• Journal of Korean Society of Water and Wastewater
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• v.24 no.5
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• pp.549-560
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• 2010

Recently, heavy rainfalls due to the climate change in Korea have caused inundation problems in urban sewer networks. In july 2006, a flooding accident at Misari motorboat racing stadium near the Han river occurred due to the effect of record-breaking outflow discharge from Paldang-dam. The purpose of this study was to simulate and analyze the flooding accident at Misari stadium by MOUSE model. The results of simulation analysis indicated that the total flood volume was $1,313,450m^3$. The effect of back water was 85.9% of the total volume which was caused by the manhole accident, and the effect of accumulated runoff was 14.1% of total volume which was caused by non-return valve shutdown. The simulation results of this MOUSE modeling that was linked to the boundary condition of the dynamic flows in the river by DWOPER model showed the potential of successful inundation analysis for sewer networks.

• Journal of Life Science
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• v.31 no.9
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• pp.840-848
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• 2021

This study was conducted to estimate annual trends and the environmental effects in the racing records of Jeju horses. The Korean Racing Authority (KRA) collected 48,645 observations for 2,167 Jeju horses from 2002 to 2019. Racing records were preprocessed to eliminate errors that occur during the data collection. Racing times were adjusted for comparison between race distances. A stepwise Akaike information criterion (AIC) variable selection method was applied to select appropriate environment variables affecting racing records. The annual improvement of the race time was -0.242 seconds. The model with the lowest AIC value was established when variables were selected in the following order: year, budam classification, jockey ranking, trainer ranking, track condition, weather, age, and gender. The most suitable model was constructed when the jockey ranking and age variables were considered as random effects. Our findings have potential for application as basic data when building models for evaluating genetic abilities of Jeju horses.

• Journal of Veterinary Clinics
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• v.15 no.2
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• pp.427-431
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• 1998

This study was undertaken to investigate the effect of exercise induced pulmonary hemorrhage(EIPH) on the finishing position of racehorses, 400 bleeders(305: 1 time, 76: 2 times, 19: 3 times, total: 514 cases) which had bled(EIPH) from their nostrils after their races at the Seoul racecourse during the 5 years period('93-'97) were analyzed for this study. The ratio of bleeders to total racehorses in finishing position 1-3,4-6, 7-9 or above 10 was 0.55, 0.84, 0.90 or 1.13%, respectively. There is tendency to higher incidence of bleeding in the later positioned racehorses group. To analyze the correlation between EIPH and finishing position, finishing potion of each EIPHed horses' was checked at 7 successive races(3 races each before/after EIPH. The average final position at the -3rd race, -2nd racer -lst racer EIPHed race, 1st race,2nd race and 3rd race of each bleeder was 5.85. 5.94, 6.21, 7.32, 7.20, 6.51 and 6.53, respectively. Raring times were adjusted to 1,000 m equivalent. Average racing times of the -3rd race,-2nd racer -lst raced EIPHed race, 1st race, 2nd race and 3rd race of each bleeder was 67.1, 67.1, 67.2, 67.6, 67.5, 67.4 and 67.3 second, respectively. Bleeders which finished the race within 1 second following the winners were 25. 3% of total bleeders. The rest 74.7% reached at the finish line 1 second later than the winners. Particularly 46.3% of bleeders were above 2 second later. Therefore this study suggested that bleeding has effect on performance of the racehorse, consequently it make bleeders be placed later positions.

• Journal of Life Science
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• v.31 no.12
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• pp.1088-1093
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• 2021

Jeju horse (Equus ferus caballus) is a Korean horse breed that has been native to Jeju Island for a long time. Jeju horses are used as racehorses, and their racing ability is a major economic trait. The role of the myostatin (MSTN) gene in skeletal muscle mass has been studied in various mammals, and mutations in the MSTN gene are known to affect the racing ability and stamina of thoroughbreds. In this study, we compared the frequency of mutations in the MSTN gene in several horse breeds, including 1,433 Jeju horses. Among the mutations (ECA18 g.66493737C>T) in the MSTN gene, the long-distance aptitude genotype (TT) was found to have a frequency of 0.826 in Jeju horses, which was higher than that in Halla horses (0.285) and thoroughbreds (0.252). The genotypes and arrival records of Jeju horses were compared according to various distances (400 m, 800 m, 900 m, 1,000 m, 1,110 m, and 1,200 m). According to the results, the CT type showed a faster-reaching record than the TT type in races of less than 1,000 m. However, almost identical results were confirmed in races over 1,110 m. This study suggests that the MSTN mutation in Jeju horses may be related to race distance aptitude. In future research, the data in this study can be used for developing markers related to race distance aptitude and racing abilities in Jeju horses.