• Journal of the Korean Recycled Construction Resources Institute
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• v.7 no.1
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• pp.37-43
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• 2019

This research studied production of lightweight filling production for sink hole restoration utilizing various industrial by-products(2kinds of fly ash, petro-cokes CFBC ash, blast furnace slag fine particle). For this purpose, the mixed raw material properties(compressive strength) behaviors according to the blending ratio of industrial by-products were examined by applying the experimental design method and statistical analysis was performed using the commercial program MINITAB. Compressive strengths of industrial by-products were strongly dependent on blast furnace slag powder. Compressive strength(3days aging) was 3~11MPa depending on the amount of blast furnace slag powder used. The use of CFBC fly ash was evaluated to have the least effect on compressive strength. In addition, the compressive strength and the coefficient of permeability were measured by preparing foamed concrete for the experimental batch 1 condition in the mixture experimental design. In this case, the bulk density is 0.9 to 1.0, the apparent porosity is 30 to 50%, the compressive strength(3days old) is 1 to 2MPa, and the permeability coefficient is $10^{-2}$ to $10^{-3}cm/sec$.

• The Korean Journal of Applied Statistics
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• v.32 no.1
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• pp.161-171
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• 2019

Varied methods have been researched continuously because the past as the daily maximum electricity demand expectation has been a crucial task in the nation's electrical supply and demand. Forecasting the daily peak electricity demand accurately can prepare the daily operating program about the generating unit, and contribute the reduction of the consumption of the unnecessary energy source through efficient operating facilities. This method also has the advantage that can prepare anticipatively in the reserve margin reduced problem due to the power consumption superabundant by heating and air conditioning that can estimate the daily peak load. This paper researched a model that can forecast the next day's daily peak load when considering the influence of temperature and weekday, weekend, and holidays in the Seasonal ARIMA, TBATS, Seasonal Reg-ARIMA, and NNETAR model. The results of the forecasting performance test on the model of this paper for a Seasonal Reg-ARIMA model and NNETAR model that can consider the day of the week, and temperature showed better forecasting performance than a model that cannot consider these factors. The forecasting performance of the NNETAR model that utilized the artificial neural network was most outstanding.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.7
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• pp.68-77
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• 2019

The purpose of this study was to determine the relevance and different factors having an impact on sexual assertiveness and sex stereotypes for the attitude among nursing students toward homosexuality. A survey was conducted on 253 nursing students in D city using a self-report questionnaire. The data was collected from April 11 to April 20, 2019 and it was then analyzed by descriptive statistics, t-tests, ANOVA, Pearson's correlations and multiple regression using SPSS 22.0. The average of sexual assertiveness in the nursing students was $4.44{\pm}0.37$, and the average of sex stereotypes was $2.08{\pm}0.58$, and the average of attitude toward homosexuality was $2.75{\pm}0.37$. The attitude toward homosexuality according to the general characteristics differed among religions (F=13.32, p<.000), religious life (F=20.43, p<.000) and method of parenting (F=2.74, p<.044). There was a statistically significant negative correlation between sexual assertiveness and the attitude toward homosexuality (r=-0.13, p=.034). Also, there was a statistically significant positive correlation between sex stereotypes and the attitude toward homosexuality (r=0.24, p<.000). Religion, religious life and sex stereotypes were the influential factors. Models that included the variables explained 23.1% of the variance for the attitude toward homosexuality. Thus, it is necessary to create an interventional strategy related to nursing student' attitude towards homosexuality so as to develop a practical educational program for promoting healthy gender identity.

• Journal of the Society of Disaster Information
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• v.14 no.4
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• pp.480-491
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• 2018

Purpose : This study aims to suggest social support composed of organizational support and managerial support would be systematically managed to enhance Disaster Operations Management at Seoul Emergency Operations Center. Method : Emotional labor was used as an independent variable, and organizational commitment was used as a dependent variable to analyze the mediating effects of social support. Results : First, in the aspect of organizational support, the objective evaluation of disaster situation management, disaster situation management emotional labor reduction education and training program development, monitoring of disaster situation management, quality improvement and work imbalance mitigation of firefighters, and emergency coordination managers are needed for systematic work management for emotional labor settlement. Secondly, it is necessary to select competent firefighters in the level of managerial support, to prepare healing measures for structured phased emotional labor for firefighters, and to have counseling competency for managers for emotional labor firefighting officers. Conclusion : In order to improve disaster management ability, education and training programs should be developed to improve organizational commitment based on social support.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.17 no.1
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• pp.107-120
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• 2019

