• Korean Journal of Animal Reproduction
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• v.15 no.1
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• pp.15-22
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• 1991

To determine the preventive effects of selenium and/or vitamin E on placenta retention in Holstein dairy cows. The cows were divided six groups ; control, Se, vit.E 1x, vit.E 3x, Se + vit./E 1x and Se + vit.E 3x in Cooong Nam province. 50mg of Se as sodium selenite and 700 IU of vit. E as dl-${\alpha}$ tocopherol acetate were injected 21 day perior to expected calving date, and 700 IU vit.E was injected 3 times at 21, 14 and 7 days perior to expected calving date in vit.E 3x groups. The cows which did not expelled their placenta until 12 hours post-parturient were termed as cow of placenta retention. The i.m. injection of a single dose of selenium and vit.E has significantly(P<0.05) affected the incidence of retained placenta by 7.0% versus 25.6% of controls, but a single injection of selenium or vit.E and a combination of selenium 1x and vit.E 3x has not significantly affected. But they affected neiher subsequent reproductive performances nor milk yields.

• Journal of the Korea institute for structural maintenance and inspection
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• v.20 no.4
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• pp.44-50
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• 2016

A study to apply phase change material(PCM) to rapid hardening cement paste forming semi-rigid pavement was carried out. The characteristics fresh and hardened paste were evaluated through the experiment for a total of 6 mixtures according to the cement type and the substitution of phase change material for acrylate. The fluidity by substituting phase change material for acrylate satisfied the target flow time of 10 to 13 seconds. In case of setting time, it was possible to secure the performance of rapid hardening cement by substituting phase change material, and if the substitution ratio over 60%, the initial set occurred 1 to 2 minutes faster than other mixtures. In case of compressive strength and bond strength, it showed similar strength characteristics with the plain mixture, and it satisfied both the target compressive and bonding strength of 36MPa and 2MPa. The mixture substituting phase change material showed higher resistance to chloride ion penetration than the mixture only using acrylate and the OPC level was insufficient. From the results of physical and mechanical performances of semi-rigid pavement cement paste, the phase change material substitution rate of 20% was effective in the range of this study.

• Korean Journal of Poultry Science
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• v.30 no.2
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• pp.101-106
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• 2003

In order to study the optimum daily protein allowance for broiler breeders of 24 to 64 weeks of age on a control-fed basis, an experiment was carried out with 400 hens of Arbor Acres strain. Four levels of protein allowances were used to supply 18 to 24g of protein per day in 2g increments. As the age of hens increased, a same stepwise increase and decrease in daily energy allotment was used in all treatments. Same amount of calcium, phosphorus, methionine and lysine were supplied in all treatments and throughout laying period. Hen-day egg production was highest in hens receiving 20g protein per day(p<0.05), but there was no significant difference among those fed daily protein ranging 18 to 22g, and increasing the daily protein allotment up to 24g resulted in a significant decrease(p<0.05). Average egg weight showed a trend to increase as the daily protein allowance increase(p<0.05), but no significant difference was found among the hens fed daily protein 20 to 24g. Feed and ME conversion was superior in hens receiving 20g daily protein(p<0.05). CP conversion was increased as the daily protein allowance increase(p<0.05), but there was no significant difference between hens receiving 18 and 20g daily protein. Feed cost required per egg or per kg egg was lowest in hens fed 20g daily protein. It could be concluded that the optimum daily protein allowance was 20g in all performances.

• Korean Journal of Poultry Science
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• v.30 no.2
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• pp.73-81
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• 2003

This experiment was conducted to investigate the effects of dietary energy and protein levels on the growth rate of egg breeder pullets. A total of 360 Hy-Line Brown pullets aged 2 to 6 weeks (Phase I) were fed 5 rations differing in dietary protein (17, 19 and 20%) and energy (2,800, 2,950 and 3,050 kcal/kg, TMEn) leveIs for a period of 5 weeks and those aged 6 to 10 weeks (Phase II) were fed 5 rations differing in dietary protein (15, 16 and 17%) and energy (2,800, 2,900 and 3,000 kcal/kg, TMEn) levels in order to evaluate the optimum dietary energy and protein leveIs for egg breeder pullets reared in cages. Their body weight gains were significantly influenced by the dietary protein levels (P<0.05). The dietary energy levels did not greatly affect the growth performances throughout the experimental period. The low energy and protein regimen based on NRC requirement (control) was found to produce smaller pullets and lower tibia bone measurements as compared to the higher regimen groups. With the increase in dietary energy and protein levels, tibial bone strength and ash content also gradually increased (P<0.05). There were no significant differences in the flock uniformity among the treatments. These results indicate that increases in dietary energy and protein levels above the NRC requirements appeared to be more effective in obtaining the optimal growth and bone developments of egg breeder pullets reared in cage.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.4
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• pp.96-102
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• 2019

When GGBFS(Ground Granulated Blast Furnace Slag) with high blaine is incorporated in concrete, compressive strength in the initial period is improved, but several engineering problems arise such as heat of hydration and quality control. In this paper, compressive strength and durability performance of concrete with 3,000 Grade-low fineness slag are evaluated. Three conditions of concrete mixtures are considered considering workability, and the related durability tests are performed. Although the strength of concrete with 3,000 Grade slag is slightly lower than the OPC(Ordinary Portland Cement) concrete at the age of 28 days, but insignificant difference is observed in long-term compressive strength due to latent hydration activity. The durability performances in concrete with low fineness slag show that the resistances to carbonation and freezing/thawing action are slightly higher than those of concrete with high fineness slag, since reduced unit water content is considered in 3,000 Grade slag mixture. For the long-term age, the chloride diffusion coefficient of the 3000-grade slag mixture is reduced to 20% compared to the OPC mixture, and the excellent chloride resistance are evaluated. Compared with concrete with OPC and high fineness GGBFS, concrete with lower fineness GGBFS can keep reasonable workability and durability performance with reduced water content.

