• Journal of Korean Society of Steel Construction
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• v.18 no.5
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• pp.563-574
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• 2006

The objective of this study is to determine the effect of the loading size on displacements of stiffened plates with open ribs using the orthotropic rigidity ratio as the parameter. To analyze the displacement behavior of stiffened plates according to the loading size, a concentrated load and three types of uniform distributed loads were applied on the rib at the center of some plates. The results of the analysis of various stiffened plates show that the central displacement ratio of the distributed load to the concentrated load increased according to the decrease in the loading size, and that the ratio can be expressed as a function of the rigidity ratio for each rib space. The maximum displacement of the stiffened plate subjected to the distributed load did not appear at the center of the plate due to the local behavior, and the increasing ratio of the maximum displacement to the central displacement can be expressed as a function of the rigidity ratio for each rib space. Orthotropic plate analysis can achieve more accurate results using the proposed functions, and the application of the functions to examples of a different aspect ratio and support condition shows good accuracy. Therefore, using the functions proposed in this study, the central and maximum displacements can easily be achieved in the orthotropic plate analysis of stiffened plates subjected to the distributed load.

• Journal of Radiation Protection and Research
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• v.28 no.4
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• pp.311-319
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• 2003

We developed a grid-based Gaussian plume model to evaluate tracer release data measured at Young Gwang nuclear site in 1996. Downwind distance was divided into every 10m from 0.1km to 20km, and crosswind distance was divided into every 10m centering released point from -5km to 5km. We determined dispersion factors, ${\sigma}_y\;and\;{\sigma}_z$ using Pasquill-Gifford method computed by atmospheric stability. Forecasting ability of the grid-based Gaussian plume model was better at the 3km away from the source than 8km. We confirmed that dispersion band must be modified if receptor is far away from the source, otherwise P-G method is not appropriate to compute diffusion distance and diffusion strength in case of growing distance. So, we developed an empirical equation using linear programming. An objective function was designed to minimize sum of the absolute value between observed and computed values. As a result of application of the modified dispersion equation, prediction ability was improved rather than P-G method.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.4
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• pp.470-475
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• 2013

The objective of this study was to estimate genetic parameters that are to be used for across-herd genetic evaluations of seed stock pigs at GGP level. Performance data with pedigree information collected from swine breeder farms in Korea were provided by Korea Animal Improvement Association (AIAK). Performance data were composed of final body weights at test days and ultrasound measures of back fat thickness (BF), rib eye area (EMA) and retail cut percentage (RCP). Breeds of swine tested were Landrace, Yorkshire and Duroc. Days to 90 kg body weight (DAYS90) were estimated with linear function of age and ADG calculated from body weights at test days. Ultrasound measures were taken with A-mode ultrasound scanners by trained technicians. Number of performance records after censoring outliers and keeping records pigs only born from year 2000 were of 78,068 Duroc pigs, 101,821 Landrace pigs and 281,421 Yorkshire pigs. Models included contemporary groups defined by the same herd and the same seasons of births of the same year, which was regarded as fixed along with the effect of sex for all traits and body weight at test day as a linear covariate for ultrasound measures. REML estimation was processed with REMLF90 program. Heritability estimates were 0.40, 0.32, 0.21 0.39 for DAYS90, ADG, BF, EMA, RCP, respectively for Duroc population. Respective heritability estimates for Landrace population were 0.43, 0.41, 0.22, and 0.43 and for Yorkshire population were 0.36, 0.38, 0.22, and 0.42. Genetic correlation coefficients of DAYS90 with BF, EMA, or RCP were estimated to be 0.00 to 0.09, -0.15 to -0.25, 0.22 to 0.28, respectively for three breeds populations. Genetic correlation coefficients estimated between BF and EMA was -0.33 to -0.39. Genetic correlation coefficient estimated between BF and RCP was high and negative (-0.78 to -0.85) but the environmental correlation coefficients between these two traits was medium and negative (near -0.35), which describes a highly correlated genetic response to selection on one or the other of these traits. Genetic Trends of all three breeds tend to be towards bigger EMA or greater RCP and shorter DAYS90 especially from generations born after year 2000.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.7
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• pp.924-929
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• 2004