The decommissioning of one nuclear power plant in a multi-unit nuclear power plant (multi-unit NPP) site may pose radiation exposure risk to decommissioning workers. Thus, it is essentially required to evaluate the exposure dose of decommissioning workers of operating multi-unit NPPs nearby. The ENDOS program is a dose evaluation code developed by the Korea Atomic Energy Research Institute (KAERI). As two sub-programs of ENDOS, ENDOS-ATM to anticipate atmospheric transport and ENDOS-G to calculate exposure dose by gaseous radioactive effluents are used in this study. As a result, the annual maximum individual dose for decommissioning workers is estimated to be $2.31{\times}10^{-3}mSv{\cdot}y^{-1}$, which is insignificant compared with the effective dose limit of $1mSv{\cdot}y^{-1}$ for the public. Although it is revealed that the exposure dose of operating multi-unit NPPs does not result in a significant impact on decommissioning workers, closer examination of the effect of additional exposure due to actual demolition work is required. The calculation method of this study is expected to be utilized in the future for planned decommissioning projects in Korea. Because domestic NPPs are located in multi-unit sites, similar situations may occur.

• Journal of Korea Society of Industrial Information Systems
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• v.24 no.2
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• pp.33-40
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• 2019

Many companies have tried to develop wind power generators with a larger capacity, smaller size and lighter weight. High temperature superconducting (HTS) generators are more suitable for wind power systems because they can reduce volume and weight compared with conventional generators. However, the HTS generator has problems such as huge vacuum vessel and the difficulty of repairing the HTS field coils. These problems can be overcome through the modularization of the HTS field coil. The HTS module coil require a current leads (CLs) for deliver DC current, which causes a large heat transfer load. Therefore, CLs should be designed optimally for reducing the conduction and Joule heat loads. This paper deals with a structural design and thermal analysis of a module coil for a 750 kW-class HTS generator. The conduction and radiation heat loads of the module coils were analysed using a 3D finite element method program. As a result, the total thermal load was less than the cooling capacity of the cryo-cooler. The design results can be effectively utilized to develop a superconducting generator for wind power generation systems.

• Journal of Ginseng Research
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• v.43 no.2
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• pp.209-217
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• 2019

Background: Ginseng is a traditional herbal medicine for human health. Ginseng contains a bioactive ligand named gintonin. The active ingredient of gintonin is lysophosphatidic acid C18:2 (LPA C18:2). We previously developed a method for gintonin-enriched fraction (GEF) preparation to mass-produce gintonin from ginseng. However, previous studies did not show the presence of other bioactive lipids besides LPAs. The aim of this study was to quantify the fatty acids, lysophospholipids (LPLs), and phospholipids (PLs) besides LPAs in GEF. Methods: We prepared GEF from white ginseng. We used gas chromatography-mass spectrometry for fatty acid analysis and liquid chromatography-tandem mass spectrometry for PL analysis, and quantified the fatty acids, LPLs, and PLs in GEF using respective standards. We examined the effect of GEF on insulin secretion in INS-1 cells. Results: GEF contains about 7.5% linoleic (C18:2), 2.8% palmitic (C16:0), and 1.5% oleic acids (C18:1). GEF contains about 0.2% LPA C18:2, 0.06% LPA C16:0, and 0.02% LPA C18:1. GEF contains 0.08% lysophosphatidylcholine, 0.03% lysophosphatidylethanolamine, and 0.13% lysophosphatidylinositols. GEF also contains about 1% phosphatidic acid (PA) 16:0-18:2, 0.5% PA 18:2-18:2, and 0.2% PA 16:0-18:1. GEFmediated insulin secretion was not blocked by LPA receptor antagonist. Conclusion: We determined four characteristics of GEF through lipid analysis and insulin secretion. First, GEF contains a large amount of linoleic acid (C18:2), PA 16:0-18:2, and LPA C18:2 compared with other lipids. Second, the main fatty acid component of LPLs and PLs is linoleic acid (C18:2). Third, GEF stimulates insulin secretion not through LPA receptors. Finally, GEF contains bioactive lipids besides LPAs.

• Asian Journal for Public Opinion Research
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• v.7 no.2
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• pp.94-112
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• 2019

