• Asian-Australasian Journal of Animal Sciences
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• v.17 no.2
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• pp.153-158
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• 2004

Data containing 14,188 lactation and reproductive records of Korean Holstein cows at first parity distributed across 3,734 herd-year-season groups were analyzed to get genetic (co)variance estimates for milk yield, fat yield, calving ease, and days open. Milk and Fat yields were adjusted to 305 d. Heritabilities and genetic correlations were estimated in two different animal models on which were included direct genetic effects (Model 1) and direct+maternal genetic effects (Model 2) using REML algorithms. Milk and fat yields were affected by age at first calving as linear and quadratic. Heritability estimates of direct effects were 0.25 for milk yield, 0.17 for fat yield, 0.03 for calving ease and 0.03 for days open in Model 2. These estimates for maternal effects were 0.05, 0.08, 0.04 and less than 0.01 for each corresponding trait. Milk productions at first lactation were to show genetically favorable correlation with calving ease and days open for direct genetic effects (-0.24 - -0.11). Moreover, calving ease was correlated with days open of 0.30 for direct genetic effects. Correlations between direct and maternal effects for each trait were negatively correlated (-0.63 - -0.32). This study suggested that maternal additive genetic variance would be not ignorable for genetic evaluation of milk production as well as reproductive traits such as calving ease and days open at first parity. Furthermore, difficult calving would genetically influence the next conception.

• Korean Journal of Agricultural Science
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• v.43 no.4
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• pp.595-602
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• 2016

In pigs, individuals in the same pen may show aggressive behavior toward each other, such as tail biting. Such social interactions among pen mates may considerably affect their welfare and performance, both in negative and positive ways. The present study was conducted to investigate social genetic effects on days to 90 kg using data from 12,208 Duroc and Yorkshire pigs that were born between 2008 and 2012. Heritability was estimated using the five following animal models: a basic model with direct heritable effects only (Model 1), a social model with direct and social heritable effects (Model 2), a model accounting for covariance between direct and social heritable effects (Model 3), and two models considering a dilution factor with direct and social heritable effects (Models 4 and 5). The optimal model to represent Duroc pigs was Model 1 which only uses direct heritable effects. Direct heritability (0.21) was higher than total heritability (0.09) and covariance was negative. Model 2 was evaluated as the optimum model for Yorkshire pigs. Yorkshire data showed that total heritability (0.5) was twice as high as direct heritability (0.25) and covariance was positive. Our results suggest that the efficiency of social effects differed among breeding lines. Further research on social effects related to breeds by group size would clarify which is the most efficient selection method that accounts for social genetic effects.

• Journal of the Korean Society of Food Culture
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• v.27 no.4
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• pp.331-339
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• 2012

The study examined the moderating effects of the relationship among purchase motivation, satisfaction, and loyalty in a farmer-to-consumer direct market. Data were collected from 426 consumers of direct sale agricultural products who visited nine rural villages across the country. The SPSS 15.0 and LISREL 8.80 statistical package were used for frequency, reliability, exploratory factor, confirmatory factor, and path analysis. Results showed that 'product factor', 'experience factor' and 'economic factor' among purchase motivation had positive effects on satisfaction and satisfaction had positive effects on loyalty. The analysis also indicated that gender moderated the relationship among purchase motivation, satisfaction, and loyalty. Whereas product and economic factors among purchase motivations had positive effects on satisfaction in the male group, product and experience motivation were important factors for female group. These results could enable direct sales marketers to develop marketing techniques to expand farm sales.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.7
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• pp.961-966
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• 2008

Direct and maternal genetic parameters for production traits in 1,642 pigs and maternal genetic correlations among production (1,642 pigs) and feed efficiency (380 boars) traits were estimated in 7 generations of a Duroc population. Traits studied were daily gain (DG), intramuscular fat (IMF), loineye area (LEA), backfat thickness (BF), daily feed intake (FI), feed conversion ratio (FCR) and residual feed intake (RFI). The RFI was calculated as the difference between actual and predicted feed intake. The predicted feed intake was estimated by adjusting the initial test weight, DG and BF. Data for production traits were analyzed using four alternative animal models (including direct, direct+maternal permanent environmental, or direct+maternal genetic+maternal permanent environmental effects). Direct heritability estimates from the model including direct and all maternal effects were $0.41{\pm}0.04$ for DG, $0.27{\pm}0.04$ for IMF, $0.52{\pm}0.06$ for LEA and $0.64{\pm}0.04$ for BF. Estimated maternal heritabilities ranged from $0.04{\pm}0.04$ to $0.15{\pm}0.05$ for production traits. Antagonistic relationships were observed between direct and maternal genetic effects ($r_{am}$) for LEA (-0.21). Maternal genetic correlations of feed efficiency traits with FI ($r_g$ of FI with FCR and RFI were $0.73{\pm}0.06$ and $0.90{\pm}0.05$, respectively) and LEA (rg of LEA with FCR and RFI were $-0.48{\pm}0.05$ to $-0.61{\pm}0.05$, respectively) were favorable. The estimated moderate genetic correlations between direct and maternal genetic effects for IMF and LEA indicated that maternal effects has an important role in these traits, and should be accounted for in the genetic evaluation system.

