• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.1
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• pp.52-58
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• 2015

White ledger usually includes white office paper, computer paper, and copy machine paper. Because these grades need high optical properties, fluorescent whitening agents (FWAs) are widely used in the papermaking process. FWAs are the most powerful and effective chemical used to obtain high CIE whiteness and ISO brightness in papers. The rising demand for white or ultra-white papers has increased the use of FWAs. However, FWAs used in white ledger can restrict its use, even though white ledger is widely used as a raw material in paperboard mills. Therefore, it is necessary to develop methods to control FWAs from white ledger to increase its use in paperboard mills. In this study, the behaviors of disulpho fluorescent whitening agent (D-FWA), tetrasulpo fluorescent whitening agent (T-FWA), and hexasulpho fluorescent whitening agent (H-FWA) during the recycling process were identified as a first step to remove FWAs from white ledger. We prepared four types of papers (dyed with D-FWA, T-FWA, and H-FWA), disintegrated these papers, and made handsheets. This recycling process was carried out three times in a laboratory. After each round of recycling, the hand-sheets' CIE whiteness and fluorescence index were measured, and the distribution of FWAs in the Z-direction was observed using CLSM images. FWA reductions in the model papers were calculated using fluorescence indices as a function of the number of recycling. FWAs in handsheets containing T-FWA and H-FWA decreased linearly as a function of the number of recycling, but D-FWA did not show a significant reduction in the fluorescence index after recycling. T-FWA and H-FWA showed similar distributions of D-FWA after recycling. Therefore, as much T-FWA and H-FWA as possible must be detached in the early processes of papermaking at paperboard mills.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.37 no.3
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• pp.585-592
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• 2017

Most sewer lines buried in the city are likely to be collapsed due to serious aging. Also, due to the high concentration of development and high population density and traffic, the collapse of the sewer will cause enormous social and economic damage. Therefore, proactive maintenance is required to prevent accidents caused by deteriorated sewer pipe. In order to utilize limited budget effectively, risk-based prioritization methods should be proposed that simultaneously consider the consequence of failure and the probability of failure. In this study, the method of risk-based prioritization of sewer was examined by reviewing various cases of overseas studies and applied to the urban sub-catchment. First, the impact factors that can be secured through the sewer GIS DB in Seoul were derived, and the weight, sub-criteria, and impact score of each impact factor were determined and the consequence of failure was calculated by weight sum method. In addition, the probability of failure was calculated by dividing the service life by the estimated useful life, and the consequence of failure and the probability of failure were classified into five grades by the Jenks natural breaks classification method. The prioritization method was applied to sub-catchment in the Seoul to derive a risk matrix and a risk grade. As a result, 26% of all subjects were selected as the inspection priority subjects with 4-5 risk grade. Therefore, using the risk-based CCTV prioritization methodology, it will be possible to systematically determine the objects that need investigation first.

• Analytical Science and Technology
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• v.31 no.3
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• pp.122-133
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• 2018

In this study, groundwater quality data measured for 11 years from 2006 to 2016 were analyzed statistically for 101 civil defense emergency water supply facilities (CDEWSF) in the Gwangju area. The contamination level was quantified into four grades by using excess drinking water quality standards, average concentration analysis, and tendency analysis results for each facility. On the basis of this approach, the groundwater contamination degree of each item was evaluated according to land use status, installation year, depth, and geological distribution. The contamination grade ratios, which were obtained by analyzing three contamination indicators (water quality exceeded frequency, average concentration analysis, and trend analysis) for 15 items on statistically significant of civil defense emergency water was relatively high, in the order of Turbidity (51.5 %) > Color (32.7 %) > Nitrate nitrogen (28.7 %) > Hardness (25.7 %). As a result of the contamination grade analysis, except for the items of Turbidity, Color, and Nitrate nitrogen, the contamination levels were distributed in various degrees from "clean (0)" to "seriously contaminated (3)." Regarding the contamination grade of 12 items, 25 % of the total were classified as "possibly contaminated (1)," and 75 % were rated "clean (0)." The four items (Turbidity, Color, Nitrate nitrogen, and Hardness) for which contamination indication rate were evaluated as "high" by the were visualized on a contamination map.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.18 no.2
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• pp.130-137
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• 2007

