• Transactions of the Korean Society of Automotive Engineers
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• v.5 no.3
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• pp.182-190
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• 1997

Recently to develope an automobile with better properties, much researches and investments are executed in many countries. In this paper, it is intended to minimize the weight of an engine block without changing the dynamic characteristics. The weight minimization is executed by the sensitivity of the natural frequency of the engine block. To decrease the engine weight, much less thickness than the original thickness of the engine is selected to initial value and the structure modification is performed to recover the dynamic characteristics of the engine. Here, the original thickness of the engine is 8mm and the initial thickness is selected to 5mm, 6mm and the number if the natural frequencies fitted are 2, 6, 7, respectively. As the results, it is found that; (1) the weight of each case could be reduced without changing the objective natural frequencies. Specially, in the case of fitting 2 natural frequencies with 5mm initial thickness the weight could be reduced to 4.21kg(23.3% for engine weight). (2) according to the driving frequency range of engine, the weight minimization could be performed choicely, (3) improving a vibration characteristics of a orignal structure, the weight minimization could be performed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.2
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• pp.89-94
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• 2001

Sword bean belongs to the subgenus Canavalia in the genus Canavalia. White and reddish varieties in sword bean were tested to obtain the basic information for improving the yield, quality, and cultural environments through the quantitative growth analysis. Growing plants were sampled at intervals of 10 days from 20 days after sowing. Whole plant weight increased during the period of 11-20 days after sowing in both varieties. The weight of each organ between two varieties increased similarly except leaf area. Whole plant weight changed more close to pod weight than any other characters. The leaf areas of both varieties increased from 50 days after sowing, var. white displayed S type curved line but var. reddish displayed slow S type curved line. The SGR of whole plant weight in both varieties had 3 maxima and 2 minima, 3 maxima and first minimum were shown at the same period but the second minimum was shown at different period. Both varieties showed bimodal curved line. All SGR of each organ and leaf area were shown the 2 maxima and 1 minimum in both varieties. The changes of SLA and LAR were not remarkable between two varieties but these were united together with the maximum of whole plant weight and root weight. ULWR and ULWR were shown similar in both varieties. Reddish variety was more prosperous in early growth stage than white variety because SLA, LAR and LWR were high. In surplus weight, both varieties increased rapidly during the period of 111-120 days after sowing that was applicable to the maximum SGR of pod weight. Surplus weight of var. white increased markedly during the same period comparing those of var. reddish.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.12
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• pp.1543-1551
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• 2010

A major aim of cattle genome research is to identify candidate genes associated with meat quantity and quality through QTL analysis for application in the livestock industry. Therefore, this study focused on discovery of useful SNPs within the LOC534614 gene, containing 12273_165 SNP which is located on the same site as the QTL on chromosome 6, and evaluation of the association between SNP and body weight and cold carcass weight in Hanwoo (Korean cattle) As a result of a BLAST search of the NCBI web site, we discovered that the mRNA sequence of the LOC534614 gene was similar to that of the coiled-coil domain containing 158 (CCDC158) for dog and human. According to the direct DNA sequence from the CCDC158 gene, we identified 19 polymorphic SNPs within exons and their flanking regions. Among them, 17 polymorphic SNPs were selected for genotyping in Hanwoo (n = 476) and seventeen marker haplotypes containing 12273_165 SNP (frequency >0.1) were identified. As a result of the association between 17 polymorphic SNPs and Hanwoo (n = 476), g.8778G>A SNP in exon 6 was found to be a non-synonymous SNP, and was significantly associated with body weight and cold carcass weight (p<0.05). We discovered 19 polymorphic SNPs in the CCDC158 gene on the QTL region of BTA 6 in Hanwoo and identified that the g.8778G>A SNP was significantly associated with body weight and cold carcass weight (p<0.05), which causes an amino acid variation from valine to methionine. Furthermore, statistical analysis demonstrated that the CCDC158 gene is strongly associated with body weight and cold carcass weight in Hanwoo. In this regard, the g.8778G>A SNP in the CCDC158 gene can be useful as a positional candidate for body weight and cold carcass weight for marker-assisted selection in Hanwoo.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.26 no.5
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• pp.47-56
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• 2023

