• The Journal of Korean Academy of Prosthodontics
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• v.42 no.4
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• pp.344-355
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• 2004

Statement of problem: For a long time, many of denture base acrylic resins have been used for edentulous and partial edentulous patients because of easy manipulation and good mechanical properties, but its esthetic aspect has not been commented enough. Denture base acrylic resins also has caused esthetic problems due to discoloration or staining as in esthetic restoration. Many researches and reports have treated the problems and accomplished esthetic improvement. But these researches and reports dealt with general food colors or beverages, not with fermented foods. Purpose: This study is designed to assess what fermented foods, such as soy sauce, gochujang, and toenjang that many of Koreans have taken in, influence on the color and hardness variation of denture base acrylic resins. Materials and methods: For the procedure, twelve disks per 4 denture base acrylic resins were fabricated with a thickness of 2mm and 16mm in diameter. Each seven specimen were measured for discoloration with spectrophotometer, while the others, five specimen, for surface hardness change with Barcol hardness tester, over time. Each 12 specimen were immersed into the 4 beakers of fermented foods(soy sauces, gochujangs, toenjangs, deionized water), and $L^{*},a^{*}$, and $b^*$ values were measured for the color difference$({\Delta}E^*)$, on the 1st, 7th, and 28th day with spectrophotometer, with the measurement of surface hardness change. Each data observed was processed statistically. Results: The findings are as follows; Discoloration 1. All of denture base resins was not influenced by the kind of fermented foods, except for $QC20^{(R)}$ 2. Soy sauce and red pepper paste caused more change for denture base resins than deionized water and soy bean paste, except for Perform$^{(R)}$ 3. Most significant change was shown in Lucitone 199$^{(R)}$, whereas Perform$^{(R)}$ results in the least change for all immersed solution, with no statistical significance. Hardness change 1. Barcol hardness values in deposited specimens have been changed low degree, but with significant statistical change according to the kind of food and duration. 2. Lucitone$^{(R)}$ 199 as significantly lower Barcol hardness value than others do. Conclusion: Based on the above results, it suggests that the habitual intake of fermented foods is not helpful for the color stability of denture base acrylic resins because Soy sauce and red pepper paste mainly caused discoloration and surface hardness change. Particularly $Lucitone199^{(R)}$ shows specific discoloration and low surface hardness values. Therefore, it is recommended giving caution patients with denture of $Lucitone199^{(R)}$ especially against the habitual intake of fermented foods like soy sauce and red pepper paste.

• Journal of Bio-Environment Control
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• v.14 no.4
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• pp.245-253
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• 2005

This study was carried out to determine the optimum EC supply by accumulation amount of solar radiation in closed system. EC concentration of drainage was higher than that of supply. The higher EC concentration of supply was, the lower pH of drainage was. It was no difference in the quality of cut rose 'Nobles' (Rosa hybrida), stem length, stem diameter, leaf number, petal length, and petal diameter by EC treatment by season. The yield was higher about $6\%$ in treatment of EC $1.3dS{\cdot}m^{-1}$ in April and May, about $10\%$ in treatment of EC $10dS{\cdot}m^{-1}$ in June, July and August, and about $10\%$ in treatment of EC 1.0 or $1.3dS{\cdot}m^{-1}$ in September and October than the others. In general, the yield of the cut rose was higher in treatment of (B) EC 1.3 mS/cm in spring, EC $1.0dS{\cdot}m^{-1}$ in summer, EC $1.3dS{\cdot}m^{-1}$ in autumn, and EC$1.6dS{\cdot}m^{-1}$ in winter.

• Journal of the Korean Society of Radiology
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• v.11 no.4
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• pp.279-287
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• 2017

The purpose of this was to study and analyze smart learning the self directed learning, self efficacy, learning satisfaction about department of radiology in a college. For this study total students 74 in 2classes were surveyed at the end of semester. Compared to use smartphones one group and not use smartphones one group for study in a class. The research data was analyzed using SPSS also self directed learning, self learning efficacy, learning satisfaction analyzed t-test, general character was analyzed two group(one : Used smart learning other : not Used smart learning) ${\chi}^2-test$. First, Used smart learning group is more higher than not Used smart learning group in a self learning efficacy, self directed learning, learning satisfaction. Second, during the smart learning classes a students appeared a positive response. Suggest to change a paradigm in a radiology classes so we have to improve a teaching skills this solution recommend is two way communication. In conclusion, smart learning applied for classes of college is meaningful as a new teaching, which can be change gradually learning satisfaction by teaching methods.

