• 산업기술연구
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• 제31권A호
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• pp.33-38
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• 2011

In an express tilting train, side wall insulating the noise from the exterior sound source consists of two parts. One is the layered composite panel including aluminum honeycomb, glass wool and nomex honeycomb. The other is the double glazed window. In this study, sound insulation performance of the two parts is investigated by mass law and experiment. Based on ASTM E2249-02, the intensity sound transmission loss (TL) is measured on the specimens of the two parts. Mass law deviation (MLD) is considered in order to compare the sound insulation performance in respect of weight. Contribution of each part to the sound insulation is analyzed and the sound insulation strategy for the interior noise reduction is investigated.

• Journal of Astronomy and Space Sciences
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• 제23권3호
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• pp.189-198
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• 2006

BVRI CCD 측광 관측에 의하여 질량비가 작은 접촉쌍성 HN UMa와 II UMa의 새로운 광도곡선을 얻었다. 새로운 광도곡선과 이미 발표된 분광관측으로부터 Wilson-Devinney 프로그램을 이용하여 이 두 별의 궤도요소와 절대 물리량을 얻었다. HN UMa와 II UMa를 포함한 절대물리량이 잘 알려진 21개의 질량비가 작은 접촉쌍성들의 진화 상태를 조사하였다. 그 결과 질랑비가 작은 접촉쌍성의 반성은 영년주계열 아래 놓이며, 이러한 현상은 질량이 작은 접촉쌍성의 반성에서의 질량손실을 가정할 경우, 비록 작의 양의 질량이지만 반성에서의 질량 감소는 상대적으로 광도의 감소가 현저히 작아지기 때문일 것으로 예상된다.

• 대한물리의학회지
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• 제19권1호
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• pp.31-41
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• 2024

PURPOSE: This study examined the distribution dynamics and proposed determinants, including morphological measurements, clinical laboratory tests, and lifestyle factors among young Korean men aged 20 to 29 years with the coexistence of age-related loss of skeletal muscle mass and obesity (CALSMO). METHODS: Six hundred and sixty-six participants were divided into two groups based on their skeletal muscle mass index, with 12 individuals categorized in the CALSMO group and the remaining 654 in the normal group. The proposed determinants variables consisted of three main components: morphological measurements, clinical laboratory tests, and lifestyle factors. The morphological measurement variables were height, weight, body mass index, waist circumference, and skeletal muscle mass index. The clinical laboratory tests were fasting glucose, triglyceride, total cholesterol levels, and systolic and diastolic blood pressure. The lifestyle factors considered were alcohol consumption and tobacco use. Complex sampling analysis was performed for the evaluation. RESULTS: The distribution dynamics were determined to be 1.81(1.02-3.18) %. Morphological factors, such as height, weight, body mass index, waist circumference, and skeletal muscle mass index, showed significant differences (p < .05). The clinical laboratory test variables, specifically the fasting glucose, triglyceride, and total cholesterol levels, also exhibited significant differences (p < .05). The lifestyle factor, alcohol consumption, also showed a significance (p < .05). CONCLUSION: This study provides insights into the distribution dynamics. The proposed determinants in young Korean individuals with CALSMO are height, weight, body mass index, waist circumference, skeletal muscle mass index, fasting glucose, triglyceride, total cholesterol levels, and alcohol consumption.

• 한국토양비료학회지
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• 제35권6호
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• pp.361-371
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• 2002

