 23, girls: 21)s and 67 normal children(boys: 35, girls: 32) who were ranged from 7 to 13 years old. The results induced from the measurements and data analysis follows as 1. The electrical resistance of arm segment was the largest showed highest value among the all body segments, and followed by leg region and trunk region in both groups. The obese children had children had lower electrical resistance value than the normal. 2. The value of FFM obtained skinfold measurement(Slaughter, 1988) showed the highest correlation with the Ht^2/R_RA Ht^2/R_T, Ht^2/RP_RL measured by SBIA and %fat could be represented very well by the sum of skinfold thickness of the triceps and scapular segments. The difference of electrical impedance values between each body segment means that the FFM of body segment was differently each other. Besides the multiple regression equation that each subjects`s height was used as the length of a conductor can provide the most validity in predicting the FFM of children and also the weight was a important for the prediction of FFM. Finally, as the standard variable of FFM, the more reliable can be obtained by the method such as DEXA or underweighing measurement in predicting FFM of children.

20대 남 녀 신체구성 평가의 정확성 및 활용성을 높이기 위한 분석

김기진,차기철 한국운동과학회 1996 운동과학 Vol.5 No.2

20대 남·녀 신체구성 평가의 정확성 및 활용성을 높이기 위한 분석. 운동과학, 제5권 제2호. 227-246. 신체구성 평가의 정확서 및 활용성을 높이기 위한 분석결과는 다음과 같이 요약된다. 수중체중 측정법에서 잔기량의 3회 반복 직접측정법에 의한 결과중 최고치의 적용이 적절한 것으로 간주되며, 잔기량의 측정밥법은 폐활량 추정치의 적용 가능성이 재확인되었다. 신체밀도를 근거로 체지방률의 산출공식과 피하지방두께를 토대로 한 신체밀도 산출공식의 적용시 그 대상자의 특성이 중요하게 고려되어야 한다. 신체의 12부위 피하지방 두께중 일반 남자의 경우 삼두근 및 상장골 부위, 여자의 경우 겨드랑이 및 장단지 부위, 선수군의 경우 가슴부위 등이 신체밀도 산출에 가장 큰 영향을 미치는 것으로 나타났다. 체격요인 중에는 일반 남자의 경우 요위 및 요폭, 일반 여자의 경우 흉위, 대퇴골폭 및 둔폭, 선수군의 경우 요위 및 요폭 등이 신체밀도에 중요한 영향을 미치는 것으로 나타났다. 신체밀도는 배근력 및 유연성과 유의한(P<0.05) 상관관계를 나타냈으며, 근력의 악력 및 배근력, 유연성의 앉아 윗몸 앞으로 굽히기 중 배근력이 가장 높은 상관계수를 나타냈다. Analysis of applicapability and reliability on the measurement of body composition in 20-aged women and men. Exercise Science, 5(2): 227-246. The highest values of results of repeated measurement in the underwater weight and residual volume showed the appropriate values for the body composition assessment. In the measurement of residual volume, applicability of Predicted values from vital capacity was reconfirmed as compared to 3-repeated respiration method of oxygen gas. In the prediction of %fat from body density and the application of body density assess equation from skinfolds, the consideration of subjects character was asked for the presentation of optimal equation. In the relationship between body density and skinfolds, the most important factors of male subjects showed skinfolds of brachial triceps and suprailiac parts, female subjects showed skinfolds of axillary and calf parts, and athletes showed skinfold of thoracic part. In the relationship between body density and physique factors, the most important factors of male subjects showed the width and circumference of waist, female subjects showed the breast circumference and the width of thigh and hip. Body density showed the differences as the somatotypes, and correlated to the lower back strength and the flexibility.