• Journal of the Korean Home Economics Association
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• v.48 no.7
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• pp.33-48
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• 2010

The purpose of this study was to explore the effects of family structure(parentral marital status and socioeconomic status), parental communication, academic problems, and peer relationship on juvenile delinquency. The participants were 1009 middle school and high school students in Seoul city and Gyeonggi Province. The major results were as follows: 1) Parental marital status(divorced/seperated) had both direct and indirect positive effects and lower class in socioeconomic status had an indirect positive effect on academic problems and peer relationship on juvenile delinquency rates. 2) Open maternal communication had a direct negative effect on juvenile delinquency rates. However, open paternal communication had both direct and indirect negative effects. 3) Academic problems had both direct and indirect positive effects on juvenile delinquency rates. 4) Peer relationship had a direct positive effect on juvenile delinquency rates. 5) The level of effects that each variable had differed by delinquency types. Based on these results, implications for preventing juvenile delinquency were discussed.

• Asian-Australasian Journal of Animal Sciences
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• v.11 no.4
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• pp.441-444
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• 1998

The negative direct-maternal genetic correlation $(r_{dm})$ for weaning weight is inflated when data are analyzed with model ignoring sire-by-year interactions (SY). An analytical study investigating the consequences of ignoring SY was undertaken. The inflation of negative correlation could be due to a functional relationship of design matrices for additive direct and maternal genetic effects to that for sire effects within which SY effects were nested. It was proven that the maternal genetic variance was inflated by the amount of reduction for sire variance; the direct genetic variance was inflated by four times the change for maternal genetic variance; and the direct-maternal genetic covariance was deflated by twice the change for maternal genetic variance. The findings were agreed to the results in previous studies.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.287-287
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• 2007

The ferroelectric and electric properties of UV-irradiated bismuth lanthanum titanate (BLT) films prepared using photosensitive starting precursors were characterized. The effects of lanthanum doping on ferroelectric and electric properties were investigated by polarization-electric field hysteresis loops and leakage current-voltage measurements. X-ray diffractometer and ellipsometry were served to provide the information about the crystalline structure and thickness of the films after annealing. The images of the surface microstructure and direct-patterned BLT films were observed by using scanning electron microscopy. The effects of lanthanum doping on the electric properties of direct-pattern able BLT films and their direct-patterning were studied.

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

• Journal of Korean Society of Industrial and Systems Engineering
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• v.35 no.2
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• pp.80-87
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• 2012

It is well known that ISO 9001 and TQM have significant effects on business success. We analyzed the effects of ISO 9001 requirements and TQM on financial performance with structural equation modeling. Hypotheses are proposed and tested based on existing beliefs, proposition and prior research concerning quality. Survey data were collected from 291 manufacturing companies with ISO 9001 certifications. The data show that ISO 9001:2008 requirements have significant positive direct effects on TQM practices, but do not have positive direct effects on financial performance. As expected, TQM has significant positive direct effects on financial performance. One of the important results is that efforts to meet ISO 9001:2008 requirements enhance TQM practices which, in turn, helps to improve financial performance. Findings in this study support the claims that ISO 9001:2008 would be a good step toward total quality management and is a meaningful component of TQM.

• Korean Journal of Child Studies
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• v.37 no.5
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• pp.65-82
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• 2016

Objective: The main purpose of this study was to examine the direct and indirect effects of parent-adolescent communication (through adolescent optimism) on adolescent conflict-coping styles. Methods: A total of 337 high school students participated in this study. They completed questionnaires about communications with their parents and their own optimism and conflict-coping styles. Data were analyzed using t-tests, correlations, and SEM. Results: Neither father- nor mother-adolescent communication had direct effects on adolescent conflict-coping styles. However, mother-adolescent communication had an indirect effect on conflict-coping styles, mediated by adolescent optimism. Adolescents who had open communication with mothers displayed higher levels of optimism, which led to more positive conflict-coping styles. In addition, multigroup analyses revealed that there were significant gender differences in direct and indirect effects. For boys, mother-adolescent communication directly influenced adolescent conflict-coping styles; however, father-adolescent communication did not directly or indirectly affect adolescent conflict-coping styles. For girls, neither father- nor mother-adolescent communication had direct effects on conflict-coping styles; only optimism had a significant effect on conflict-coping styles. Conclusion: The findings from this study suggest that communication with mothers and fathers have different effects on adolescents' conflict-coping styles. These findings have implications for future research and practice by emphasizing the importance of parent-adolescent communication and optimism in designing conflict-coping programs for adolescents.