The objective of this study were to investigate the effect of ejaculation frequency on semen characteristics and to establish a method for quick assessment of sperm concentration in TCC using packed cell volume (PCV) as the parameter (Trial 1). Eighty senior roosters, averaging 61 wk-old, were used and the sperm concentrations were determined using a hemacytometer. The PCV value was measured in a capillary (0.75 mm in inner diameter) by centrifugation. A simple linear regression analysis suggested that the sperm concentrations were significantly correlated with PCV values (r=0.62, p<0.001). Trial 2 was conducted to determine the optimal ejaculation frequency of TCC roosters in a weekly semen collection program. The male birds were subjected to 1, 2, 3 or 6 ejaculations per week for four consecutive weeks and semen characteristics including ejaculation volume (EV, mL), sperm motility (%), PCV (%), sperm concentration (ESC, $\times$10$^{9}$/mL), weekly sperm production (WSP, $\times$10$^{9}$/wk) and average motile sperm numbers (AMSN, $\times$10$^{9}$/ejac) were determined. Average EV was greater in the group with 3 ejac/wk than with only 1 ejac/wk in weeks 1 and 3 of the collection period. WSP increased with ejaculation frequency during the first 3 weeks of collection (p<0.05). Sperm motility was better in the birds with 6 ejac/wk than in single ejaculation group for the first 2 wk and no significant differences were found for the last 2 wk of study. In contrast, the PCV value showed a trend of reduction for the first 2 wks in the 6 ejac/wk group. Surprisingly, no significant differences were detected in the AMSN among treatment groups. The weekly motile sperm production (WMSP) increased with ejaculation frequency. Based on our observation, PCV values could be used for a quick estimation of sperm concentration and an intensive semen collection program enhanced weekly sperm production in TCC roosters.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.10
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• pp.1575-1580
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• 2018

Objective: This study was conducted to estimate the genetic parameters and breeding values of breast meat related traits of Pekin ducks. Selection response was also determined by using ultrasound breast muscle thickness (BMT) measurements in combination with bosom breadth (BB) and keel length (KL) values. Methods: The traits analyzed were breast meat weight (BMW), body weight (BW), breast meat percentage (BMP) and the three parameters of breast meat (BB, KL, and BMT). These measurements were derived from studying 15,781 Pekin ducks selected from 10 generations based on breast meat weight. Genetic parameters and breeding value were estimated for the analysis of the breeding process. Results: Estimated heritability of BMW and BMP were moderate (0.23 and 0.16, respectively), and heritability of BW was high (0.48). Other traits such as BB, KL, and BMT indicated moderate heritability ranging between 0.11 and 0.28. Significant phenotypic correlations of BMW with BW and BMP were discovered (p<0.05), and genetic correlations of BMW with BW and BMP were positive and high (0.83 and 0.66, respectively). It was noted that BMW had positive correlations with all the other traits. Generational average estimated breeding values of all traits increased substantially over the course of selection, which demonstrated that the ducks responded efficiently to increased breast meat yield after 10 generations of breeding. Conclusion: The results indicated that duck BMW had the potential to be increased through genetic selection with positive effects on BW and BMP. The ultrasound BMT, in combination with the measurement of BB and KL, is shown to be essential and effective in the process of high breast meat yield duck breeding.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.2
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• pp.871-876
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• 2014

