• Journal of Korea Water Resources Association
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• v.57 no.5
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• pp.359-369
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• 2024

Korea prepares for potential floods by designating June 21st to September 20th as the flood season. However, many dams in Korea have suffered from extreme floods caused by different climate patterns, as in the case of the longest consecutive rain of 54 days in the 2020's flood season. In this context, various studies have tried to develop novel methodologies to reduce flood damage, but no study has ever dealt with the validity of the current statutory flood season thus far. This study first checked the validity of the current flood season through the observation data in the 21st century and proved that the current flood season does not consider the effects of increasing precipitation trends and the changing regional rainfall characteristics. In order to deal with these limitations, this study suggested seven new alternative flood seasons in the research area. The rigid reservoir operation method (ROM) was used for reservoir simulation, and the long short-term memory (LSTM) model was used to derive predicted inflow. Finally, all alternatives were evaluated based on whether if they exceeded the design discharge of the dam and the design flood of the river. As a result, the floods in the shifted period were reduced by 0.068% and 0.33% in terms of frequency and duration, and the magnitude also decreased by 24.6%, respectively. During this period, the second evaluation method also demonstrated that flood decreased from four to two occurrences. As the result of this study, the authors expect a formal reassessment of the flood season to take place, which will ultimately lead to the preemptive flood response to changing precipitation patterns.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.1
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• pp.96-101
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• 2003

This study was done to analyze the contents of minerals, to compare the measured values of calcium and the labeled values in food labeling and to analyze the ratio of calcium to other minerals in 43 calcium-fortified Food products sold in markets in Seoul, Korea. Content of minerals such as Ca, P, Mg, Na, K, Fe, Cu, Zn was measured by atomic absorption or colorimetric method after dry-ashing or wet-ashing. The measured values of calcium were ranged 65.5~343.9% of the labeled values in 43 calcium-fortified products. In 21 calcium-fortified food products, the measured calcium values were ranged 120～160% of the labeled values, and in three drinks those were less than 80% of the labeled, which is not acceptable to the food regulation. The ratios of Ca:P were 2.63$\pm$1.99 (mean$\pm$SD) in grain Products, 1.79$\pm$0.39 in Ramyuns, 2.80$\pm$0.53 in retort pouch food products and 8.35$\pm$12.87 in drinks. The Ca:Fe ratios were 126.33$\pm$44.36 in grain products, 130.65$\pm$34.67 in Ramyuns, 120.31$\pm$71.15 in retort pouch food products and 700.25$\pm$553.70 in drinks. The ratios of Ca:Mg were 11.86$\pm$5.40 in grain products, 9.29$\pm$1.34 in Ramyuns, 9.09$\pm$2.09 in retort pouch food products and 32.50$\pm$41.35 in drinks. The P:Mg ratios were 4.11$\pm$1.54 in grain products, 4.17$\pm$0.67 in Ramyuns, 2.58$\pm$0.45 in retort pouch food Products and 2.59$\pm$2.50 in drinks. These results suggest calcium contents and the ratio of calcium contents to other minerals in calcium-fortified food products should be strictly controlled.

• Pediatric Infection and Vaccine
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• v.4 no.1
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• pp.116-125
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• 1997

Purpose : Studies on the duration of immune response against Japanese encephalitis virus from recipients with JE vaccine (Nakayama-NIH strain) in Korea. Methods : To determinate the immune response and the duration of antibody against JE vaccine, 213 students were examined since 1994 using hemmaglutination inhibition test and plaque reduction neutralization test (PRNT). Results : 24 months after the first vaccination, haemmaglutination inhibition and neutralizing antibody maintained from the recipients 63.4% (>1:20) and 100% (>1:20), respectively. In April 1996, one dose booster to the same recipients those who were vaccinated in 1994, the GMT antibody for HI and PRNT titer were both increased from 1:11.6 to 1:13.2 and 1:275.7 to 1:348.1, respectively, after 6 months booster (after 30 months from the initial vaccination). This results showed that the antibody from the active immunity could be maintained more than 12 months after the initial vaccination. On the basis of these results, inactivated killed JE vaccine (Nakayama-NIH strain) using for preventing against JE purpose seems to produce antibody enough to protect against JE at present. Conclusions : Along with the results of this study demonstrating duration of antibody, the active immunization could be maintained as long as by initial vaccination of 2 doses, a single dose of booster vaccination made during a period of 1 month to 12 months and the successive booster vaccination by 2 or 3 year intervals. However, the immunization schedule should be concerned with both epidemiology of disease and the immune response of vaccinated individuals.