The Quercus variabilis and Quercus dentata, which are said to be relatively drought tolerant among the important genus Quercus that represent deciduous broad-leaved forests in Korea. These two species are widely distributed worldwide in Korea, Japan and China (northern, central, western and eastern subtropical regions). This study compared the ecological niche breadth and overlap according to growth response in 4 soil moisture gradients for the two species and tried to reveal degree of competition and ecological niche characteristics. The ecological niche breadth was 0.977±0.020 for Q. variabilis and 0.979±0.014 for Q. dentata, the latter being slightly wider. And they were similar in 5 traits (stem length, leaf lamina length, leaf width length, stem weight, leaf petiole weight), Q. variabilis was more dominant in 4 traits (leaves number, stem diameter, leaf area, leaf petiole length), and Q. dentata was more dominant in 7 traits (root length, shoot length, plant weight, root weight, shoot weight, leaf weight, leaf petiole weight). The ecological niche overlap for soil moisture between the two species overlapped most in plant structure-related traits and least in photosynthetic organ-related traits such as petiole length. As a result of principal component analysis, degree of competition between the two species for soil moisture was more severe when the soil moisture condition was low than high. Among the measured traits that affect the two-dimensional distribution, 8 traits (Leaves number, Shoot length, Stem length, Plant weight, Root weight, Shoot weight, Stem weight, Leaves weight) were correlated with the factor 1, and 2 traits (Leaf width length, Leaf petiole weight) were correlated with the factor 2 (r>0.5). These results show that the ecological response of the two species to soil moisture is not a few traits involved, but several traits are involved simultaneously.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.5
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• pp.640-647
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• 2008

Breed differences in adult animals are determined during fetal development. If interventions are to be developed that influence growth of muscle and fat, it is important to know at which time during gestation breed differences appear and are fixed. The objective of this study was to characterize fetal development in cattle of different breeds. Pregnant cows of 4 cattle breeds with different growth impetus and muscularity were slaughtered under normal processing conditions and the fetuses were removed. German Angus, a typical beef cattle; Galloway, a smaller, environmentally resistant beef type; Holstein Friesian, a dairy type; and Belgian Blue, an extreme type for muscle growth were used. Fetuses of each breed were investigated at 3, 6, and 9 mo of gestation. Fetuses were weighed and dissected into carcass, organs, and muscles. Body fat weight was obtained using the Soxhlet extraction method. Fetal weight increased most rapidly in the third trimester of gestation mainly due to the accelerated muscle and fat deposition. The organ weight to body weight (BW) ratios decreased and the muscle and fat weight to BW ratios increased. At 3 mo of gestation, Galloway fetuses had the significantly smallest BW, half-carcass weight, leg weight, organ weight, muscle weight and shortest leg length. In contrast, Holstein fetuses had the significantly greatest BW, liver, kidney, and lung weights and significantly longest leg length among the 4 breeds, but no differences between Holstein Friesian and Belgian Blue were detected in half-carcass and leg weight. Indeed, Belgian Blue fetuses had the significantly greatest half-carcass weight, leg weight, and muscle weight at 9 mo of gestation, and Galloway had a significantly greater body fat to BW ratio than Holstein Friesian and Belgian Blue. These differences were not evident at 3 and 6 mo of gestation. These data show that the profound increase of tissue and organ weights occurred in later gestation in cattle fetuses even though breed differences were evident as early as 3 mo of gestation. Depending on the tissue of interest, impacting fetal growth likely needs to occur early in gestation before the appearance of breed-specific differences.

• Korean Journal of Adult Nursing
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• v.12 no.3
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• pp.396-406
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• 2000

The purpose of the study was to investigate Body Mass Index (BMI), the perception of weight problem and the level of self-esteem and depression in high school and college females. The convenience sample consisted of 303 high school females and 481 college females. Data were collected between November 1999 and December 1999. Subjects ranged in age from 15 years and 26 years. BMI was calculated based on the subject's self-reported body weight and height. Self-perception of having a weight problem was evaluated by a single item question. The Rosenberg's Self-Esteem Scale and the Center for Epidemiologic Studies Depression Scale were utilized to measure the level of self-esteem and depression symptoms. BMI mean scores were 19.92 and 19.83 in high school females and college females, respectively. Based on BMI, 79.2 percent of high school females and 85.2 percent of college females were in a normal weight range. Only 2.6 percent of high school females and 1.5 percent college females were obese. Both high school and college females perceived their body weight problem as moderately severe. The mean scores of depression were 20.33 in high school females and 21.69 in college females. Sixty percent of high school females were depressed and 73.4 percent of college students. There was no significant difference between two groups in BMI. However, high school females perceived their weight problem more severe than college females. College females had higher levels of self-esteem and depression than high school females. BMI and perceptions of weight problem revealed a positive relationship in both groups. Results of the study revealed that a perception of weight problem contributed significantly to predict the level of self-esteem and depression in both groups. BMI score had significant effect on only college females' self-esteem. In the study, even though the mean score of BMI was in a normal range, subjects perceived their weight problems as moderatley severe. Since the perception of a weight problem influenced the level of self-esteem and depression, health care providers need to teach them about the normal weight range in BMI criteria.

