• Journal of the Korean Society of Radiology
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• v.15 no.5
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• pp.715-721
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• 2021

In radiation brachytherapy, the wrong source location may cause excessive dose to normal tissue. Therefore, research on digital dosimeters is being made to replace the analog detection method. Therefore, in this study, a lead (II) oxide (PbO) dosimeter applied with a passive layer (PL) was fabricated as a basic study to improve the dosimeter performance. Afterwards, reproducibility, linearity, and distance dependence were evaluated to analyze the performance of the Ir-192 source under irradiation conditions. The reproducibility of the PL-PbO dosimeter was 0.40%, which satisfies the evaluation criteria of 1.5%, and showed improved results compared to the PbO dosimeter. Linear function R2 showed excellent results as 0.9995, and slope analysis through regression analysis of the linear function was excellent in PL-PbO. The distance dependence of the PL-PbO dosimeter was +0.599 higher than that of PbO when the slope obtained through regression analysis of the power function was compared with the inverse square value. This study presents the effects and measurement variables according to the measurement configuration of the solid-state dosimeter, and can be used in various radiation detection fields.

• Cross-Cultural Studies
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• v.49
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• pp.151-179
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• 2017

This paper explores envy and jealousy caused by conflicts between youth and old age in Philip Roth's The Dying Animal and Bumshin Park's Eungyo. In Roth's Novel, David became envious and jealous of a fictional man when he imagined "the pornography of jealousy." In this pornography, his imagined rival was a young man who was once David himself but was no longer young who might steal Consuela away from him. In this sense, David's envy towards this young rival can be called "self-envy." David considered sex an act of revenge on death. But his envy and jealousy undermined his power and effect. In Eungyo, envy and jealousy arose between Lee and Seo when they came into conflict because of Lee's literary talent and Eungyo. At first, Seo admired Lee. But he grew envious of Lee's talent when he gained popularity and success by publishing Lee's novels under his own name. He was engulfed in jealousy when he detected Lee's sexual desire for Eungyo. He even insulted Lee's old age, which enraged Lee. Lee's rage was mixed with his envy toward the young and his sense of betrayal against Seo. With Seo's death, all these negative feelings disappeared. Instead, Lee was captivated by the pulsing breath of life and its beauty he observed in Eungyo.

• Food Engineering Progress
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• v.14 no.2
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• pp.135-145
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• 2010

In order to enhance overall quality of the Backsulki, a sweet potato flour (SPF) which is rich in sugar and dietary fiber was added into the rice flour at 0, 5, 15, and 25% (w/w, db) ratios. Quality changes of the products were evaluated by storing at 5, 15, and 25$^{\circ}C$ for 4 days. Water binding capacity, swelling power, and solubility of the products increased as the SPF increased. Hunter colorimetric a- and b-value increased while L value of the products decreased as the SPF increased. Retarded retrogradation of the flour mixtures containing the SPF was shown from the DSC thermogram as indicated by the decreased $\Delta$H values. Increases in $T_{i}$ and $T_{p}$ values in relation with the starch gelatinization were shown from the DSC thermogram with a temperature margin of 15-20$^{\circ}C$ as the SPF increased. Increases in softness along with decreases in springiness and chewiness of the products were shown as the SPF increased. It was not so much the storage temperature as the added SPF affected the final texture of the products. Retarded growth of the total microbes of the products was noted by the added SPF during storage at 25$^{\circ}C$ for 3 days. Regarding the above and additional sensory preference scores of the products, a 15%(w/w) level of the SPF was suggested as optimum for the best Backsulki with improved qualities.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.11
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• pp.529-535
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• 2018

The range extender vehicle runs on a mechanism that allows the small power generation engine to start in the most efficient specific operating range to charge the battery and extend the mileage. In this study, we developed a step motor type intake air supply system that replaces existing throttle body system to develop a simple low cost control logic system. The system was applied to the existing base engine, and in order to improve the performance by increasing the amount of intake air, the effect of changing the length of the intake and exhaust manifold was experimentally examined. As a result, the Type B intake air control actuator operated by one step motor showed higher performance than the Type A in all the operation region, but the performance was lower than that of the base engine due to the increase of flow resistance. To improve this, it was confirmed that the engine performance was improved at both speeds of 2200rpm and 4300rpm when the 140mm adapter was installed in the intake manifold and when the newly designed 70mm exhaust manifold was applied. Through this process, high - precision operation control was realized by connecting the generator load to the optimized engine for the range extender electric vehicle. Experimental results showed that the speed change rate was within ${\pm}2.5%$ at 2200rpm in 1st stage and 4300rpm in 2nd stage and the speed follow-up result of 610 rpm/s was obtained when the speed was increased from 2200rpm to 4300rpm.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.9
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• pp.127-132
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• 2019

This study examined the change in the attention of University students after being given Transcranial Direct Current Stimulation (tDCS). The participants were divided randomly into two group (tDCS vs. Control). tDCS was applied to 37 university students ($23.08{\pm}3.33years$). The tDCS group was applied 2 mA, for 13 minutes twice over a 26 minute period ($n_1=19$). The control ($n_2=18$) was not applied after padding and was applied twice for 13 minutes over a 26 minute period. This study was conducted from September 3 to 28, 2018 and three times a week for a total of four weeks. The electroencephalogram was confirmed to affect attention. tDCS showed significant improvement in the results in the sensory motor rhythm wave (p<0.01, 95% CI: -1.955, -0.459), middle beta wave (p<0.05; 95% CI: 0.027, 0.943), and power ratio (p<0.01, 95% CI: -1.764, -0.315). The results showed that tDCS application increased the attention ability significantly. These results can be applied to attention deficit disorder (ADHD) patients and college students.

