• International Journal of Reliability and Applications
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• v.6 no.1
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• pp.13-29
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• 2005

This paper deals with the stochastic analysis of a three-states semi-Markov reliability model. Using both the maximum likelihood and Bayes procedures, the parameters included in this model are estimated. Next, assuming that the lifetime and repair time are generalized exponential random variables, the reliability function of this system is obtained. Then, the distribution of the first passage time of this system is discussed. Finally, some of the obtained results are compared with those available in the literature.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.5
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• pp.439-446
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• 2017

The Maritime Safety Act established restrictions for the passage of oil tankers, prohibiting vessesl carrying more than 1,500 kiloliters of oil or 1,500 tons of a hazardous liquid substance. Prohibited vessels that do not satisfy the restrictions are allowed to enter and depart from a nearby port from the outer sea area to minimize the time and distance the oil tanker must navigate in the prohibited area. Therefore, such regulation should not be construed as referring to inshore traffic. In this study, the traffic volume of coastal tankers that do not use the approaching channels for specific sea areas near Yeosu and Gwangyang Port was analyzed, and the cargo loads of these ships were investigated. The results of this study should be used to allow tankers to minimize the time and distance of navigation in prohibited areas. According to the survey, 16 vessels, 51.6 % of the 31 vessels using inshore traffic included in the study, were loaded with more than 1,500 tons of cargo. This is not appropriate according to the legislation for oil tanker passage. Therefore, in this study, sea routes have been proposed that connect with the approaching channels of specific sea areas, from the outer sea areas of restricted passages. Regulations have also been proposed for the entry and departure of oil tankers around Yeosu and Gwangyang Port.

• Reproductive and Developmental Biology
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• v.28 no.1
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• pp.1-6
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• 2004

This study was conducted to investigate the effects of donor cell type, individual, passage number and trypsinization time on the in vitro development of bovine somatic cell nuclear transfer embryos. Three cell types (skin, muscle and cumulus cells) and cells from 3 individuals were used for nuclear transfer. Cell were passaged by 5, 15 or 30 times, and cell were trypsinized for 1 or 3 min before injection. Nuclear transfer were performed by conventional fusion method. Development rates to the blastocyst stage were not significantly different among three cell types (16.5∼23.9%) and individuals (16.4∼19.5%). Blastocyst formation rate of cloned embryos reconstituted with cells at passage 30 (5.8%) was significantly lower than those of embryos reconstituted with 5- and 15-passaged cells (25.3 and 23.5%, respectively, P＜0.05). The rate of embryos developed to the blastocyst stage was higher in embryos reconstituted with cells trypsinized for 1 min (30.7%) compared to embryos reconstituted with cells trypsinized for 3 min (P＜0.05). The result of the present study indicates that different donor cell types and individuals used in this study did not affect the development of cloned bovine embryos. However, passage number and trypsinization time of donor cells affect the in vitro development of cloned bovine embryos.

• Journal of the korean academy of Pediatric Dentistry
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• v.43 no.4
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• pp.419-426
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• 2016

For this research 20 supernumerary teeth impacted in the maxillary anterior have been extracted and pulp cells have been collected from them. From the collected pulp cells, total of 17 (10 males, 7 females) have been selected as subjects. From this research, the run-time of successive culture of the cell from tooth number pulp tissue was $2.91{\pm}0.29$ days. From the gathering of cells from the initial pulp tissue until gaining 80% confluency took $4.53{\pm}0.94$ which was the longest. The following successive cultures took $2.73{\pm}0.32$ days. Average runtime for female was $2.81{\pm}0.27$ days whereas male had average runtime of $2.98{\pm}0.29$ days. Average run-time for inversion was $2.94{\pm}0.30$ days and for normal location, $2.80{\pm}0.20$ days. Average runtime was $2.92{\pm}0.31$ days and other forms took $2.88{\pm}0.22$ days. In the future, follow up research would be needed to evaluate the efficiency of the cells collected from the initial passage and the latter passage as stem-cells and taking into consideration the less than 3 days'time for the subculture, it could be concluded that the research efficiency and fast cultivation would be sufficiently effective.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.7
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• pp.1040-1048
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• 1999

Four ruminally fistulated crossbred $(Sahiwal{\times}Holstein\;Friesan)$ adult (~6 yr.) cattle of about $318{\pm}16kg$ body weight were randomly assigned in an experiment based on $4{\times}4$ latin square design to study the effect of different level of barseem (Trifolium alexendrinum) supplementation to wheat straw based diet on intake, digestion, VFA production, eating behaviour and passage rate. Four dietary treatments were wheat straw ad lib. (I), supplementation to wheat either 15(II), 30(III) or 45(IV)% of berseem. Mean total volatile fatty acids (TVFA) concentration in rumen liquor was 58.45, 66.14, 77.92 and 78.64 mmol/l. TVFA concentration in rumen liquor increased significantly (p<0.01) with increased level of berseem supplementation upon 30% level of breseem. Two peaks of TVFA concentration was observed at 4 and 8 h post feeding. Brseem supplementation showed no significant effect on daily time spent for eating, ruminating or idling, chews per minute or number of rumination boli ingested per minute. Time spent for eating and ruminating one kg neutral detergent fibre (NDF) was significantly (p<0.05) less in breseem supplemented groups. Animals in groups I, II, III and IV consumed 26, 34, 47 and 57% of DM within 1st 4 h and 64, 70, 70 and 77% of total DM within 1st 8 h of offering. All the animals consumed more than 90% of their DMI within 12 h. Active period of rumination was observed 8h post feeding reached the peak at 16 h post feeding, then declined and animals spend considerable time idling in last 4 h of 24 h feeding cycle. Berseem supplementation showed no significant effect on eating and rumination time. It is concluded that berseem supplementation upon 30% increases the efficiency of chewing during eating and rumination, which results in increase intake and TVFA production and nutrient digestibility.

