• Journal of Animal Reproduction and Biotechnology
• /
• v.39 no.2
• /
• pp.121-130
• /
• 2024

Background: This study focused on reproductive traits in Hanwoo cattle, specifically the environmental factors affecting gestation length and birth weight. Methods: The records of 1,540 cows calved at the Hanwoo Research Institute from 2015 to 2023 were examined. This study analyzed two populations, line-breeding Hanwoo (LBH) and general Hanwoo (GH), with all cows undergoing estrus synchronization and artificial insemination. The R software was used to compare the differences between the two populations and analyze the environmental factors affecting each trait. Results: The results showed that the average gestation length for LBH was 283.28 ± 5.93 days, which was significantly shorter than that of the GH, which had an average of 285.63 ± 6.21 days (p < 0.001). The average birth weight of LBH calves was 25.10 ± 3.69 kg, significantly lighter than GH calves, which weighed 27.26 ± 4.11 kg on average (p < 0.001). Analysis of environmental factors revealed significant differences in the gestation length of LBH based on dam parity, year, and season of calving. However, no significant differences were observed based on calf sex. For LBH, birth weight showed significant differences based on dam parity, year of calving, and sex of the calf, but not the season of calving. In GH, gestation length varied with dam parity and calving season, but not with calving year or calf sex. The GH birth weight showed differences based on dam parity, year of calving, and calf sex, but not the season of calving. Conclusions: Reproductive traits in the Hanwoo cattle industry are economically vital but are heavily influenced by environmental factors due to their low heritability. An accurate evaluation of the genetic potential of these traits requires an analysis of the environmental factors affecting them. The results of this study serve as foundational data for predicting the potential for genetic improvement in the gestation length and birth weight of Hanwoo cattle.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.12 no.1
• /
• pp.1-10
• /
• 1999

In this paper, we have investigated the effects of the environmental factors on Low Molecular Weight (LMW) silicone fluid contents existing in high temperature vulcanized (HTV) silicone rubber sample, using dipping method and contact angle, current measurement. Artificial treatments such as immersion in water, elevated temperature, UV irradiation and dry band arcing under salt-fog condition are selected as the environmental factors. This results will be helpful to investigate the degradation with time and to expect a life time, because the LMW silicone content, which is important to recovery the hydrophobicity of silicone rubber surface, show different results by each environmental factors.

• Journal of Nutrition and Health
• /
• v.37 no.1
• /
• pp.52-60
• /
• 2004

This study was conducted to investigate the bone mineral density (BMD) and the anthropometric measurements, socioeconomic factors, family history of osteoporosis and other environmental factors affecting BMD in children. One hundred sixty children (80 males, 80 females) in second grade of elementary school in Seoul were recruited; the mean age was 7.7 $\pm$ 0.47 years. Bone mineral density was measured in the lumbar spine (LS), femoral neck (FN), femoral trochanter (FT), and Ward's triangle (WT) by Dual Energy X-ray Absorptiometry (DEXA). Socioeconomic factors, family history of osteoporosis, and other environmental factors were assessed by questionnaire. Bone mineral densities of LS, FN, FT, and WT were 0.677, 0.637, 0.618, and 0.658 g/$\textrm{cm}^2$. BMD of boys was higher than that of girls (LS: 0.685 vs. 0.669, FN: 0.660 vs. 0.614, FT: 0.632 vs. 0.604, WT: 0.678 vs. 0.639 g/$\textrm{cm}^2$). Anthrometric measurements (height, weight relative body weight, circumference of waist and hip) were positively correlated with BMD. With increasing family income, BMD of LS was significantly lowered, and negative correlation was observed between mother's age at birth of subject and the BMD of FN. And the BMD of children with a family history of osteoporosis was significantly lower. However BMDs were not different by educational level of parents, family pattern, delivery term, birth weight, and type of feeding. Further studies are needed to clarify the factors affecting BMD of children and earlier age, included infants and even prenatal life. If any association is revealed and persist until the attainment of peak bone mass, osteoporosis prevention programs are needed to be start very early in the life cycle.

