• Korean Journal of Veterinary Research
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• v.44 no.2
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• pp.303-310
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• 2004

To establish a prediction table of parturition day real-time B-mode ultrasonographic examinations were performed in 12 pregnant Shih-tzu bitches. Measurement of inner chorionic cavity diameter and fetal head diameter was performed from 15 days of gestation to parturition. These were converted retrospectively based on the day of parturition (Day 0). The data of inner chorionic cavity diameter obtained from Day -44 to Day -25 and fetal head diameter obtained from Day -25 to Day -1 were used to compile a prediction table of parturition day. The 22 pregnant Shih-tzu with unknown mating time were examined to assess an accuracy of the table established in this study. And these results were applied to the prediction of parturition day and compared to actual parturition day. Parturition day prediction based on the inner chorionic cavity diameter and fetal head diameter was 100% accurate within ${\pm}2$ days. In addition, the accuracy for parturition day within 0, ${\pm}1$, and ${\pm}2$ days interval using the prediction table of parturition day were 68, 82, and 100%, respectively. Therefore, the prediction table of parturition day seems to be a useful tool for the prediction of parturition day in practice.

• KSBB Journal
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• v.6 no.4
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• pp.395-402
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• 1991

A new process was developed to degrade PVA(polyvinyl alcohol) in desize wastewater. Two symbiotic bacteria of Pseudomonas strain G5Y and PW were immobilized on the media by adsorption. A natural zeolite was chosen as the best media considering cell adhesion capacity, sedimentation rate, and material cost. PVA and COD removal efficiencies of this system for synthetic wastewater were 84% and 85% at the retention time of 6 hr, when the volumetric loading rate was PVA 8g/L·day and COD 8g/L·day, and cell density was 19,775 mg/L. In case of desire wastewater, they were 78% and 72% at the retention time of 6 hr, respectively, when the volumetric loading rate was PVA 8g/L·day and COD 13.2g/L·day, and cell density was 32,899mg/L. In case of desize wastewater, PVA and COD removal efficiencies were lower than synthetic wastewater, but cell density of the desize wastewater was lower than that of the synthetic wastewater, because there were insufficiency of necessary nutrition and variety of desize materials in the desize wastewater. A pilot test was successfully performed showing 88% and 82%, PVA and COD removal efficiencies at the retention time of 24 hr, when volumetric loading rate were 4.7 PVA g/L·day and COD 6.9g/L·day, and cell density was 12,,324 mg/L.

• Journal of Korean Society for Atmospheric Environment
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• v.8 no.1
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• pp.68-73
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• 1992

A study on the formation of particulate nitrate$(NO_3^-)$ and gaseous nitrate$(HNO_3)$ in the atmosphere was carried out in Seoul from Oct 8 to 11 1991. To collect $NO_3^-$ and $HNO_3$ in the ambient air, dual filter pack sampler (47mm$\phi$) was used. In the dual filter pack sampler, the first filter was Teflon filter (poresize 1$\mum$) for collection of $NO_3^-$ and the second filter was Nylon filter (poresize 0.45 $\mum$) for $HNO_3$. Particulate nitrate$(NO_3^-)$ and Sulfate ions were analysed by Ion chromatography. $HNO_3$ concentration was higher in the day time $(9.93\mug/m^3)$ than the night time$(3.50\mug/m^3)$, and Particulate nitrate$(NO_3^-)$ concentration was higher in the night time and early morning$(6.21\mug/m^3)$ than the day time$(4.31\mug/m^3)$. The conversion rate of $NO_x$ to total nitrate$(NO_3^-, HNO_3)$ was 7.57%/hr in the day time and 4.79%/hr in the night time, and total average conversion rate was 5.60%/hr.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.4
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• pp.466-472
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• 1997