Objective: Desmogleins (DSGs) are major members among the desmosomal cadherins critically involved in cell-cell adhesion and the maintenance of normal tissue architecture in epithelia. Reports exploring links of DSG family member expression with cancers are few and vary. The aim of this study was to investigate the ratio of DSG2 and DSG3 mRNA expression in esophageal squamous cell carcinoma (ESCC) tissue to normal tissue (T/N ratio) and evaluate correlations with clinical parameters. Methods: The mRNA expression of DSGs, as well as ${\gamma}$-catenin and desmoplakin, was detected by real-time quantitative RT-PCR in 85 cases of ESCC tissue specimens. Results: The expression level of DSG3 mRNA was significantly higher than that of DSG2 in ESCC specimens (p=0.000). DSG3 mRNA expression highly correlated with histological grade (p=0.009), whereas that of DSG2 did not significantly relate to any clinicopathologic parameter. Kaplan-Meier survival analysis showed that only DSG3 expression had an impact on the survival curve, with negative DSG3 expression indicating worse survival (p=0.038). Multivariate Cox regression analysis demonstrated DSG3 to be an independent prognostic factor for survival. Furthermore, correlation analysis demonstrated the mRNA level of DSG3 to highly correlate with those of ${\gamma}$-catenin and desmoplakin in ESCC samples (p=0.000), implying that the expression of desmosomal components might be regulated by the same upstream regulatory molecules. Conclusions: Our findings suggest that DSG3 may be involved in the progression of ESCC and serve as a prognostic marker, while expression of DSG2 cannot be used as a predictor of ESCC patient outcome.

• Atmosphere
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• v.24 no.4
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• pp.565-571
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• 2014

A long-range prediction system of tropical cyclone (TC) activity over the western North Pacific (WNP) has been operated in the National Typhoon Center of the Korea Meteorological Administration since 2012. The model forecasts the spatial distribution of TC tracks averaged over the period June~October. In this study, we separately developed TC prediction models for summer (June~August) and autumn (September~November) period based on the current operating system. To perform the three-month WNP TC activity prediction procedure readily, we modified the shell script calling in environmental variables automatically. The user can apply the model by changing these environmental variables of namelist parameter in consideration of their objective. The validations for the two seasons demonstrate the great performance of predictions showing high pattern correlations between hindcast and observed TC activity. In addition, we developed a post-processing script for deducing TC activity in the Korea emergency zone from final forecasting map and its skill is discussed.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.9
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• pp.1237-1246
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• 2013

The objective of this study was to estimate variance components and genetic parameters for lactation milk yield (LY), lactation length (LL), average milk yield per day (YD), initial milk yield (IY), peak milk yield (PY), days to peak (DP) and parameters (ln(a) and c) of the modified incomplete gamma function (MIG) in an Ethiopian multibreed dairy cattle population. The dataset was composed of 5,507 lactation records collected from 1,639 cows in three locations (Bako, Debre Zeit and Holetta) in Ethiopia from 1977 to 2010. Parameters for MIG were obtained from regression analysis of monthly test-day milk data on days in milk. The cows were purebred (Bos indicus) Boran (B) and Horro (H) and their crosses with different fractions of Friesian (F), Jersey (J) and Simmental (S). There were 23 breed groups (B, H, and their crossbreds with F, J, and S) in the population. Fixed and mixed models were used to analyse the data. The fixed model considered herd-year-season, parity and breed group as fixed effects, and residual as random. The single and two-traits mixed animal repeatability models, considered the fixed effects of herd-year-season and parity subclasses, breed as a function of cow H, F, J, and S breed fractions and general heterosis as a function of heterozygosity, and the random additive animal, permanent environment, and residual effects. For the analysis of LY, LL was added as a fixed covariate to all models. Variance components and genetic parameters were estimated using average information restricted maximum likelihood procedures. The results indicated that all traits were affected (p<0.001) by the considered fixed effects. High grade $B{\times}F$ cows (3/16B 13/16F) had the highest least squares means (LSM) for LY ($2,490{\pm}178.9kg$), IY ($10.5{\pm}0.8kg$), PY ($12.7{\pm}0.9kg$), YD ($7.6{\pm}0.55kg$) and LL ($361.4{\pm}31.2d$), while B cows had the lowest LSM values for these traits. The LSM of LY, IY, YD, and PY tended to increase from the first to the fifth parity. Single-trait analyses yielded low heritability ($0.03{\pm}0.03$ and $0.08{\pm}0.02$) and repeatability ($0.14{\pm}0.01$ to $0.24{\pm}0.02$) estimates for LL, DP and parameter c. Medium heritability ($0.21{\pm}0.03$ to $0.33{\pm}0.04$) and repeatability ($0.27{\pm}0.02$ to $0.53{\pm}0.01$) estimates were obtained for LY, IY, PY, YD and ln(a). Genetic correlations between LY, IY, PY, YD, ln(a), and LL ranged from 0.59 to 0.99. Spearman's rank correlations between sire estimated breeding values for LY, LL, IY, PY, YD, ln(a) and c were positive (0.67 to 0.99, p<0.001). These results suggested that selection for IY, PY, YD, or LY would genetically improve lactation milk yield in this Ethiopian dairy cattle population.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.11
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• pp.1550-1556
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• 2017