• Nuclear Engineering and Technology
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• v.27 no.4
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• pp.503-517
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• 1995

A mechanistic model for forced convective transition boiling has been developed to predict transition boiling heat flux realistically. This model is based on a postulated multi­stage boiling process occurring during the passage time of an elongated vapor blanket specified at a critical heat flux condition. Between the departure from nucleate boiling (DNB) and the departure from film boiling (DFB) points, the boiling heat transfer is established through three boiling stages, namely, the macrolayer evaporation and dryout governed by nucleate boiling in a thin liquid film and the unstable film boiling. The total heat transfer rate during the transition boiling is the sum of the heat transfer rates after the DNB weighted by the time fractions of each stage, which are defined as the ratio of each stage duration to the vapor blanket passage time. The model predictions are compared with some available experimental transition boiling data. From these comparisons, it can be seen that the transition boiling heat fluxes including the maximum heat flux and the minimum film boiling heat flux are nil predicted at low qualities/high pressures near 10 bar.

• Korean journal of food and cookery science
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• v.12 no.2
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• pp.129-137
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• 1996

The purpose of this study was that to estimate the microbial and sensory quality by the method and time of holding in the step of holding of Cow's Knee Broth, Stir-Fry Pork and Cooked Cuttlefish that were provide at the industry foodservice establishment, then to suggest safer feeding by the reasonable holding method. The results are as follows: Cow's Knee Broth: holding at room temperature was shown that the number of mi- crobiology by passage of the holding time was higer than the case of holding at steam table, but it was lower after reheating it. As a result of sensory test, it was exellent to holding at steam table and to reheat after holding room temperature within four hours and six hours each. Stir-Fry Pork: as a result of microbial analysis, in the case of holding at the steam table microbes increased safer two hours, but after four and six hours they little reduced. In the case of holding at room temperature the number of microbes increased according to the passage of time. As a result of sensory analysis, its taste of room temperature holding was fine until four and six hours each. Cooked Cuttlefish: as a microbial analysis, it was shown that the amount of total plate counts of room temperature holding ten times as high as the latter after six hours. As the result of sensory analysis, the cold holding was better until six hours and the room temperature holding was fine just until two hours. As a result of food poisoning bacteria, it was negative in every test in sample against Salmonella, Staphylococcus aureus, Vibrio parahaemolyticus.

• Clinical and Experimental Pediatrics
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• v.49 no.5
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• pp.482-488
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• 2006

Purpose : To evaluate the factors which contribute to the time of the first stool and the first urine passage. Methods : We retrospectively reviewed a chart of 1,221 infants ${\geq}34$ weeks of gestational age admitted to the normal newborn nursery of Il Sin Christian Hospital, Busan, from November 2004 to April 2005. We compared the time to first stool and urine according to maternal factors(maternal age, parity, mode of delivery, meconium-stained amniotic fluid, and maternal diabetes) and infant factors (gender, Apgar score, gestational age, type of feeding during first 24 hours, age at the first feeding, number of feeds during the first 12 hours and age at discharge). Results : In total, 95.3 percent of our infants had passed their first stool by 24 hours and 99.8 percent of them had a stool by 36 hours. A total of 95.8 percent of our infants had passed urine by 24 hours of age and 98.3 percent of them by 36 hours. Comparing preterm and term infants, the time to first urine is $6.5{\pm}5.8$ hours and $12.1{\pm}6.6$ hours, respectively(P=0.000). The time to first stool is $20.7{\pm}13.5$ hours and $10.0{\pm}6.3$ hours, respectively(P=0.000) Early-fed infants were significantly earlier in time to first urine(P=0.023) and first stool(P=0.012). There was no statistically significant relationship between the number of feeds in 0-12 hours, mode of delivery, Apgar score, parity, gender, type of feeding, maternal diabetes and the time of the first urine and first stool. Conclusion : Gestational age, birth weight and age at first feeding were significantly related to the time of the first urine and first stool passage. When there is delayed passage of the first urine and first stool, we should consider close observation of other associated symptoms and other factors previously mentioned, to avoid extensive evaluation and intervention.

• International Journal of Human Ecology
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• v.14 no.1
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• pp.29-39
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• 2013

The study examined how changes in time invested in private tutoring and academic achievement influenced each other through a multivariate latent growth model by using the data from the first to the third year presented in the KYPS. This study identifies not only how changes in the private tutoring experience exerted a direct influence on changes in academic achievement, but also measures what kind of changes in private tutoring and academic achievement had emerged over time. The detailed study results are as follows. First, the analysis of time invested in private tutoring showed that the higher the grades, the greater were the amount of time invested in private tutoring in the case of Korean language study. On the other hand, the results showed that in the case of English and mathematics, the higher the grades, the lesser was the amount of time invested in private tutoring. Second, private tutoring and academic achievement were all in a linear relationship. Third, it was shown that the time invested in private tutoring and academic achievement exerted a negative influence on each other according to the passage of time.

• Geomechanics and Engineering
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• v.16 no.2
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• pp.159-168
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• 2018

In this study, a real-time grouting management system based on the clogging theory was established to manage injection procedure in real time. This system is capable of estimating hydraulic permeability with the passage of time as the grout permeates through the ground, and therefore, capable of estimating real time injection distance and flow rate. By adopting the Controlled Injection Pressure (CoIP) model, it was feasible to predict the grout permeation status with the elapse of time by consecutively updating the hydraulic gradient and flow rate estimated from a clogging-induced alteration of pore volume. Moreover, a method to estimate the volume of the fractured gap according to the reduction in injection pressure was proposed. The validity of the proposed system was successfully established by comparing the estimated values with the measured field data.