• Journal of Nutrition and Health
• /
• v.38 no.3
• /
• pp.242-250
• /
• 2005

This study was conducted to assess the bone mineral density (BMD) and the anthropometric measurements, life style, and other environmental factors affecting BMD in Korean adolescents. Subjects were 167 high school students (83 male students, 84 female students) in Seoul. BMD was measured in the lumbar spine (LS), femoral neck (FN), femoral trochanter (FT), and Ward's triangle (WT) by dual energy x-ray absorptiometry (DEXA). The questionnaire was used to assess the anthropometric measurements, life style, and other environmental factors. Bone mineral density of LS, FN, FT and WT were 0.967, 0.960, 0.795, $0.761 g/{\cal}cm^2$. The BMD of LS was not different by sex but the male students's BMD of FN, FT and WT were higher significantly than the female students (LS: 0.976 vs. 0.958, FN: 1.040 vs. 0.880, FT: 0.842 vs. 0.749, WT: 0.827 vs. $0.695 g/{\cal}cm^2$) Female students's BMD of LS, FN, WT, and FT was positively correlated with weight but male students's BMD of WT was not correlated with weight. The factors such as the life style, activity and exercise have significant influence on BMD. This study confirms that the major factor affecting BMD was body weight and the factors such as the life style, activity and exercise is related to accumulation of BMD. The classification of sexual characteristics is needed for further studies on BMD of adolescents.

• Economic and Environmental Geology
• /
• v.35 no.1
• /
• pp.67-74
• /
• 2002

The purpose of this study is to determine the weights of the factors for landslide susceptibility analysis using artificial neural network. Landslide locations were identified from interpretation of aerial photographs, field survey data, and topography. The landslide-related factors such as topographic slope, topographic curvature, soil drainage, soil effective thickness, soil texture, wood age and wood diameter were extracted from the spatial database in study area, Yongin. Using these factors, the weights of neural networks were calculated by backpropagation training algorithm and were used to determine the weight of landslide factors. Therefore, by interpreting the weights after training, the weight of each landslide factor can be ranked based on its contribution to the classification. The highest weight is topographic slope that is 5.33 and topographic curvature and soil texture are 1 and 1.17, respectively. Weight determination using backprogpagation algorithms can be used for overlay analysis of GIS so the factor that have low weight can be excluded in future analysis to save computation time.

• Journal of Forest and Environmental Science
• /
• v.32 no.3
• /
• pp.262-269
• /
• 2016

The purposes of this study are to calculate the green and dried weight using wood discs, to figure out weight change on air drying times, and to develop the model of wood disc weight change for Larix kaempferi, Pinus koraiensis, and Pinus densiflora. The variables affecting the weight change were investigated, and the pattern of weight change over time was figured out through linear models. When comparing the stem green weight calculated using wood discs in this study with the weight table of Korea Forest Service, the weight was not significantly different for L. kaempferi and P. koraiensis. On the other hand, in comparison of stem dried weight, the weight was significantly different in all of three species. In addition, various measurement factors were examined to figure out the relationship with weight change, and air drying times and disc diameter were found as significant independent variables. Finally, two linear models were developed to estimate air drying times of three species, fit statistics were significant for practical use.

• Journal of Nutrition and Health
• /
• v.19 no.1
• /
• pp.41-51
• /
• 1986

The prevalence of obesity and its related factors in adolescent girls in Seoul area were investigated from April, 18 to June, 29 1985 bymeans of anthropometry, dietary intakes and general environmental factors. Nine hundred and sixty junior high school girls were selected and invterviewed for 24-hour food intakes. Weight, height, a 우 skinfold thickness(triceps, abdominal) were measured and information on the general backgroun of the subjects were obtained by questinnaire. Subjects were divided into six groups according to their relative weights. It was observed that majority of the parents were under fifty years old and had high school education . In general, father was older and higher in educational levels than mother. Two thirds of subjects lived in their own houses and had three to four siblings. AVerage weight and height of subjects were 46.0kg and 154.4cm, which were higher than Korean natianl average. Average relative weight was 29.75 and average Kaup index was 1.925. Skinfold thickness was 13.4mm fo rtricepts and 16.4mm for abdominal . Prevalence of obesity was 12.9% and 4.8% by criteria of relative weight and skinfold thickness. Average intakes of most of nutrients except iron were acceptable but about one third of the subjects had less than 2/3 of RDa for calcium, iron, vitamin A, and riboflavin. As a whole, prevalence of obesity in this study was higher than those observed in the past surveys. Relationship of dietary intakes and general environmental factors that seemed to influence the obesity were integrated as such. As parents educational levels were higher, it tended to be higher in living standard and have fewer family members and siblings. These may influence more nutrient intakes so that fatness of the subjects seemed to be greater. In the meantime, parents fatness was closely related to those of children indicating an involvement of genetic factors. And also, food habits of individuals such as frequency of snack and bedtime snack were related to fatness significantly.