• Journal of the Mineralogical Society of Korea
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• v.27 no.4
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• pp.251-262
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• 2014

Inorganic binders were studied in order to apply a conservation material for stone monument. A pure inorganic binder and 3 species of inorganic binder which contain additives on the basis of a pure inorganic binder were selected as test samples. Through the application of inorganic binders on Geochang granite investigate their influences on stone. pH 4.0 and 5.6 acid solution, respectively were manufactured on the basis of the acidity of domestic rainfall. Alkaline water with pH 8.0 and deionized water with pH 6.85 were prepared as control group. Changes in weights of inorganic binders were not definite according to the acidity of water while weight losses in inorganic binder type were greater after reaction with the water. The compressive strengths of pure inorganic binder was largest before the test but its decrease rate were larger after reaction with the water. Water absorption rate of inorganic binders are 6.72 to $12.44kg/m^2{\cdot}t^{1/2}$ after reaction with the water. Such high absorption was considered that it forced water to move deep into inorganic binder and made the components of inorganic binder dissolve. Acidities of the water of pH 4.0, 5.6, 6.85 and 8.0, respectively were changed to pH 9.0-10.0 after reaction with the inorganic binders. Ion concentrations in the water changed after reaction with the inorganic binders and $Mg^{2+}$, and $K^+$ significantly increased, dissolved from the binder. The high concentration of ions detected showed that the binder reacted with water and formed white salts with high solubility such as $MgSO_4{\cdot}nH_2O$, $KNO_3$. Ion concentrations significantly decreased from the binder after treatment with consolidant and water repellent.

• Journal of Korean Society of Forest Science
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• v.107 no.3
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• pp.237-244
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• 2018

This study was carried out in order to secure basic data of seedling mass propagation technique of Rhododendron mucronulatum which is the native tree species of Korea by surveying the characteristics of its fruit and seed. The fruits were collected at Mt. Goryeo in Ganghwa-gun on different dates in 2013; August 26th, September 5th, September 12th, October 4th. The seed germination test was carried out at 5, 10, 15, 20, 25 and $30^{\circ}C$. Moisture content of the fruit was highest (54.5%) in the fruit collected on September 5th. Number of the seeds in a fruit was 91.3 to 116.3, regardless of the collection date. Seed length was highest ($1947.4{\mu}m$) in the seeds collected on October 4th and seed width was highest ($727.3{\mu}m$) in the seeds collected on September 12th. Germination rate of the seeds was highest at $25^{\circ}C$ regardless of the seed collection date, which showed the highest value(27.3%) in the seeds collected September 12th. Meanwhile, the seeds were not germinated not at all at 5, 10 and $30^{\circ}C$. $T_{50}$ and mean germination time of the seeds got shorter at the higher temperature. Germination uniformity got lower when the collection date got later. Germination speed of the seeds was fastest at $25^{\circ}C$. According to the results of this study, it seems that the appropriate time to collect fruit and seed is between September 12th and October 4th, and the appropriate temperature for the seed germination is $25^{\circ}C$.

• Journal of Korean Society of Transportation
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• v.24 no.2 s.88
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• pp.91-100
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• 2006

This paper examines the situation and tasks of UK rail privatization, especially focusing on after the Hatfield rail accident. Earlier research which focused on the UK's Privatization had little knowledge of the explanations for recent changes. Moreover they had difficulty making a direct comparison between national rail and the privatized rail. Therefore we aye left without a good explanation which has a comprehensive perspective. I attempt to show the change in the rail privatization Process and its outcome, focusing on after the Hatfield rail accident. This Paper argues that the UK's vail privatization process has a regulatory framework which is too complicated with overlapping responsibilities that brought about inefficiency, increasing costs and a superficial safety regime. Especially the planning of rail and infrastructure maintenance did not come to play an appropriate role. However after 2000, the government took charge of setting the strategy for railways, and the Office of Rail Regulation covered safety performance and cost. explain that these changes present a good opportunity to solve the problem of passing the buck for poor performance. Through the analysis, I find that the passenger rail network is well-suited to deliver long distance business and commuters and that the subsidy from the government is decreasing. However, performance, for example punctuality and reliability. should be improved. Especially the Hatfield rail accident caused a reduction in the satisfaction of passengers. In future. the problems of rising costs and monopoly franchise system should be addressed.