새로운 생체 전기 임피던스법

김기진,최승훈,차기철,손정민 대한비만학회 1997 The Korean journal of obesity Vol.6 No.1

A new bioelectrical impedance method has been developed a)d evaluated. The electrodes were made of stainless steel and electrical interfaces were created by an upright subject gripping hand elecovdes and stepping onto foot eiectrodes, Eight tactile electrodes were in contact with surfaces of both hands and feet; thumb, palm and fingers, front sole, and rear sole. Automatic on-off swit. Ches were used to change current pathways and to measure voltage differences for target segments. Segmental bady resistaoces and wh.ole body resistance(R_(WHOLE),) were measured in 60 healthy subjects. Segmental resistances of right arm(R_(RA)), left arm(R_(LA)), trunk(R_T), right leg(R_(RL)) and left leg(R_(LL)) were 310.0±61.6 Ω, 316.9±64.6 Ω, 25.1±3.4 Ω, 236.8±31.2 Ω and 237.6±30.4 Ω, respective1y. Lndividual segmental impedance indexes(Ht2/RRA, Ht2/RT, and Ht2/RLA) were closely related to lean bodv mass(1.BM) as measured by densitometry ranged from r= 0.925 to 0.960. Ht₂(R_(RA)+R_T+R_(RA)) predicted LBM slightly better(r=0.969) than the traditivnal index, Ht₂/R_(WHOLE)(r=0.964), supporting the accuracy of the segmental rneasurement. A multiple regression equation utilizing Ht₂/R_(RA), Ht₂/R_T and Ht₂/R_(RL) predicted LBM with r=0.971. Ht₂/R_(RA) term of the regression contributed to more than 40% of the LBM prediction, indicating that lean mass of an represented whole bodv LBM mare closely than other body segments. The new electrode method was characterized by upright posture, eight tactile electrodes, segmental measurements and utilization of electronic switches in comparison with the conventional method, The measurement with this new method was extremely reproducible, quick and easy to use.

체성분분석기 InBody 3.0으로 측정된 허리둘레 및 허리-엉덩이 둘레비의 정확도

정영진,박지영,차기철,박혜순 대한비만학회 2002 The Korean journal of obesity Vol.11 No.2

연구배경 : 비만의 평가에 있어 지방 분포를 파악하기 위하여 허리둘레의 측정이 강조되고 있다. 체성분분석기 InBody 3.0에서는 허리 및 엉덩이 둘레를 자동으로 측정하여 결과를 제시하고 있으며 간편함을 이유로 그 결과가 많이 이용되고 있다. 이에 체성분분석기 InBody 3.0에 의해 측정된 허리 둘레, 엉덩이 둘레 및 허리- 엉덩이 둘레비 (WHR) 의 정확성에 대해 알아보고자 본 연구를 시행하였다. 방법 : 일개 종합병원 비만클리닉을 방문하여 체성분분석기 InBody 3.0을 사용한 345명을 대상으로 훈련된 1명의 측정자에 의하여 허리둘레 (늑골 하단과 장골능의 중간부위 : 배꼽 부위 : 장골능 상부) 및 엉덩이둘레 (엉덩이의 가장 튀어나온 부위)를 줄자로 측정하였다. 체성분분석기 InBody 3.0에 의해 자동 계측된 값들과 수동 측정된 허리둘레, 엉덩이 둘레 및 WHR 에 대해 비교하였다. 결과 : InBody 3.0에 의해 자동 계측된 허리둘레는 각각의 측정 부위에서 수동 측정된 수치들보다 각각 평균 7.81±5.72cm, 4.20±6.51 cm, 4.68±5.99 cm 유의하게 더 큰 것으로, 허리- 엉덩이 둘레비 (WHR) 의 경우에도 각각 0.067±0.060 , 0.031±0.063, 0.036±0.060로 더 높은 값을 보였으며, 이러한 차이는 체질량지수가 높을수록 더 크게 나타났다 (p<0.05). 수동 측정된 허리둘레 및 WHR에 의한 복부비만을 참값으로 하여 자동 계측의 정확도를 살펴보았을 때 부위별 위양성률이 7 ~ 17%로 나타났다. 결론 : 체성분분석기 InBody 3.0에서 계측된 허리 둘레 및 WHR은 자동으로 측정된다는 간편함이 있지만 실제치보다 과대 평가하는 경향을 보였다. 지방 분포 및 복부비만의 평가를 위해서는 줄자를 이용하여 정확하게 측정하는 것이 중요하다. Background : Assessment of waist circumference is being emphasized for the evaluation of fat distribution. InBody 3.0, a body composition analyzer device, automatically measures waist circumference, hip circumference, and waist-hip ration (WHR), thus its results are widely utilized due to its convenience. The purpose of this study was to assess the accuracy of the waist circumference, hip circumference, and WHR measurements obtained through InBody 3.0. Method : The participants involved 345 patients who visited the obesity clinic in a hospital and had been evaluated by InBody 3.0. Waist circumference (midpoint between the lower border of the rib cage and the iliac crest; umbilical level; top of the iliac crest) and hip circumference ( the widest area of the buttock) were measured manually by a single trained personnel. The waist, hip circumferences, and WHR obtained by InBody 3.0 were compared with the waist, hip circumferences, and WHR obtained by manual unelastic tape measurement. Results : The waist circumference obtained by InBody 3.0 was significantly greater than the manually measured values at three different levels by 7.81±5.72 cm, 4.20±6.51 cm, 4.68±5.99 cm; waist to hip ration was also shown to be greater by 0.067±0.060, 0.031±0.063, 0.036±0.060 at each levels of waist measurement and this difference increased in proportion to BMI of the subjects (p<0.05). The false positive rate for assessment of abdominal obesity by the In Body 3.0 was 7 ~ 17% presuming that the abdominal obesity according to manual measurement of waist circumference and WHR were golden standards. Conclusion : Despite the convenience of the automatic measurement of waist circumference and WHR obtained by InBody 3.0, it had a tendency to overestimate the values. The importance of manual tape measurement in order to accurately evaluate fat distribution and abdominal obesity must be emphasized.