• Journal of Korean Tunnelling and Underground Space Association
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• v.22 no.4
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• pp.451-468
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• 2020

Aging tunnels with small cross-sections can cause chronic traffic jams. This problem can be solved by widening the tunnel. In general, when the tunnel is expanded, the outer portion of the existing tunnel is excavated through a mechanical or blasting method. Such excavation affects not only the surrounding ground but also the existing tunnel. The application of the pre-cutting method can be a solution to these problems effectively. Therefore, if the widening of tunnel is performed by applying pre-cutting method, analysis of the impact of this method must be performed. In this study, in order to analyze the effect of applying pre-cutting in tunnel widening, numerical analysis is performed at six ground grades, from grade I to weathered rock. The analysis is performed with the expanding lane and the excavation length of pre-cutting as variables. In addition, the analysis is focused on the displacement of crown of the existing tunnel and the enlarged tunnel. As a result, the crown displacement of the enlarged tunnel is confirmed to converge at the same value regardless of the excavation length of the pre-cutting when the tunnel widening is completed. In the case of existing tunnels, uplift of crown occurs within 5 m of the front of the tunnel surface, and the shorter the excavation length of pre-cutting is found to be effective in preventing the occurrence of uplift.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.38-38
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• 2017

Water stress obstructs rice growth mainly by oxidative damage in biological cells to cause a reduction of leaf photosynthesis and evapotranspiration processes. In this study, exogenous application of vanillic acid (VA) and p-hydroxybenzoic acid (PHBA) to improve drought tolerance of two Oryza sativa cultivars, Q2 and Q8 was tested. The drought evaluation based on leaf phenotypes to show that both Q2 and Q8 resulted in remarkable water-stress tolerance induced by leaf spraying pretreatment of mixed solution of $50{\mu}M\;VA+50{\mu}M\;PHBA$. The mixtures of $25{\mu}M\;VA+25{\mu}M\;PHBA$ and $50{\mu}M\;VA+50{\mu}M\;PHBA$ treated on Q2 and Q8 in water deficit condition also indicated that total phenols, total flavonoids, and DPPH radical scavenging activity were significantly greater their controls. In general, the accumulation of individual phenolic acids was increased in exogenous phenolic treatments, as compared with controls. Particularly, Q2 obtained a considerable amount of endogenous PHBA after application of $50{\mu}M\;VA$, $25{\mu}M\;VA+25{\mu}M\;PHBA$, and $50{\mu}M\;VA+50{\mu}M\;PHBA$ (0.18 mg/g DW, 0.71 mg/g DW, and 1.41 mg/g DW, respectively); and a negligible content of VA (0.003 mg/g DW) appeared uniquely in the treatment of $50{\mu}M\;VA$. Similarly, Q8 also absorbed a significant quantity of PHBA in $50{\mu}M\;PHBA$, $25{\mu}M\;VA+25{\mu}M\;PHBA$, and $50{\mu}M\;VA+50{\mu}M\;PHBA$ treatments (0.15 mg/g DW, 0.15 mg/g DW, and 0.22 mg/g DW, respectively). In addition, the spraying $50{\mu}M\;PHBA$ and $25{\mu}M\;VA+25{\mu}M\;PHBA$ on Q8 leaves induced similar amount of drought tolerance of Q2 and Q8 were improved, paralleled with the increased amounts of endogenous phenolics revealed that VA and PHBA played an important role to enhance drought tolerance in rice.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.33-33
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• 2017