Vegetable perilla, "Ipdlkkae 1"(Perilla frutescens var japonica Hara), was tested about the flowering and maturing responce in summer and winter. In summer season, it was researched about those responses according to the change of seeding date from May 15th to Oct. 15th at one month interval in the field. "Ipdlkkae 1" flowered Oct. 2nd under the day length of eleven hours and fourty-one minutes, compared with Sep. 6th (day length of twelve hours and fourty-three minutes) of "Yepsildlggae". And those responses showed that vegetable perilla was have to seeded before July 15th for two reason. The first is a unique response of perilla to day length. If perilla stay under short-day condition for some days, perilla will flower after four weeks. The second is a weather, especially frost and cold. In the test of latest seeding at Oct. 15th, the plants flowered more late than normal flowering period and they were not able to mature for frost of early winter. And this result showed that any other species, which has the characteristic of later flowering than that of "Ipdlkkae 1", could not able to mature in the field. In winter time, this species was tested about the same responses according to the change of short-day treatments. In the case of the test from May 1st (above fourteen hours day length), even if the test plants were stayed under short-day condition for more than 10 days, they were not able to mature, but flowerd. From the test of Apr. 15th, day length of thirteen hours, the plants were showed variable reaction to the short-day treatment. In this test, 11days for short-day treatment was a basic day to decide whether flowering was delayed or not. In the test from Apr. 1st, perilla seeds were able to harvest at least 5 days short-day treatment. In the final test from Mar. 15th, it had no need to take short-day treatment for harvesting of normal seeds, because the day length of that are twelve hours, which is an enough time to induce flowering and maturing, previously reported.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.10a
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• pp.73-76
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• 1999

In recent, concrete material like specific cement and additives having many functions hsa been developed. In road pavement, ultra high early strength cement or organic material are used to open the road early, but there are many restrictions like workable time and special equipment. We aim to developed specific concrete which 1 day strength is over 300kgf/$\textrm{cm}^2$ to open the road within one day and workable time is maintained over 1 hour that can make the concrete ready mixed concrete. In this study, we are convinced if the ratio of hauyne clinker or its additive is increased early strength property is progressed and if the ratio of non hydrous gypsum is increased longtime strength is progressed. The concrete strength is 290-310 kgf/$\textrm{cm}^2$ at 1 day, 570-640 kgf/$\textrm{cm}^2$ at 28 day and the workable time is maintained over 30 minutes. As the results of this experiments We find out the possibility to developed the 1 day usable ready mixed concrete with high early strength.

• Journal of the Korean Association of Geographic Information Studies
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• v.26 no.4
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• pp.40-55
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• 2023

Arbor Day is a day that encourages people to plant trees and symbolizes the timing of planting. Arbor Day has been honored on April 5th in Korea, but it often does not agree to actual planting time due to global warming. This study confirmed the discrepancy between Arbor Day and regional soil-thawing times and reviewed alternative dates for tree planting using satellite-based soil-thaw data (FT-ESDR) from 1991 to 2020. Study results showed that the start time of planting on the Korean Peninsula, which was indicated by soil-thaw dates, was March 24 during 1991-2000, and it progressively changed to March 17 during 2011-2020. Should Arbor Day be changed based on soil-thaw periods, mid-March would be the most comprehensive, suitable alternative period considering the number of governmental administration units (cities and counties) and the land area of soil-thaw. Tree-Planting Day (March 14) and International Day of Forests (March 21) were found suitable for alternative dates to Arbor Day because they were close to the average soil-thaw time of Korean Peninsula (March 19) and land area whose soil-thaw time was within 10 days from those two dates ranged from 52.5% to 58.8% centered geographically on the mid-section of the peninsula. Since the periods of soil-thaw will continue to change due to climate change, it is necessary to reflect the trend of advancing planting periods in the future if Arbor Day is changed to an earlier date.

• Safety and Health at Work
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• v.10 no.3
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• pp.254-259
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• 2019

Background: This cross-sectional study assessed the sleep quality using the ActiGraph and investigated the relationship between the parameters of sleep assessment and the type of shift work in Korean firefighters. Methods: The participants were 359 firefighters: 65 day workers (control group) and 294 shift workers (shift work group: 77 firefighters with 3-day shift, 72 firefighters with 6-day shift, 65 firefighters with 9-day shift, and 80 firefighters with 21-day shift). Sleep assessments were performed using the ActiGraph (wGT3X-BT) for 24 hours during day shift (control and shift work group) and night shift and rest day (shift work group). The participants recorded bed time and sleep hours during the measurement period. Results: Sleep efficiency, total sleep time, and percentage of wake after sleep onset during night work were lower in the shift work group than control group (p < 0.05). Sleep efficiency decreased in night shift and increased in rest day, whereas wake after sleep onset increased in night shift and decreased in rest day (p < 0.05). Among shift work groups, sleep efficiency of 6-day shift was higher in day shift, and sleep efficiency of 21-day shift was lower in night shift than other shift groups (p < 0.05). Conclusion: We found that the sleep quality in night shift of the shift work group was poorer than the control group. As to the type of shift work, sleep quality was good in 6-day shift and poor in 21-day shift. Thus, fast rotating shift such as 6-day shift may be recommended to improve the sleep quality of the firefighters.