• Journal of Industrial Convergence
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• v.19 no.5
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• pp.129-137
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• 2021

The present study attempted to identify how the knowledge and risk perception of nursing students regarding COVID-19 impact COVID-19 preventive behaviors. This study collected data from May 1st to September 20th, 2021, using a self-reported questionnaire targeting 184 nursing students. The collected data were analyzed using Independent t-test, One-way ANOVA, and Multiple regression. The research results indicated that the knowledge(r=.15, p=.019) and risk perception(r=.13, p=.036) of nursing students regarding COVID-19 had a positive correlation with COVID-19 preventive behaviors. The factor that impacted the COVID-19 preventive behaviors of the subjects was COVID-19 knowledge, which had an explanatory power of 4%. Therefore, it is necessary to develop an educational intervention program that enables nursing students to obtain the correct knowledge regarding COVID-19 and improves preventive behaviors.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.2
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• pp.148-159
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• 2021

The purpose of this study was to investigate the influence of critical thinking disposition and communication competence on the problem-solving confidence satisfaction of nursing students. The data was collected using questionnaires completed by 215 nursing students in G city from November 1 to November 30, 2019. Data was analyzed using SPSS version 22.0. The data analysis showed that the mean score for critical thinking disposition was 3.69±0.37, communication competence 3.72±0.46, and problem-solving confidence 3.56±0.41. There was a significant positive correlation between critical thinking disposition and communication competence (r=.588, p<.001). critical thinking disposition and problem-solving confidence (r=.462, p<.001), communication competence, and problem-solving confidence (r=.255, p<.001). As per the regression analysis, the factors that affect problem-solving confidence were academic achievement, critical thinking disposition, the motive for selecting nursing science, and gender with an explanatory power of about 33.8%. Conclusions: This study showed that problem-solving confidence correlated with critical thinking disposition and communication competence. Therefore, to increase the critical thinking disposition and communication competence and thus enhance the problem-solving confidence of nursing students, it is necessary to develop and apply appropriate teaching methods and non-contact education programs.

• Journal of Food Hygiene and Safety
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• v.36 no.4
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• pp.353-362
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• 2021

Ecklonia stolonifera, which belongs to the family Laminariaceae, is an edible perennial brown marine alga that is widely distributed, and is rich in polyphenols, including dieckol. Here, we investigated the radical scavenging activities of E. stolonifera extract (ESE) using various in vitro models. We further evaluated the effect of ESE on the cholesterol secretion inhibition activity in HepG2 cells, as well as the hydroxymethylglutaryl-coenzyme A (HMG-CoA) reductase activity. Our results showed that the total phenol, total flavonoid, and dieckol contents of ESE were 9.64±0.04 mg GAE/g, 2.72±0.08 mg RE/g and 27.42±0.66 mg/g, respectively. The antioxidant activity of ESE increased in a dose-dependent manner. In addition, the ESE inhibited cholesterol secretion from HepG2 cells with anti-HMG-CoA reductase activity. These results suggested that ESE possesses antioxidant and anti-cholesterol activities, and can therefore be used as a preclinical bioresource for development of health functional foods.

• The Journal of the Convergence on Culture Technology
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• v.7 no.3
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• pp.27-34
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• 2021

The purpose of this study was to investigate the effect of ethical decision making confidence in nursing students and to provide the basic data of to control ethical decision making confidence. Data were collected from 205 nursing students in B city and analyzed by t-test, ANOVA, Pearson correlation coefficient, and multiple regression using SPSS/WIN 22.0. The degree of ethical decision making confidence in nursing students was 3.83±.62. There were significant differences in ethical decision making confidence with respect to gender(t=2.118, p=.037), achivement of life(F=3.851, p=.023). There was positive correlation between ethical decision making confidence and ethical value(r=.153, p=.028), critical thinking disposition(r=.477, p<.001), and professional self concept(r=.566, p<.001). The factors affecting the ethical decision making confidence of the study subjects were critical thinking disposition(β=.254, p<.001), professional self concept(β=.418, p<.001), with an explanatory power of 35.1%. Through this research requires the fellow study to determine the factors affecting ethical decision making confidence of nursing students.

• Nuclear Engineering and Technology
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• v.54 no.9
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• pp.3250-3259
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• 2022

A new approach to the use of rice straw as a difficult-to-recycle agricultural waste was proposed. Potassium aluminosilicate was obtained by spark plasma sintering as an effective material for subsequent immobilization of ¹³⁷Cs into a solid-state matrix. The sorption properties of potassium aluminosilicate to ¹³⁷Cs from aqueous solutions were studied. The effect of the synthesis temperature on the phase composition, microstructure, and rate of cesium leaching from samples obtained at 800-1000 ℃ and a pressure of 25 MPa was investigated. It was shown that the positive dynamics of compaction was characteristic of glass ceramics throughout the sintering. Glass ceramics RS-(K,Cs)AlSi₃O₈ obtained by the SPS method at 1000 ℃ for 5 min was characterized by a high density of ~2.62 g/cm³, Vickers hardness ~ 2.1 GPa, compressive strength ~231.3 MPa and the rate of cesium ions leaching of ~1.37 × 10^-7 g cm^-2·day^-1. The proposed approach makes it possible to safe dispose of rice straw and reduce emissions into the atmosphere of microdisperse amorphous silica, which is formed during its combustion and causes respiratory diseases, including cancer. In addition, the obtained is perspective to solve the problem of recycling long-lived ¹³⁷Cs radionuclides formed during the operation of nuclear power plants into solid-state matrices.