• Journal of Korean Foot and Ankle Society
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• v.4 no.1
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• pp.5-12
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• 2000

Purpose: The purpose of this study is to assess the amount of changes in the foot size on weight bearing in adult women, which might help in choosing an appropriate size of the shoes. Materials and Methods: The authors measured the length and width of the feet of 200 healthy women on weight bearing and non-weight bearing, and the size of the shoes they wore. Results: Foot length and width differences between right and left sides were 2.53 mm and 2.16 mm respectively on non-weight bearing, and 2.47 mm and 1.77 mm respectively on weight bearing. Foot length and width increased by 2.89% and 7.50% respectively on weight bearing than those on non-weight bearing. Shoe width was 6.82% longer and 9.54% narrower than the weight bearing foot size. There were 25 women who had shoe-related foot pain, all of them wore shoes that were 13.01 % or more narrower than the weight bearing foot width. Foot pain was significantly correlated with the shoe-foot width difference(p=0.0001). Conclusion: The foot size was increased by 2.89% in length and 7.50% in width with weight bearing. The width of their shoes was narrower. than the weight bearing foot width. Shoe-related foot pain was correlated with the foot-shoe width difference.

• Clinical and Experimental Pediatrics
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• v.51 no.3
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• pp.233-236
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• 2008

In recent years, Korea has experienced a steadily declining birth rate, which is a serious social problem in the country. Although living conditions have improved, the birth rates for low birth weight infants and preterm babies has increased because more and more women choose to give birth later in life and the social environment has changed. The rise in low birth weight infants may increase infant mortality rates and morbidity rates. However, the recent improvements in neonatal care has elevated the survival rate of low birth weight infants up to 90 percent and lowered the weight of the very low birth weight infants that can now be saved. In this study, we used dynamic population statistics from the Korea National Statistical Office, which represents the current trend of social stratification and the population of this period. We analyzed birth records for a seven-year period and studied the changes in the delivery rate of preterm and low birth weight infants and the problems related to those changes. The results show that the rate of low birth weight infants has increased from 3.79% to 4.35% for the past seven years. The rate of preterm babies rose from 3.79% to 4.89%. The number of babies born from mothers aged 35 or more went up from 6.69% to 11.83% of the total number of the babies born. As maternal age has risen, the risks of delivering a preterm or low birth weight infant have also increased.

• Korean Journal of Community Nutrition
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• v.4 no.4
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• pp.554-560
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• 1999

This study was conducted to find adolescent females perception of body image. The survey was carried out by self-questionnaires with 463 female school and college students in Daegu. Analysis of data was done using t-test, and ANOVA with the SAS computer program. The average height, weight and BMI of the subjects were 161.2cm, 53.4kg and 20.51kg/$m^2$. It appeared that 33.3% of the subjects were off the normal range of body weight ; in particular 25.1% of the subjects were under weight. While the subjects’perception of their own current body image was not distorted, they were dissatisfied with their body image because they wanted a very thin figure. Subjects were divided into 3 groups -underweight, normal weight, overweight-according to their current body size. Their perceptions of ideal and desired figures differed significantly between the groups, but they thought a thinner figure than normal body image as ideal and desired body image even in overweight group. As a result, dissatisfaction of body image in the overweight group was significantly larger than the normal-weight group, and that of the normal-weight group was larger than the underweight group. Percentages of weight control attempt were 51.7% and 64.7% in the normal weight and underweight subjects, respectively. Subjects were divided into 2 groups according to their weight control experience : those who have attempted, and who have not attempted. Weight control attemptees had a higher level of dissatisfaction with their body image than non-attemptees, both because weight control attemptees were fatter, and they perceived a thinner figure as an ideal and as a desired body image thin non-attemptees. From the results of this study, we confirmed that one of reasons of excessive weight control behavior among adolescent females was distorted perception about ideal body image.

• The Korean Journal of Food And Nutrition
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• v.20 no.3
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• pp.325-333
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• 2007

This study was conducted to investigate the weight concerns of female university students living in Jeonju, as well as their control on behavior. Self-administered questionnaires were collected from 285 students. Statistical data analysis was completed using the SPSS v. 11.0 program. The results are summarized as follows: The average weight, height, and BMI of the subjects were 21.43 kg, 161.93 cm, and 19.8, respectively. With regard to body image, most were dissatisfied with their figures, especially the hips and thighs. About 42% of the students estimated their figures as 'slightly fat', while 5.4% stated 'very fat', even though their BMI classified as 'normal'. Four percent of the underweight students described themselves as being 'fatty'. Approximately 93% of the students had strongly pursued weight control, and 45.3% reported wanting to lose about $2{\sim}5$ kg. Almost 73% of the respondents had weight loss experience. The primary reason for weight control was to improve self-confidence. Only 19.6% had succeeded in losing weight, while nearly 48% had stopped dieting. To reduce weight, about two thirds of the students ate less(e.g. no snacks, no sweets). Fifty percent tried to reduce weight by more physical activity(e.g. sports). Television(50.9%), friends(48.4%), and newspapers/magazines(40.4%) were essential sources of pertinent information. In conclusion, the results show that female students in Jeonju have a great interest in weight reduction. Thus, the majority are willing to try several methods for weight reduction, which however, are not promising and not based on a lasting nutritional change. Therefore, it's necessary to increase cooperation among those concerned(e.g. dietitians, teachers, parents, media) and to develop weight-control programs that take into consideration lifestyle and daily habits, as well as combine physical activity, nutrition, and behavioral and personality training.