Water stress obstructs rice growth mainly by oxidative damage in biological cells to cause a reduction of leaf photosynthesis and evapotranspiration processes. In this study, exogenous application of vanillic acid (VA) and p-hydroxybenzoic acid (PHBA) to improve drought tolerance of two Oryza sativa cultivars, Q2 and Q8 was tested. The drought evaluation based on leaf phenotypes to show that both Q2 and Q8 resulted in remarkable water-stress tolerance induced by leaf spraying pretreatment of mixed solution of $50{\mu}M\;VA+50{\mu}M\;PHBA$. The mixtures of $25{\mu}M\;VA+25{\mu}M\;PHBA$ and $50{\mu}M\;VA+50{\mu}M\;PHBA$ treated on Q2 and Q8 in water deficit condition also indicated that total phenols, total flavonoids, and DPPH radical scavenging activity were significantly greater their controls. In general, the accumulation of individual phenolic acids was increased in exogenous phenolic treatments, as compared with controls. Particularly, Q2 obtained a considerable amount of endogenous PHBA after application of $50{\mu}M\;VA$, $25{\mu}M\;VA+25{\mu}M\;PHBA$, and $50{\mu}M\;VA+50{\mu}M\;PHBA$ (0.18 mg/g DW, 0.71 mg/g DW, and 1.41 mg/g DW, respectively); and a negligible content of VA (0.003 mg/g DW) appeared uniquely in the treatment of $50{\mu}M\;VA$. Similarly, Q8 also absorbed a significant quantity of PHBA in $50{\mu}M\;PHBA$, $25{\mu}M\;VA+25{\mu}M\;PHBA$, and $50{\mu}M\;VA+50{\mu}M\;PHBA$ treatments (0.15 mg/g DW, 0.15 mg/g DW, and 0.22 mg/g DW, respectively). In addition, the spraying $50{\mu}M\;PHBA$ and $25{\mu}M\;VA+25{\mu}M\;PHBA$ on Q8 leaves induced similar amount of VA (0.04 mg/g DW). Meanwhile, there were no trace of VA and PHBA found in controls. The levels of drought tolerance of Q2 and Q8 were improved, paralleled with the increased amounts of endogenous phenolics revealed that VA and PHBA played an important role to enhance drought tolerance in rice.

• Applied Chemistry for Engineering
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• v.5 no.3
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• pp.425-430
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• 1994

The effect of inhibitors and catalysts in the synthesis of 2-hydroxyethyl methacrylate(2-HEMA) was studied. As catalysts, triethylamine(TEA), $FeCl_3{\cdot}6H_2O$, $Cu(NO_3)_2{\cdot}2H_2O$, $AlCl_3$, $Na_2Cr_2O_7$were selected. p-Methoxyphenol (PMP) of aq. $NaNO_3$ solution was used as an inhibitor in polymerization. in aq. $NaNO_3$ inhibitor system, triethylamine (TEA), $FeCl_3{\cdot}6H_2O$, and $Na_2Cr_2O_7$, showed good catalytic effects. When p-methoxyphenol(PMP) was used as a polymerization inhibitor, the reaction was very sluggish and noneffective because the metal ion such as $Fe^{3+}$ or $Cr^{6+}$ was reduced by PMP. On the contrary, when aq. $NaNO_3$ was used as an inhibitor in polymerization, the reaction was very fast without deactivation of the metal catalysts.

• 한국해양학회지
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• v.15 no.1
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• pp.49-57
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• 1980

Toxicity of Machete on the mortality of the three different life stages, namely, hatching period, prelarval stage, and juvenile stage of carp(Cyprinus carpio Linne) was observed. The effect of the various exposure times on the mortality of the prelarval stage, and the effect of different temperatures on the toxicity during juvenile stage were also analysed. Hatchability and duration time of the carp were shown to be related to the concentration of Machete. In general, hatchability and duration time were shown to be decreased when the concentration of Machete was increased. For prelarval stage, 24hr and 48hr LC 50, and 24hr and 48hr EC 50 were observed to be 0.86mg/l and 0.43mg/l, and 0.35mg/l and 0.20mg/l, respectively. For juvenile stage, 24hr, 48hr, 96hr, and Incipient LC 50 were found to be 0.625mg/l, 0.365mg/l, 0.180mg/l, and 0.135mg/l, respectively. Apparently it was appeared that eggs were most resistant, and prelarvae were most sensitive to Machete among the three life stages. Although fish were removed from the Machete solution(3.2mg/l, and 1.8mg/l) prior to their death, continuous mortality was observed. Below 1.mg/l range, however, when concentration of Machete was lowered, the toxic effect of Machete on carp was reduced considerably even to the longtime exposure(24hours) Toxicity of Machete appeared to be related to water temperature, and it was observed that higher temperature reflected more toxicity.