Objectives: Studies investigating problematic internet use have increased rapidly and have been focused on its causes, psychopathology, prevalence, characteristics and so on. However, there are few studies concerning the correlation between problematic internet use and youth health risk behavior. Therefore, the purpose of this study was to examine the relationship between problematic internet use and youth health risk behavior. Methods: A community sample of 632 high school students in grades 10 and 11 was collected for the survey. The sample was assessed using the Youth Risk Behavior Surveillance System(YRBSS) and Young's Diagnostic Questionnaire of Internet Addiction(YDQ). The subjects were classified into two groups: normal and problematic internet use, and the problematic internet use group was further divided into at-risk use and addiction groups. Results: There were 56 subjects(8.9%) in the internet addiction group and 56 subjects(8.9%) in the at-risk internet use group. The other 507 subjects were classified as normal. The subjects in the internet addiction group kissed more frequently and ate less fruit than those in the normal group. They also showed a relatively higher tendency to watch TV, ride in a car driven by a drunk driver and to carry a weapon than those in the normal group. There were no differences in health risk behaviors between the subjects in the internet addiction group and those in the at-risk internet use group, except for the possibility of riding in a car driven by a drunk driver. Conclusion: Unlike the normal group, there was very little difference in health risk behavior between the internet addiction group and the at-risk internet use group, which indicates that the addiction group and the at-risk internet use groups are homogenous. It is important to focus on the behavior of individuals in the at-risk group, and preventive measures should be taken in order to reduce the possibility of at-risk adolescents becoming addicted.

• Journal of The Korean Association For Science Education
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• v.39 no.6
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• pp.767-775
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• 2019

This study was conducted to analyze explicit and implicit teaching cases of scientific terms in accordance with the 2015 revised curriculum, pointing out the problems of current textbooks in terms of scientific terms education and proposing method to improve them. Scientific terms used in eight science textbooks of 2015 revised curriculum, third and sixth graders of elementary school, first graders of middle school and first graders of high school were extracted, and cases used explicitly and implicitly were collected and analyzed. Brief summary of the results of the study is as follows. First, scientific terms were used in elementary, middle, and high school science textbooks at a rate of about 15 to 30 percent of the total vocabulary contained in the textbooks, which is on average more than five times larger than those in foreign countries based on the number of scientific terms included on each page. Second, among the scientific terms used in science textbooks, the percentage of scientific terms in which semantic education is achieved through explicit means was 9.7 to 18.8 percent, which naturally means that the remaining 80 percent or more of the scientific terms are presented in the form of implicit education. Third, even though the ratio of explicit term education should be higher in the lower grades, the ratio of explicit term education in elementary schools was lower than 10% in the sixth grade.

• The KIPS Transactions:PartC
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• v.11C no.6 s.95
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• pp.773-780
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• 2004

In this paper, we measured the transmission characteristics of a MPEG2 and a DV that are typical stream-type traffics on the very high speed network and carried out the subjective evaluation of end users for these stream-types. In the subjective evaluation of these stream-type data, video quality evaluation is based on ITU-R BT.500-1 and audio qualify evaluation is based on ITU-R BS.1116-1. Also experiment method to acquire the subjective evaluation of end users is selected the 5 grades method of DSCQS. Under the same condition, in case of MPEG2, the evaluation grade of the video and the audio duality becomes deteriorated at the load rate of $54\%$ that network traffic increases rapidly. In case of DV the evaluation grade of video duality began decrease, but the degree of the change was slower than MPEG2 at the same load rate. Moreover the subjective evaluation grade of end users was superior to load rate $70\%$ in case of DV audio quality, traffic and QoS control that consider the subjective evaluation of end user is required. Conclusively, in case of MPEG2, we can perform traffic control that only use the actual measurement values on the network. However in case of DV, we can perform traffic control that the actual measurement values on the network and the subjective evaluation of end users are considered at the same time.

• Korean Journal of Social Welfare
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• v.68 no.2
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• pp.213-232
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• 2016

The purpose of this study is to explore the stress profile that adolescent perceives by using Latent Profile Analysis (LPA), and to examine the effect of characteristics variable per groups that appeared in profile. By using the cross-section data of 'A survey on the human right of Korean children and adolescent in 2013' issued by National Youth Policy Institute, the LPA concerning the stress type was conducted and surveyed 9,521 adolescents from fourth grade in elementary school to seniors in high school nationwide. The result of this study shows that two class types were selected according to the goodness-of-fit index and latent class classification rate. Type 1 is named low-risk group as they show low level, whereas type 2 is named relative risk group as they show high level. In order to predict the characteristics of adolescent stress, the study conducted Binary Logistic Regression analysis on the basis of low-risk group. There is higher probability to belong to relative risk group, the more they are female students than male students, the less their subjective health condition and happiness, the more runaway experience, the less school grades and the less economic affluence in their household. The implication of this research, its limitation and direction of follow-up research were suggested.

