• The Bulletin of The Korean Astronomical Society
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• v.35 no.2
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• pp.53.2-53.2
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• 2010

A Jupiter-family comet, 17P/Holmes, suddenly underwent a spectacular outburst on 2007 October 23, about 173 days after the perihelion passage. There has been no more outstanding comet outburst than the 17P/Holmes event since the beginning of modern astronomical observations. However, little is known about the activity of the comet before the outburst because of the accidental event. We found that 17P/Holmes appeared in the AKARI all sky survey data. It was taken on 2007 August 23, 112 days after the perihelion passage and 61 days before the outburst. The 9 micron images shows obvious coma and tail. We study the dust production rate from these images and evaluate the fractional active area. We compare these results with those of data after the outburst, and discuss the aftermass.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.23 no.7
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• pp.566-570
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• 2010

Electro-optic modulators based on 25 monolayer langmuir-blodgett films of vinylidene fluoride and trifluoroethylene, P(VDF-TrFE), were fabricated. The LB films were prepared by transferring the monolayers on to an ITO coated glass with a surface pressure of 5 dyne/cm by use of the langmuir-schaefer deposition method. Measurement of the electro-optic coefficient has been carried out using a simple reflection techique. The E/O coefficient was found to be 154.9 pm/V and that value remained stable for at least 50 days.

• Food Science of Animal Resources
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• v.39 no.3
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• pp.410-417
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• 2019

The aim of this study is to evaluate the incidence of white striping abnormality and its consequences on the quality traits of raw and processed turkey breast (chemical composition, color traits, and water holding capacity). In total, about 2300 breasts from 22 flocks were used to assess the incidence and 60 breasts to evaluate the quality traits. Our study showed that the total incidence of moderate and severe white striping was 61.3% out of them, moderate cases were 49.4%. Severe white striped turkey breast exhibited significantly lower protein content (21.1 vs. 23.2 and 23.16%, p<0.05) and higher fat content (2.3 vs. 0.77 and 1.76%, p<0.05) if compared to normal and moderate white striped breast respectively. Moreover, moderate and severe white striped meat showed significantly higher redness (a*) (2.98 and 3.14 vs. 1.48, p<0.05) and yellowness (b*) indexes (7.27 and 7.95 vs. 4.05, p<0.05) than normal meat, respectively.

• KSBB Journal
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• v.15 no.6
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• pp.548-555
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• 2000

A hydrogel, poly(N-isopropylacrylamide-co-N, N-dimethylaminopropylmethacrylamide), sensitive to both pH and temperature, was synthesized and characterized at $^13∼23{\circ}C$ and pH of 10.3∼12.3. The gel was more transparent and mechanically stronger at lower preparation temperature and pH. Large pores observed in scanning electron microscope seem to be responsible for the lower biomolecular separation efficiency. The lower critical solution temperature (LCST) decreased at a higher polymerization temperature. At $25^{\circ}C$, which is lower than the LCST, the gel was swollen regardless of the solution pH. At $40^{\circ}C$, however, the gel was swollen at neutral and acidic pHs even though the temperature was higher than the LCST. The gel collapse pH, defined as the point at which the gel made its largest volume decrease per unit pH increment, increased as the gel preparation temperature increased.

• Resources Recycling
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• v.25 no.6
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• pp.23-28
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• 2016

In this study, leaching process to extract phosphorus from the steelmaking slag was investigated for using the fertilizer resources of agriculture. In general, the phosphorus of steelmaking slag is formed as $C_2S-C_3P$ solid solution, and also, this solid solution is soluble in water more than the other phase in slag, and less than free CaO phase. In the present experiment, the influence of pH on the leaching behavior of various elements from the steelmaking slag was investigated by using multi-component steelmaking slag. When the pH was decreased, the concentration of Ca, Si, P and Fe in solution from the steelmaking slag was increased. Furthermore, at a pH of 3, the concentration of P ion in solution was decreased as leaching time increased. It is considered that the decrement of P was caused from the precipitation reaction between P ion and Fe ion in solution.

• Research in Community and Public Health Nursing
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• v.15 no.2
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• pp.277-288
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• 2004

Purpose: This study was to provide basic information for preventing high school students from smoking by examining their actual smoking condition and their knowledge and attitude about smoking. Method: The subjects were 515 students selected from six(6), high schools in Jecheon. Data were collected using a questionnaire from the 1st to the 17th of December 2002. The author prepared the tool by modifying the scale of knowledge and attitude about smoking developed by Moon(2001). Data were analyzed with SPSS/WIN program using frequencies, percentages, $x^2$-test, t-test, ANOVA. Duncan test and Pearson's correlation coefficient. Result: 1. The percentage of ex-smoking students was 29.9% of male students and 18.6% of female ones. The percentage of currently smoking students was 23.9% of male students and 3.0% of female ones. The percentage of non-smoking students was 46.2% of male students and 78.4% of female ones, 2. There were not significant differences in smoking knowledge according to smoking status in male and female students. 3. There were significant differences in smoking attitude according to smoking status in male(F=32.70, p=.000) and female(F=11.15, p=.000) students. 4. In smoking status according to general characteristics, there were significant differences according to the type of school($x^2$=32.93, p=.000), grade($x^2$=11.91, p=.018), educational level of the father($x^2$=30.52, p=.000) and the mother($x^2$=14.23, p=.027), monthly allowance($x^2$=17.19, p=.028), harmony of family members($x^2$=15.23, p=.019), school life($x^2$=26.96, p=.00l) and school record($x^2$=30.24, p=.000). 5. In smoking status according to smoking-related characteristics, there were significant differences according to experience in cigarette purchase($x^2$=150.04. p=.000), experience in errands for cigarette($x^2$=20.00, p=.000), knowledge of cigarette price($x^2$=72.52, p=.000), close friends' smoking($x^2$=107.41. p=.000) and smoking of brothers and sisters($x^2$=16.97, p=.002). 6. There were significant correlation between knowledge and attitude about smoking in the whole students(r=.337. p=.000), ex-smokers(r=.324. p=.000), non-smokers(r=.369. p=.000) but there was not a significant correlation between knowledge and attitude about smoking in current smokers(r=.128. p=.30l). Conclusion: Smoking prevention education should considered students' smoking status. Current smokers need smoking prevention education aiming to change their attitude toward smoking in order for them to reduce smoking and to practice smoking cessation.