밭농사에 다원적기능중의 하나로 알려져 있는 토양유실저감기능에 대하여 기존에 보고된 결과를 수정 보완하였으며, 그 얻은 결과를 요약하면 다음과 같다. 1. 우리나라 밭농사의 토양유실량을 USLE모형을 이용하여 계산하였으며, 각 인자별 값은 다음과 같다. 강우인자(R)값은 429.4, 토양침식성인자(K)값은 0.15, 지형인자(LS)값은 1.72, 작물인자(C)값은 0.275, 토양관리인자(P)값은 0.856이었다. 2. USLE모형에 의한 우리나라 밭농사의 토양유실량은 ha당 연간 26.1톤이었으나, 나지토양의 경우에는 ha당 연간 110.8톤으로서 밭농사에 의한 토양유실량은 나지에 비하여 23% 수준이었으며, 연간 밭농사는 나지토양에 비하여 84.7톤의 토양유실량 저감기능이 있었다. 이것을 밭면적전체로는 연간 62,650천톤에 해당되었다. 3. 밭농사에 의한 토양유실저감량을 객토단가로 환산할 경우 연간 4,974억원에 해당하였다. 4. 토양유실 세부모형중 LS값이 1.72로 매우 높았는데, 밭농사의 공익기능을 제고하기 위해서는 등고선, 대상재배 등 농경적인 접근과 계단전 등의 전환 등 농토목적인 접근방식이 필요하다고 생각된다.

• 정보저장시스템학회논문집
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• 제6권2호
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• pp.57-62
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• 2010

This paper measured and analyzed the source of total power loss of an ODD of a notebook computer. It shows that the biggest power loss is the windage loss due to the friction between rotating disk and surrounding air. It measured the power loss by the tilting motion of a rotating disc which is originated from the unbalanced mass of the rotating disc or the squareness between case-rotor and shaft. The power loss of rotating disc due to tilting motion was also calculated by using FLUENT, and it was correlated with the measured one. This paper shows that the one of the effective methods to reduce the power loss of an ODD is to reduce the tilting motion of a rotating disc.

• 천문학회지
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• 제38권2호
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• pp.161-164
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• 2005

We present a theoretical formalism by which the global and the local mass functions of dark matter substructures (dark subhalos) can be analytically estimated. The global subhalo mass function is defined to give the total number density of dark subhalos in the universe as a function of mass, while the local subhalo mass function counts only those sub halos included in one individual host halo. We develop our formalism by modifying the Press-Schechter theory to incorporate the followings: (i) the internal structure of dark halos; (ii) the correlations between the halos and the subhalos; (iii) the subhalo mass-loss effect driven by the tidal forces. We find that the resulting (cumulative) subhalo mass function is close to a power law with the slope of ${\~}$ -1, that the subhalos contribute approximately $10\%$ of the total mass, and that the tidal stripping effect changes the subhalo mass function self-similarly, all consistent with recent numerical detections.

• Nutritional Sciences
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• 제5권4호
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• pp.221-227
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• 2002

The objective of this study was to examine the effects of a weight loss program on the degree of obesity and levels of resting energy expenditure (REE) in overweight subjects according to their mitochondrial uncoupling protein 2 (UCP 2) genotype. Twenty-three subjects with a body mass index (BMI) greater than 27 were recruited from the Obesity Clinic of the Kyung-Hee University Hospital during the period of December 2000 - August 2001. The subjects were genotyped for the exon 8 allele; 15 subjects were found to be of del/del genotype, 8 were del/ins, and none were of ins/ins genotype. No significant association was found between the different UCP 2 genotypes and the initial levels of weight, fat mass (FM), lean body mess (LBM), BMI, REE, and REE/LBM ratio. After 12 weeks of a weight loss program, body weight and FM were significantly decreased, while LBM, total body water (TBW), and REE were not changed, irrespective of UCP 2 genotype. Initial fasting plasma levels of albumin, glucose, triglyceride, lipoprotein cholesterol, insulin, free triiodo-thyronine (T3), free fatty acid (FFA), and leptin were not different according to the UCP 2 genotype; furthermore, these blood parameters were not changed after the 12-week weight loss program. However, plasma levels of leptin decreased in both the del/del and ins/del genotypes, from 18.7 ng/ml to 13.4 ng/ml (p<.05), and from 18.1 ng/ml to 13.9 ng/ml (p＜.05), respectively, after the weight loss program. In conclusion, this study found no significant association between the del/del or del/ins UCP 2 genotypes and differing levels of REE or differing degrees of obesity, either before or after a weight loss program. This study provided evidence that a well- managed weight loss program could maintain levels of REE, which plays an important role in the maintenance of energy balance.

