http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
도시지역 초등학생 비만 수준 및 관련 요인에 대한 연구 -사회경제적 요인을 중심으로-
강희태,박경희,권영준,임형준,백도명,이현주,주영수,Kang, Hee-Tae,Park, Kyung-Hee,Kwon, Young-Jun,Im, Hyoung-June,Paek, Do-Myung,Lee, Hyun-Joo,Ju, Young-Su 대한예방의학회 2006 예방의학회지 Vol.39 No.5
Objectives: This study was conducted to investigate the prevalence of childhood obesity, the association between the undesirable lifestyles and socioeconomic factors, the association between childhood obesity and various risk factors, including socioeconomic factors, and the agreement between the body mass index (BMI) classification and the body fat percentage. Methods: The study subjects were all the 5th grade students from all the elementary schools in Gunpo City, Kyunggi Province, South Korea (4043 children at 22 schools). The subjects were measured for their height, weight and percent body fat etc. and they were also surveyed by questionnaire from March 18th to April 25th, 2005. To determine whether the children were within normal limits or not, standardized BMIs for each age group were used. The data was analyzed by logistic regression analysis using SAS 9.0 version. Results: The prevalence of childhood obesity prevalence was 25.1 %. Boys had a higher prevalence of obesity (27.5%) than did the girls (22.5%). Children had tendencies of having undesirable lifestyles and getting obese if they had a lower socioeconomic status. The risk factors for childhood obesity were low paternal education (OR: 1.17, 95% CI : 0.97-1.42) and non-parental caregivers (OR: 1.34, 95% CI : 0.98-1.82). Other risk factors for childhood obesity were a high birth-weight, longer TV/computer-using time, a lower fruit-eating frequency, short sleeping hours and parental obesity. The agreement rate between the BMI classification and the body fat percentage was 93.1 %. Conclusions: This study showed the children had a higher prevalence of obesity: further, not only individual lifestyles, but also socioeconomic factors could influence childhood obesity. Childhood obesity was especially more problematic for children with a low socioeconomic status.
노승훈(Seung-Hoon Ro),정평수(Pyeung-Soo Jeong),안재우(Jae-Woo An),강희태(Hee-Tae Kang),이태훈(Tae-Hoon Lee) 한국산업융합학회 2010 한국산업융합학회 논문집 Vol.13 No.4
Laser welding is widely used for precision welding because of superior mechanical properties and high productivity. Generally the accuracy of the welding is determined by the distribution of the bead which is affected by the structural vibrations of the equipment. This study was originated to stabilize a laser welding machine to minimize the bead distribution for the precise joining. The structural properties of the laser welding machine have been investigated to analyze the major factors of the vibrations to cause the bead distribution. The ideas for the design improvement have been applied to the simulation model to identify the effects and further to achieve the stability design and to minimize the bead distribution. The result shows that a few simple design alterations can substantially suppress the structural vibrations and improve the welding accuracy. The procedure used for this study can also be applied to similar welding equipments for improving the structural stability and the welding accuracy.
가공정도 향상을 위한 Milling Machine의 안정화 설계
노승훈(Seung-Hoon Ro),이민수(Min-Su Lee),박근우(Keun-Woo Park),강희태(Hee-Tae Kang),이종형(Jong-Hyung Lee),양성현(Seong-Hyeon Yang) 한국산업융합학회 2011 한국산업융합학회 논문집 Vol.14 No.2
Since the most exclusive machines of the modern industries which require the nano precision rates are evolved from the machine tools, the design of the stable machine tool structure is very critical. Exclusive machines for the modern industries such as semiconductor, solar cell and LED have surface machining processes which are similar to the face cutting and grinding of conventional machine tools. This study was initiated to stabilize a milling machine structure and further to help design those exclusive machines which have similar machining mechanisms. The vibrations inherent to the machine tool structures hurt the precision machining as well as damage the longevity of the structures. There have been numerous researches in order to suppress the vibrations of machine tool structures using the extra modules such as actuators and dampers. In this paper, the dynamic properties are analyzed to obtain the natural frequencies and mode shapes of a machine tool structure which reflect the main reasons of the biggest vibrations under the given operating conditions. And the feasibility of improving the stability of the structure without using any additional apparatus has been investigated with minor design changes. The result of the study shows that simple changes based on proper system identification can considerably improve the stability of the machine tool structure.