• Journal of Gastric Cancer
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• v.23 no.3
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• pp.428-450
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• 2023

This meta-analysis examined the surgical management of older patients (>80 years) with gastric cancer, who were often excluded from randomized controlled trials. We analyzed 23 retrospective cohort studies involving 18,372 patients and found that older patients had a higher in-hospital mortality rate (relative risk [RR], 3.23; 95% confidence interval [CI], 1.46-7.17; P<0.01) and more post-operative complications (RR, 1.36; 95% CI, 1.19-1.56; P<0.01) than did younger patients. However, the surgical complications were similar between the two groups. Older patients were more likely to undergo less extensive lymph node dissection and longer hospital stays. Although older patients had statistically significant post-operative medical complications, they were not deprived of surgery for gastric cancer. The comorbidities and potential risks of post-operative complications should be carefully evaluated in older patients, highlighting the importance of careful patient selection. Overall, this meta-analysis provides recommendations for the surgical management of older patients with gastric cancer. Careful patient selection and evaluation of comorbidities should be performed to minimize the risk of post-operative complications in older patients, while recognizing that they should not be deprived of surgery for gastric cancer.

• Journal of the Korean Geotechnical Society
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• v.23 no.8
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• pp.97-106
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• 2007

In this study, experiments are conducted to find out the effect of waste leachate on landfill clay liner system. Tensile test, hydrometer analysis and crack pattern test were conducted on sand-bentonite mixtures with different pH values of water. The tensile strength of specimen compacted with pH 9 of water is smaller than that of specimen compacted with for pH 3 and 6 of water. That is, the higher the pH value, the smaller the tensile strength, because a higher pH solution decreases flocculation phenomenon. The percent finer also increased with high pH value in particle size distribution of fine grained soil (<0.075 mm), because the velocity of particles settling decreases. This trend becomes the clearer as the content of bentonite, becomes the larger, because the higher pH value decreases flocculation structure of fine soils. The results of the crack pattern tests also showed the effect of pH values of water.

• Child Health Nursing Research
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• v.23 no.2
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• pp.199-206
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• 2017

Purpose: The purpose of this study was to explore perception of the clinical learning environment, resilience and perfectionism in relation to practice burnout and to identify factors influencing practice burnout in student nurses. Methods: A descriptive correlational study was conducted. The participants were 313 student nurses from three universities in B and U city. Data were analyzed using t-test, ANOVA, Pearson correlation coefficient, $Scheff{\acute{e}}s$ test and multiple regression analysis. Results: Mean score for practice burnout in student nurses was 2.92 out of 5 points. Practice burnout explained 44.7% of the variance in perfectionism (${\beta}=.245$, p<.001), satisfaction with college life (${\beta}=.232$, p<.001), resilience (${\beta}=-.228$, p<.001), clinical learning environment (${\beta}=-.193$, p<.001), satisfaction with major (${\beta}=.180$, p=.001), practical relationships with peers (${\beta}=.128$, p=.005), and satisfaction with clinical practice (${\beta}=.124$, p=.039). Conclusion: Research results suggest that the important variable for student nurses' practice burnout is perfectionism. Therefore education is needed to develop strategies to manage perfectionism and reduce practice burnout.

• Quality Improvement in Health Care
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• v.23 no.2
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• pp.57-66
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• 2017

Purpose:The purpose of this study was to identify the patient's characteristics influencing patient's comprehensibleness of doctor's explanation. Methods: This study was conducted as a secondary data analysis using the raw data of The 6th Korea National Health and Nutrition Examination Survey (KNHANES VI) conducted in 2015. The survey sampled 22,948 adults, and 4,469 of them were included in this analysis. Multiple regression analysis was performed to determine the patient's characteristics influencing patient's comprehensibleness of doctor's explanation. Results: The patient's comprehensibleness of doctor's explanation were more higher as age (t=5.65, p<.001), female (t=4.40, p<.001), subjective good health status (t=3.48, p=.001) were higher. On the other hand, the patient's comprehensibleness of doctor's explanation were more higher education level (t=-6.80, p<.001), not-recent outpatient experience (t=-6.04, p<.001), pain/discomfort (t=-2.64, p=.008), anxiety/depression (t=-2.58, p=.010) were lower. Conclusion:It is necessary to be provided the patients who are higher education level, pain/discomfort and anxiety/depression with applying the doctor's detailed explanation and intervention programs.