• Asian-Australasian Journal of Animal Sciences
• /
• v.23 no.3
• /
• pp.302-307
• /
• 2010

The present study aimed to investigate the effects of maternal factors on body weight at hatching (day-old) and at six weeks of age in a commercial broiler line. A total of 6,765 records on body weight at day-old (BWTDO) and 115,421 records on body weight at six weeks of age (BWT6W), originated from a commercial broiler line during 14 generations, were used to estimate genetic parameters related to the effects of maternal traits on body weight of chicks immediately after hatch or six weeks thereafter. The data were analyzed using restricted maximum likelihood procedure (REML) and an animal model with DFREML software. Direct heritability ($h^{2}{_a}$), maternal heritability ($h^{2}{_m}$), and maternal environmental variance as the proportions of phenotypic variance ($c^{2}$) for body weight at day-old were estimated to be 0.050, 0.351, and 0.173, respectively. The respective estimated values for body weight at six weeks of age were 0.340, 0.022, and 0.030. The correlation coefficient between direct and maternal genetic effects for six-week-old body weight was found to be -0.335. Covariance components and genetic correlations were estimated using a bivariate analysis based on the best model determined by a univariate analysis. Between weights at hatching and at six week-old, the values of -0.07, 0.53 and 0.47 were found for the direct additive genetic variance, maternal additive genetic variance and permanent maternal environmental variance, respectively. The estimated correlation between direct additive genetic effect influencing weight at hatch and direct additive maternal effect affecting weight at six weeks of age was -0.21, whereas the correlation value of 0.15 was estimated between direct additive maternal effect influencing weight at hatch and direct additive genetic effect affecting weight at six-week-old. From the present findings, it can be concluded that the maternal additive genetic effect observed for weight at six weeks of age might be a factor transferred from genes influencing weight at hatch to weight at six-week-old.

• The Journal of Pediatrics of Korean Medicine
• /
• v.25 no.3
• /
• pp.57-69
• /
• 2011

Objectives: Purpose of this study is to analyze and to estimate which and how much genetic and environmental factors have affected on growth. Also, a method of final height prediction can be developed from this study results. Methods: Correlation analysis and categorical regression analysis were conducted between genetic and environmental factors correlated with the final adult height, through survey from 171 male. Results: Mid parental height, neonatal body weight, intake frequency of beef, chicken, milk, fruits and coffee, sleep quantity and quality during the elementary school and sleep quantity during the middle school have affected on the final adult height. And a regression equation with 0.494 for coefficient of determination was obtained. Conclusions: Mid-parental-height has the most affected on the final adult height. Among environmental factors, food and sleep have significantly affected, but exercise doesn't. Among foods, meal, beef, and milk intake have remarkably affected on the final height, and chicken and fruit also have affected in some degree, but coffee has affected badly. Among sleep habits, sleep quantity during the elementary school has the most affected, sleep quality during the elementary school and sleep quantity during the middle school also have affected in some degree on final height. The younger the age is, the more sleep have affected and sleep quantity have more affected than sleep quality. Neonatal weight also has remarkably affected on the final height. Through this analysis, the final adult height can be predicted using regression equation which covers 49.4% of genetic and environmental factors.

• Journal of Korean Society for Atmospheric Environment
• /
• v.23 no.E2
• /
• pp.47-56
• /
• 2007

Among all the nitrogen species present in the atmosphere, ammonia forms a considerable portion along with the nitrogen oxides. The major sources of atmospheric ammonia are animal feedlot operations including emission from excreta of domestic animals and agricultural activities, followed by emission from synthetic fertilizers, biomass burning and to some lesser extent, fossil fuel combustion. Ammonia emission factor, expressed as the weight of ammonia per unit weight, volume, or duration of the activity emitting it, is generally used in developing emission estimates for emission inventories. The factors determining ammonia loss from soil or from manures are the temperature, pH, humidity, precipitation and the velocity of wind above it.