Objective: The objective of this study was to compare the quality of life (QOL) of patients with end-stage renal disease (ESRD) between patients receiving hemodialysis (HD) and patients receiving continuous ambulatory peritoneal dialysis (CAPD) and to compare personal characteristic factors relating to the quality of life in patients with ESRD. Method: This study used a descriptive research design. The sample was recruited using purposive sampling that included 76 ESRD patients receiving either HD or CAPD at a dialysis clinic in Phraphutthabat Hospital, Saraburi Province, Thailand. Data was collected using the Quality of Life Questionnaire for Chronic Kidney Disease ($KDQOL-SF^{TM}$) version 1.3. Independent t-test and ANOVA procedures were used to analyze study data. Results: The results revealed that the HD patients had a moderate level of QOL. The highest scoring dimension of QOL was the encouragement of staff at the dialysis unit and patient satisfaction with the treatment (${\bar{X}}=100$, SD=.00), followed by social support (${\bar{X}}=89.29$, SD =16.88) and cognitive function (${\bar{X}}=88.57$, SD=11.82). On the other hand, the lowest scoring QOL dimension was physical problems (${\bar{X}}=50$, SD=51.89), and pain (${\bar{X}}=50$, SD=39.03), followed by work status (${\bar{X}}=53.57$, SD=45.84) and burden from kidney disease (${\bar{X}}=58.48$, SD=31.07). The CAPD patients also had a moderate QOL. The highest scoring QOL dimension was the encouragement of staff in the renal unit and patient satisfaction with the treatment (${\bar{X}}=100$, SD=.00), followed by social support (${\bar{X}}=95.61$, SD=14.20) and cognitive function (${\bar{X}}=88.83$, SD=13.52). The worst scoring QOL dimensions were work status (${\bar{X}}=44.44$, SD=42.72), general health (${\bar{X}}=53.61$, SD=39.05), and pain (${\bar{X}}=62.70$, SD=41.14). The difference overall and in each dimension of QOL in ESRD patients who were treated with HD and CAPD was not statistically significantly different. The QOL was not significantly different among patients with different personal characteristics except for income and duration of treatment; in those cases, the difference in QOL was statistically significant (p=.05). Conclusion: The overall QOL and life expectancy of patients with ESRD treated with HD and CAPD are not affected by gender, age, marital status, education, occupation, or type of health coverage. QOL was not significantly different, except for patients with different incomes and duration of renal replacement therapy, whose QOL was significantly different. The QOL of patients receiving dialysis should be studied to develop a QOL program for patients with chronic kidney disease who receive dialysis.

• Journal of Korea Foundry Society
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• v.38 no.6
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• pp.111-120
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• 2018

In this study, the effects of two different casting methods (gravity casting and, diecasting) and various solid-solution conditions on the mechanical properties of ASC (Al-10.5wt%Si-1.75wt%Cu) and ALDC12 (Al-10.3wt%Si-1.72wt%Cu-0.76wt%Fe-0.28wt% Mn-0.32wt%Mg-0.9wt%Zn) alloys were investigated. A thermodynamic solidification analysis program (PANDAT) was used to predict the liquidus, solidus, and phases of the used alloys. In the results of an XRD analysis, ${\beta}$-AlFeSi peaks were observed only in the ALDC12 alloy regardless of the casting method or SST (solid-solution treatment) conditions. However, according to the results of a FE-SEM observation, both ${\theta}(Al_2Cu)$ and ${\beta}$-AlFeSi were found to exist besides ${\alpha}$-Al and eutectic Si in the gravity-casted ASC alloy at $500^{\circ}C$ after a SST of 120min. The ${\alpha}$-AlFeSi and ${\beta}$-AlFeSi phases including the eutectic phases were also found to exist in the ALDC12 alloy. The results of a microstructural observation and analyses by XRD, FE-SEM and EDS were in good agreement with the PANDAT results. The gravity-casted ALDC12 and ASC specimens showed the highest Y.S. and UTS values after aging for three hours at $180^{\circ}C$ after a SST at $500^{\circ}C$ for 30min. At longer solid-solution treatment times at $500^{\circ}C$ in the gravity-casted ALDC12 and ASC specimens, the elongations of the ASC alloys increased, whereas they decreased slightly in the ALDC12 alloys.

• Journal of the Korean earth science society
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• v.42 no.2
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• pp.221-244
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• 2021

To examine the limitations of the the Blosser's (1973) 'Question Category System for Science', which is mainly applied to research in science education in Korea, we analyzed 30 hours of class conversation in a small group program (for first-year middle school students) with a researcher participating as a teacher. When classified according to Blosser's (1973) classification system, distinguishing between 'open and closed questions' was difficult. Questions with the same content were classified into different types depending on their context, whereas some questions could not be classified appropriately. Additionally, higher-level questions (open questions) were not more effective than lower-level questions (closed questions) in improving students' thinking ability or participation in class. The questionnaire's effect differed depending on the information provided by the teacher before questioning, and in many cases, previous question influenced the next questions. However, in the science education questionnaire research based on Blosser's (1973) classification, which is mainly conducted in Korea, each individual question is classified according to the cognitive level, disregarding the influence of context and prior and subsequent questions and the quality of instructions is evaluated by the frequency of higher level questioning. The results of this study indicate that the method of evaluating instruction quality based on the frequency of high-level questioning, which is currently conducted in domestic science education inquiry research, should be avoided.