생체 임피던스 측정 방법을 한국인의 연령층별 체성분 분석에 관한 연구

손정민,김정희,신선영,차기철 대한영양사협회 2001 대한영양사협회 학술지 Vol.7 No.2

This study examined the age-related patterns in body composition cross-sectionally using Segmental bioelectrical impedance analysis(SBIA), specifically its two components, lean body mass(LBM) and body fat mass, in 1,452 men and 1,436 women with an age range of 19 to over 70 years. Mean height of male subjects was 174.1cm at peak in early 20's and was decreased continuously 0.2~0.3cm every year. Mean weight was greatest between late 20's and 40's, and was decreased quickly in 70's. Body fat mass was increased steadily before 30's and remained thereafter. Because decreasing lean body mass(LBM), percentage of body fat(PBF) increased continuously with aging. Mean height of female subjects was 161.7cm at peak in 20's and was decreased steadily around 0.2cm every year and thus an individual's height was decreased approximately 10cm in their life cycle. Body weight was increased steadily until 50's and then was decreased. Body fat mass was increased continuously and LBM remained constant and thus PBF was increased steadily with aging. SBIA can be used to compare body composition between genders and between ages. In future studies, SBIA could be applied widely to evaluate variations of body composition in subjects with different nutritional problems.

장기간 수영운동이 아동의 신체 각 부위별 제지방에 미치는 영향 : 부위별 생체 전기 임피던스법과 피부두겹집기법의 비교 a Comparison of Segmental Bioelectrical Impedance Analysis and Skinfold Thickness

김성수,김명기,이재현,김창국,김동재,차기철 대한스포츠의학회 1998 대한스포츠의학회지 Vol.16 No.2

The purpose of this study was to investigate the effect of long-term aerobic swimming exercise of fat free mass(FFM) on body segments and balance development of either right and left on body of children aged 8-13. Using anthropometric measurements, a segmental cross-sectional area of FFM was calculated impedance index(Height^2/Resistance segment) were used for these calculation. The exercise group were 48(25 boys, 23 girls) and the control group were 114(61 boys, 53 girls). The result follows as : Frist, The exercise group showed lower % body fat and higher FFM than control group. Second, In relation to the electrical resistance value of each body part measured by SBIA, exercise group revealed the simlar values on both arms and legs, while control group appeared lower right arm's electrical resistance value than left arm's. Third, The electrical resistance values from SBIA for each segments of body were differently showed, which meant that the distribution of FFM varied. In conclusion, long tern aerobic exercise such as swimming influenced the balance development of either right and left on body and electrical resistance values for each segments of body diverse, which showed that the distribution of FFM variously ranged by means parts of body.