• International Journal of Advanced Culture Technology
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• v.5 no.3
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• pp.24-34
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• 2017

Nail art is a kind of nail painting or decoration that adds to the beauty. Throughout making nail art, the worker was on a dusty operation with the smoothing of chemicals and nails. People working at nail shops not only use a variety of chemicals, but also experience a lot of fine powder during the process of nail trimmings. While drying the chemical adhesive, the workers often complain of eye, nose and throat discomfort. In addition, the acrylic brush is characterized by a lot of smell when washed with washing solution. Also nail art workers directly influence the worker's breathing through the work done by placing the guest's hands in a work space called a nail table. Chemical ingredients used in nail art procedures include acetone, ethyl acetic acid, toluene, butyl acetic acid, glue, and top coating of nail varnishes. Prolonged inhalation of these substances may cause dizziness, vomiting, as well as impaired respiratory system. The purpose of this study is to investigate the respiratory symptoms of nail shop workers who are likely to be affected by work in nail shop and to find out which factors have the greatest influence if they have respiratory symptoms. Therefore this study is to provide basic data on the health management system of people engaged in nail shop and to develop health education program. For this study, the data collection was collected on July 7, 2017 for the nail shop workers attending the nail art trend seminar held in Gwangju, in Korea. The data were all 236. However, except for the poor data, 208 data were used for the final analysis. The questionnaire consisted of 30 in general questions, questions about self-efficacy in 24 questions. elf-efficacy measuring tool developed by A.Y, Kim, I. Y, Park(2001). The self-efficacy questionnaire consists of 24 items and is self-reported 7-point Likert scale. The reliability of this tool was cronbach alpha = .934.The collected data were analyzed using spss 18.0. Information of Research participant performed frequency analysis. To examine the effects of personal characteristics on self-efficacy, $X^2$ analysis was conducted. And also $X^2$ analysis was conducted to analyze the coughing symptom appearance according to individual and environmental factors. A hierarchical regression analysis was used to determine which of the personal and environmental factors influenced cough symptoms.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.6 no.3
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• pp.522-531
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• 1999

This research identifies the ingress to egress primary factors that causes a patient to receive delayed emergency medical care. This material was collected between February 1st to 28th, 1998. Research envolved 4,118 people who visited the college emergency medical center in Kyeongido Province, South Korea. Medical records were examined, using the retrospective method. to determine the length of stay and the main cause for waiting. Results are as follows : 1. The age group with the highest admission rate was 10 and under, approximately 1,394 (33.9%). Followed by an even distribution for ages between 11-50 at 10-15% for their respective ranges. The lowest admission rate was 50 years and above. 2. From the 4,118 records examined, 3,489 received outpatient treatment (84.7%); 601 were admitted for inpatient care (14.6%); 25 arrived dead on arrival (0.6%); and 4 people died at the hospital. 3. Between 7PM to 12AM, 42.9% were admitted to the EMC. The hours from 9PM to 11PM recorded the highest admission rate and 5AM to 8AM was the lowest From 8PM to 12AM, the most beds were occupied. 4. For most patients. the average length of stay was approximately 2.2 hours. By medical department, external medicine was the longest for 2.8 hours. Pediatrics was the shortest for 1.6 hours. The average waiting period for inpatient admission was 2.6 hours. Inpatient admission for pediatrics and external medicine was 3.4 hours and 2.2 hours respectively. 5. Theses are primary factors for delay at EMC: 1) pronged medical consultations to decide between inpatient versus outpatient treatment, and delaying to be inpatient, 2) when you call physicians they are delayed to come 3) Understaffing during peak or critical hours, 4) Excessive consulting with different medical departments, 5) some patients require longer monitoring periods, 6) medical records are delayed in transit between departments, 7) repeated laboratory tests make delay the result, 8) overcrowded emergency x-ray place causes delay taking x-ray and portable x-ray, 9) the distance between EMC and registration and cashier offices is too far. 10) hard to control patient's family members. The best way to reduce EMC waiting and staying time is by cooperation between departments, both medical and administrative. Each department must work beyond their job description or duty and help each other to provide the best medical service and satisfy the patient needs. The most important answer to shortened the EMC point from ingress to egress is to see things from a patient point of view and begin from there to find the solution.