• Journal of Korean Home Economics Education Association
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• v.24 no.3
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• pp.1-34
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• 2012

The objectives of this study are to introduce a critical perspective of the multicultural education in home economics education, to develop teaching-learning materials and to apply them in classes for the purpose of enhancing students' multicultural competence for a validity test. For these purposes, family life culture sections from six high school technology and home economics textbooks were analyzed based on the contents and elements of multicultural competence. After recomposing the family life culture sections, this study developed 12-session teaching-learning materials with an emphasis on media literacy. Among them, 4-session plans were taught in classrooms for 247 students in the 10th grades. To test the validity of the plans, a questionnaires was given to the students as a pre- and post-test. The data were analyzed with paired t-tests. The results showed significant pre and post differences in all sections of multicultural competence except the section of 'general cultural understanding'. This implied that the developed teaching-learning materials were effective in helping students overcome ethnocentrism and enhance the understanding of cultural differences.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.10
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• pp.1656-1665
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• 2020

Objective: This study aimed to determine the effects of stress during slaughter of beef cattle on physiological parameters, carcass, and meat quality at a Federal Inspection Type slaughterhouse located in the southeast of Mexico. Methods: A total of 448 carcasses of male Zebu×European steers with an average age of 36 months were included. Carcass assessment of presence of bruises and bruise characteristics was carried out on each half-carcass. Blood variable indicators of stress (packed cell volume, neutrophil to lymphocyte ratio, glucose, cortisol concentration) and meat quality parameters (pH, color, shear force, drip loss) were evaluated. Results: Of the 448 carcasses evaluated, 81% of the carcasses showed at least one bruise; one bruise was detected in 36.6% and two bruises in 27.0% of animals. Of the 775 bruises found, 69.2% of the bruises were grade 1 in region 3. Of the 448 carcasses studied, 69.6% showed hyperglycemia (6.91 mmol/L); 44.3% and 22.7% showed high (74.7 ng/mL) and extremely high (108.8 ng/mL) cortisol levels, respectively, indicative of inadequate handling of animals during preslaughter and slaughter. Of the carcasses evaluated, 90.4% had a pH ≥5.8 with an average of pH 6.3. In both pH groups, meat samples showed L^⋆ values >37.0 (81.6%) and a shear force >54.3 N; meat pH≥5.8 group showed a drip loss of 2.5%. These findings were indicative of dark, firm, and dry (DFD) meat. According to principal component analysis, grades 1 and 2 bruises in region 3 and grade 1 bruises in region 5 were highly associated with cortisol, drip loss, and color parameters b^⋆ and h^⋆ and were negatively associated with L^⋆, a^⋆, and C^⋆. Conclusion: The bruises probably caused by stress-inducing situations triggered DFD meat. Appropriate changes in handling routines in operating conditions should be made to minimize stress to animals during the slaughter process to improve animal welfare and meat quality.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.14
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• pp.5957-5961
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• 2015

Background: We designed this randomized controlled trial (RCT) to assess whether lobaplatin-based concurrent chemotherapy might be superior to cisplatin-based concurrent chemotherapy for FIGO stage II and III cervical cancer in terms of efficacy and safety. Materials and Methods: This prospective, open-label RCT aims to enroll 180 patients with FIGO stage II and III cervical cancer, randomly allocated to one of the three treatment groups (cisplatin $15mg/m^2$, cisplatin $20mg/m^2$ and lobaplatin $35mg/m^2$), with 60 patients in each group. All patients will receive external beam irradiation (EBRT) and high-dose-rate intracavitary brachytherapy (HDR-ICBT). Patients in cisplatin $15mg/m^2$ and $20mg/m^2$ groups will be administered four cycles of $15mg/m^2$ or $20mg/m^2$ cisplatin intravenously once weekly from the second week to the fifth week during EBRT, while patients inthe lobaplatin $35mg/m^2$ group will be administered two cycles of $35mg/m^2$ lobaplatin intravenously in the second and fifth week respectively during pelvic EBRT. All participants will be followed up for at least 12 months. Complete remission rate and progression-free survival (PFS) will be the primary endpoints. Overall survival (OS), incidence of adverse events (AEs), and quality of life will be the secondary endpoints. Results: Between March 2013 and March 2014, a total of 61 patients with FIGO stage II and III cervical cancer were randomly assigned to cisplatin $15mg/m^2$ group (n=21), cisplatin $20mg/m^2$ group (n=21) and lobaplatin $35mg/m^2$ group (n=19). We conducted a preliminary analysis of the results. Similar rates of complete remission and grades 3-4 gastrointestinal reactions were observed for the three treatment groups (P=0.801 and 0.793, respectively). Grade 3-4 hematologic toxicity was more frequent in the lobaplatin group than the cisplatin group. Conclusions: This proposed study will be the first RCT to evaluate whether lobaplatin-based chemoraiotherapy will have beneficial effects, compared with cisplatin-based chemoradiotherapy, on complete remission rate, PFS, OS, AEs and quality of life for FIGO stage II and III cervical cancer.