• Journal of Korea Water Resources Association
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• v.52 no.5
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• pp.337-347
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• 2019

This study proposes the framework to select the representative general circulation model (GCM) for climate change projection. The grid-based results of GCMs were transformed to all considered meteorological stations using inverse distance weighted (IDW) method and its results were compared to the observed precipitation. Six quantile mapping methods and random forest method were used to correct the bias between GCM's and the observation data. Thus, the empirical quantile which belongs to non-parameteric transformation method was selected as a best bias correction method by comparing the measures of performance indicators. Then, one of the multi-criteria decision techniques, TOPSIS (Technique for Order of Preference by Ideal Solution), was used to find the representative GCM using the performances of four GCMs after the bias correction using empirical quantile method. As a result, GISS-E2-R was the best and followed by MIROC5, CSIRO-Mk3-6-0, and CCSM4. Because these results are limited several GCMs, different results will be expected if more GCM data considered.

• Journal of Adhesion and Interface
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• v.22 no.3
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• pp.91-97
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• 2021

By introducing an organic interlayer on the Parylene C dielectric surface, the electrical device performances and the operating stabilities of organic field-effect transistors (OFETs) were improved. To achieve this goal, hexamethyldisilazane (HMDS) and octadecyltrichlorosilane (ODTS), as the organic interlayer materials, were used to control the surface energy of the Parylene C dielectrics. For the bare case used with the pristine Parylene C dielectrics, the field-effect mobility (μ_FET) and threshold voltage (V_th) of dinaphtho[2,3-b:2',3'-f ]thieno[3,2-b]- thiophene (DNTT) FET devices were measured at 0.12 cm²V^-1s^-1 and - 5.23 V, respectively. On the other hand, the OFET devices with HMDS- and ODTS-modified cases showed the improved μ_FET values of 0.32 and 0.34 cm²V^-1s^-1, respectively. More important point is that the μ_FET and V_th of the DNTT FET device with the ODTS-modified Parylene C dielectric presented the smallest changes during a repeated measurement of 1000 times, implying that it has the most stable operating stability. The results could be meaned that the organic interlayer, especially ODTS, effectively covers the Parylene C dielectric surface with alkyl chains and reduces the charge trapping at the interface region between active layer and dielectric, thereby improving the electrical operating stability.

• Journal of Digital Convergence
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• v.19 no.7
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• pp.327-340
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• 2021

The purpose of this study aims to empirically verify about the impact of the customer satisfaction on the characteristics factors(presence, empathy, responsiveness, and interaction) on the customer satisfaction of 'Asia Model Festival', which was heldis an as untacted fashion and beauty performance that was successfully conducted in Seoul duringinyear 2020. and tThe regulatory effect of innovation resistance in the relationship of the characteristic factors and the customer satisfaction was also reviewed. The analysis showed that the characteristic factors have a positive effect on customer satisfaction, and the innovation resistance is found to control the relationship between interaction, empathy, and the customer satisfaction of the characteristic factors by the subfactor. By identifying the characteristic factors that affect the customer satisfaction of the un-tacted(Zzero Ccontact) visitors, which are expanding due to COVID-19, and studying the effect of controlling the innovation resistance, this study provides a basis for knowing what un-tacted(Zzero Ccontact) visitors need and what services they want to receive, and it presents practical implications and provides basic data for relevant research.

• The Journal of the Korea Contents Association
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• v.21 no.4
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• pp.509-519
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• 2021

This study was conducted in order to acquire useful information regarding the resilience of childcare educators amidst an emergency pandemic to adjust their job stress, job burnout, and turnover intention. A questionnaire was conducted for analysis from August 19th to the 30th in 2020 and 201 responses ended up being used for analysis. The analysis results revealed that job stress, job burnout, and turnover intention of childcare educators were low while resilience was high and it was acknowledged that all of them mostly differed according to the types of personal traits. Although the job stress of childcare educators had a positive (+) influence on job burnout at a statistically significant level, it turns out that job stress does not have an influential relationship with turnover intention. Furthermore, the emotion regulation ability, impulse control, and active conductivity among resilience displayed a moderating effect in the relationship between job stress and job burnout. Amidst an emergency pandemic known as the COVID-19 virus, it has been confirmed that job stress and turnover intention of childcare educators deteriorated, and the prominent reason for this was identified as the difficulty in carrying out smooth job performances. Accordingly, measures to strengthen resilience such as countermeasures against quarantine-based job stress and turnover intent, daily management over job burnout and resilience, as well as counseling or programs based on self-focused attention have been suggested.

• The Journal of the Convergence on Culture Technology
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• v.7 no.3
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• pp.577-582
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• 2021

Recently, with the development of AR, VR, and smart device technologies, the demand for services based on non-face-to-face environments is also increasing in the fitness industry. The non-face-to-face online home training service has the advantage of not being limited by time and place compared to the existing offline service. However, there are disadvantages including the absence of exercise equipment, difficulty in measuring the amount of exercise and chekcing whether the user maintains an accurate exercise posture or not. In this study, we develop a standard exercise program that can compensate for these shortcomings and propose a new non-face-to-face home training application by using a deep learning-based body posture estimation image processing algorithm. This application allows the user to directly watch and follow the trainer of the standard exercise program video, correct the user's own posture, and perform an accurate exercise. Furthermore, if the results of this study are customized according to their purpose, it will be possible to apply them to performances, films, club activities, and conferences