• Korean Journal of Veterinary Service
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• v.23 no.2
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• pp.143-152
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• 2000

Sulfamethazine sodium was orally administrated to sprague-dawley strain male rats(body weight, 200-300g) with using sonde at the rate of 20 mg/100g body weight(recommended therapeutic dose) on once a day for 3 days. There were investigated the depletion rate of the sulfamethazine in serum, liver and skeletal muscle of rat at the time 8 hours, 1st, 2nd, 3rd, 4th, 5th and 6th day after administration sulfamethazine sodium. 1. The mean concentrations of sulfamethazine in serum according to the time lapsed after oral administration of the sulfamethazine soudijm were showed 215.53$\pm$42.99 ppm at the 8 hours after withdrawal of medicated sulfamethazine. And gradually according to the time lapsed, the concentrations of sulfamethazine residues in serum were significantly (p<.05) decreased 25.87$\pm$5.18 ppm at 1st day, 2.30$\pm$0.61 ppm at 3rd day and 0.11$\pm$0.02 ppm at 6th day after withdrawal of medicated sulfamethazine. 2. The mean concentrations of sulfamethazine in liver were significantly (p<.05) decreased 81.77 $\pm$ 12.88 ppm to 0.11$\pm$0.03 ppm between 8 hours and 6th day according to the time lapsed after oral administration of the sulfamethazine sodium for 3 days. 3. After oral administration of the sulfamethazine sodium, the mean concentrations of sulfamethazine in skeletal muscle were significantly (p<.05) decreased 35.96$\pm$1.39 ppm to 0.009$\pm$0.001 ppm between 8 hours and 6th day after withdrawal of medicated sulfamethazine. At the 4th day, the concentrations of sulfamethazine residues were showed 0.10 $\pm$ 0.04 ppm below 0.1 ppm at the permitted limit concentration of muscle in Korea. 4. After oral administration of the sulfamethazine sodium once a day for 3 days, there were showed the highest concentration in serum (215.53$\pm$42.99 ppm) than in liver(81.77$\pm$12.88 ppm) and skeletal muscle (35.96$\pm$1.39 ppm) at the 8 hours after withdrawal of medicated sulfamethazine. The mean concentration of sulfamethazine residues in serum, liver and skeletal muscle were gradually decreased according to the time lapsed.

• Journal of the Korean Society of Food Culture
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• v.24 no.3
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• pp.256-266
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• 2009

The purpose of this study was to determine conditions of dining behaviors, sleep patterns, rates of obesity and intake of snacks and self-purchased snacks deriving from the lack of sleep in academic high school students. The anthropometric characteristics, height and weight (p<0.05), and the distribution of obesity index (p<0.001) showed significant differences between males and females. Dining scores for both male and female students decreased as the frequency of day time napping increased. Although, there was no significant difference in obesity-related "lack of sleep" between males and females, the rate of "being overweight" was slightly higher in female students who indicated that they experienced a "lack of sleep" than female students that indicated "no lack of sleep". While, whether intake of snacks and self-purchased snacks or not, day time napping frequency affected not to male students. However, the frequency of day time napping among females who ate snacks one or more times a day was higher (p<0.05), and a greater frequency of eating self-purchased snacks correlated with a greater frequency of day napping (p<0.01). Consequently, lack of sleep was identified as one of the factors increasing the frequency of intake of snacks and self-purchased snacks in females. Thus, this study suggests that dining behavior guidance should be given along with systematic and continual nutrition education so that the intake of snacks and self-purchased snacks can be moderated to optimize the physical and mental growth and development of adolescents.

• Journal of Korean Society on Water Environment
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• v.20 no.4
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• pp.321-326
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• 2004

The objective of this study is to test the applicability of neural network models to forecast water quality at Naesa and Pyongchang river. Water quality data devided into rainy day and non-rainy day to find characteristics of them. The mean and maximum data of rainy day show higher than those of non-rainy day. And discharge correlate with TOC at Pyongchang river. Neural network model is trained to the correlation of discharge with water quality. As a result, it is convinced that the proposed neural network model can apply to the analysis of real time water quality monitoring.