• 가정의학회지
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• 제39권6호
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• pp.355-359
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• 2018

Background: Body image is associated with the perception of people on themselves. Influencing factors are generated internally and/or externally. The most common issue pertaining to body image is body weight and weight loss. This study aimed to determine the association between body weight perception and weight loss practices among college students. Methods: A cross-sectional study was conducted involving 297 college students from private nursing colleges in the state of Kelantan, Malaysia. A self-administered questionnaire was used to assess sociodemographic characteristics, body weight perception, and weight loss methods. Weight and height were measured, and body mass index (BMI) was calculated based on weight and height measurement. The World Health Organization BMI cutoffs were applied in the study. Results: More than half (54.2%) of college students perceived their weight correctly as per actual measured BMI. A total of 51.5% of participants had tried various methods to reduce their weight. Body weight perception is associated with weight loss practices (odds ratio, 0.31; 95% confidence interval, 0.19-0.50; P<0.001) adjusted for sex, marital status, and status of having obese family members. Those who had correct body weight perception were less likely to engage in weight loss practice. Food intake restriction (42.4%) is the most popular weight reduction method among students in nursing colleges. Over a quarter of the participants chose physical exercise (25.3%) to reduce their weight, and a small number engaged in unhealthy weight loss practices. Conclusion: Body weight perception is an important factor that influences the practice to reduce weight especially among young adult group and college students.

• 한방비만학회지
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• 제21권1호
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• pp.22-31
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• 2021

Objectives: We conducted a retrospective chart review to investigate the effects of Korean Medicine (KM) treatment on weight loss in patients with morbid obesity (body mass index [BMI]≥30 kg/m²) and to compare the effects of KM counseling and non-counseling on weight loss. Methods: We performed a retrospective chart review of patients with morbid obesity who received KM treatment for at least 1 month. We evaluated the effects of KM treatment on body weight, BMI, body fat, fat mass, EuroQol-5D, and the Korean version of the obesity-related quality of life scale (KOQOL). We also assessed the liver and kidney functions, and adverse events. We performed a comparative analysis between the counseling and non-counseling groups. Results: A total of 37 patients who underwent 4 weeks of KM treatment involving Wolbi-tang, electroacupuncture, and KM counseling were included in this study. Twenty-one patients were assigned to the counseling group and sixteen patients to the non-counseling group. There was a significant decrease in weight, BMI, fat mass, and KOQOL (P<0.05) with improvements in total cholesterol, low-density lipoprotein, and triglycerides. The counseling group had a greater reduction in body weight, BMI, body fat, and fat mass compared to the non-counseling group, although it was not significant. In the BMI below 35 (n=25), the reduction ratio of body weight, body fat mass, and body fat was higher in the counseling group than in the non-counseling group; additionally, body fat decreased significantly in counseling group (P<0.05). No severe adverse effects were observed. Conclusion: KM treatment could be effective for weight loss, especially in patients with morbid obesity, KM counseling could also be a good tool for weight loss, typically in patients with BMI<35 kg/m².

• 대한기계학회논문집B
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• 제26권1호
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• pp.150-158
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• 2002

Local heat/mass transfer and friction loss in a square duct roughened with various types of continuous and discrete rib turbulators are investigated. The combined effects of the gap flows of the discrete ribs and the secondary flows are examined for the purpose of the reduction of thermally weak regions and the promotion of the uniformity of heat/mass transfer distributions as well as the ;augmentation of average heat/mass transfer. The rib-to-rib pitch to the rib height ratio (p/e) of 8 and the rib angles of 90° and 60° are selected with e/D$\_$h/=0.08. The vortical structure of the secondary flows induced by the parallel angled arrays are quite distinct from that induced by the cross angled arrays. This distinction influences on heat/mass transfer and friction loss in all the tested cases. The gap flows of the discrete ribs reduce the strength of the secondary flows but promote local turbulence and flow mixing. Consequently, the angled discrete ribs with the small gaps provide a more uniform heat/mass transfer distribution sustaining high average heat/mass transfer.