Objective: This study estimated the genetic parameters for productive and reproductive traits. Methods: The data included production and reproduction records of animals that have calved between 1979 and 2013. The genetic parameters were estimated using multivariate mixed models (DMU) package, fitting univariate and multivariate mixed models with average information restricted maximum likelihood algorithm. Results: The estimates of heritability for milk production traits from the first three lactation records were $0.03{\pm}0.03$ for lactation length (LL), $0.17{\pm}0.04$ for lactation milk yield (LMY), and $0.15{\pm}0.04$ for 305 days milk yield (305-d MY). For reproductive traits the heritability estimates were, $0.09{\pm}0.03$ for days open (DO), $0.11{\pm}0.04$ for calving interval (CI), and $0.47{\pm}0.06$ for age at first calving (AFC). The repeatability estimates for production traits were $0.12{\pm}0.02$, for LL, $0.39{\pm}0.02$ for LMY, and $0.25{\pm}0.02$ for 305-d MY. For reproductive traits the estimates of repeatability were $0.19{\pm}0.02$ for DO, and to $0.23{\pm}0.02$ for CI. The phenotypic correlations between production and reproduction traits ranged from $0.08{\pm}0.04$ for LL and AFC to $0.42{\pm}0.02$ for LL and DO. The genetic correlation among production traits were generally high (>0.7) and between reproductive traits the estimates ranged from $0.06{\pm}0.13$ for AFC and DO to $0.99{\pm}0.01$ between CI and DO. Genetic correlations of productive traits with reproductive traits were ranged from -0.02 to 0.99. Conclusion: The high heritability estimates observed for AFC indicated that reasonable genetic improvement for this trait might be possible through selection. The $h^2$ and r estimates for reproductive traits were slightly different from single versus multi-trait analyses of reproductive traits with production traits. As single-trait method is biased due to selection on milk yield, a multi-trait evaluation of fertility with milk yield is recommended.

• Journal of Korea Water Resources Association
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• v.50 no.10
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• pp.661-671
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• 2017

The objective of this study was to analyze the flood stage considering the uncertainty caused by the river roughness coefficients and discharge. The methodology of this study involved the GLUE (Generalized Likelihood Uncertainty Estimation) to quantify the uncertainty bounds applying three different storm events. The uncertainty range of the roughness was 0.025~0.040. In case of discharge, the uncertainty stemmed from parameters in stage-discharge rating curve, if h represents stage for discharge Q, which can be written as $Q=A(h-B)^C$. Parameters in rating curve (A, B and C) were estimated by non-linear regression model and assumed by t distribution. The range of parameters in rating curve was 5.138~18.442 for A, -0.524~0.104 for B and 2.427~2.924 for C. By sampling 10,000 parameter sets, Monte Carlo simulations were performed. The simulated stage value was represented by 95% confidence interval. In storm event 1~3, the average bound was 0.39 m, 0.83 m and 0.96 m, respectively. The peak bound was 0.52 m, 1.36 m and 1.75 m, respectively. The recurrence year of each storm event applying the frequency analysis was 1-year, 10-year and 25-year, respectively.