• Korean Journal of Weed Science
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• v.3 no.2
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• pp.143-150
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• 1983

Red rice (local name "Sore") as a weed has been a serious threat to rice production in direct-seeded rice culture in Ganghwagun, Gyeonggi province. In the Ganghwagun 508 ha out of 1,420 ha in the Samsanmyeon area is infested with red rice. The average lowland rice yield is about 4,300 kg/ha in the Ganghwagun, but the average upland rice yield is about 2,000 kg/ha in infested area. This study was carried out in order to clarify the ecological characteristics of red rice and factors affecting the competitive ability of five red rice varieties, collected from Samsanmyeon in 1981, with rice cultivar. Five varieties-Monggeunsare, Salsare, Ginkaragsare, Galsaegsalsare, Galsaegkaragsare-showed the same morphological characteristics of cultivated Japonica type, Chuncheongbyeo, but red rice tillers more profusely, is taller and lodges more easily than Chucheongbyeo. It shatters easily about 10-15 days after heading date, and at this time the hull is discolored in yellow or dark brown. There are many types of red rice with short or long owns on the spikelet, occasionally with or without own on the spikelet in the same hill, and the grains are short or long. In red reice leaf blast occurs more severely than in cultivated Indica/Japonica type, Teabaegbyeo, particulary serious in Monggeunsare. When red rice invaded in direct-seeded rice, number of panicles of rice became reduced more than other yield components.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.44 no.2
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• pp.171-181
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• 2018

Genistein is one of the representative isoflavone compounds isolated from soybeans and has been studied very well for its anti-aging and anti-inflammatory activity through previous studies. However, although genistein exhibits high solubility in organic solvents, it shows low bioavaility due to the low water solubility. In this study, we compared directly the functional difference between genistein and genistein cyclodextrin complex which has the improved water solubility and stability by cell based assay. Cell cytotoxicity experiment were carried out on RAW264.7 with CCK-8 assay and cytotoxicity was appeared from $10{\mu}g/mL$, thereby maximum concentration was set to $10{\mu}g/mL$ in all condition. We discovered that genistein CD complex suppressed NO production and iNOS expression as concentration dependent manner in the condition of LPS rather than genistein. Also, we could understand that genistein CD complex was able to down-regulate mRNA expression of anti-inflammatory cytokines such as $IL1-{\alpha}$, $IL1-{\beta}$, IL-6, and $TNF-{\alpha}$ as concentration dependent manner in the presence of LPS. In addition, we verified that genistein CD complex increased TEER of HaCaT human keratinocyte cells as concentration dependent pattern and stimulated cell division and migration rather than genistein in cell migration assay. Thus, it is expected that it can be used as an effective cosmetic raw material for improving atopic dermatitis or skin barrier if clinical studies on skin regeneration and skin barrier of the genistein CD complex are carried out.

• Journal of radiological science and technology
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• v.36 no.2
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• pp.99-110
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• 2013

In the medical field, the necessity of education growth for the professional Radiation Technologists has been emphasized to become experts on radiation and the radiation field is important of the society. Also, in hospitals and companies, important on thesis is getting higher in order to active and cope with rapidly changing internal and external environment and a more in-depth expert training, the necessity of new teaching and learning model that can cope with changes in a more proactive has become. Thesis writing classes brought limits to the in-depth learning as to start a semester and rely on only specific programs besides, inevitable on passive participation. In addition, it does not have a variety opportunity to present, an actual opportunity that can be written and discussed does not provide much caused by instructor-led classes. As well as, it has had a direct impact on the quality of the thesis, furthermore, having the opportunity to participate in various conferences showed the limitations. In order to solve these problems, in this study, writing thesis has organized training operations as a consistent gradual deepening of learning, at the same time, the operational idea was proposed based on the connectivity integrated operating and effective training program & instructional tool for improving the ability to perform the written actual thesis. The development of teaching and learning model consisted of 4 system modeling, scaffolding, articulation, exploration. Depending on the nature of the course, consisting team following the personal interest and the topic allow for connection subject, based on this, promote research capacity through a step-by-step evaluation and feedback and, fundamentally strengthen problem-solving skills through the journal studies, help not only solving the real-time problem by taking wiki-space but also efficient use of time, increase the quality of the thesis by activating cooperation through mentoring, as a result, it was to promote a positive partnership with the academic. Support system in three stages planning subject, progress & writing, writing thesis & presentation and based on cognitive apprenticeship. The ongoing Coaching and Reflection of professor and expert was applied in order to maintain these activities smoothly. The results of this study will introduce actively, voluntarily and substantially join to learners, by doing so, culture the enhancement of creativity, originality and the ability to co-work and by enhance the expertise of based-knowledge, it is considered to be help to improve the comprehensive ability.

• Journal of dental hygiene science
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• v.12 no.6
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• pp.675-681
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• 2012

Korean Ministry of Health and Welfare started to implement oral health hub center to provide oral health preventive program and dental treatment to public, especially dental vulnerable class in 2006. But, there is no applicant area to implement it regardless of national budget arrangement in 2012. This study is aimed to investigate the reason not to be implemented and requirements of implementation. 293 among 1,000 public dental hygienists in the area where have not implemented oral health hub center were surveyed in Korea from April to July in 2012 through convenience sampling. The questionnaire consisted of the reason why oral health hub center have not been implemented, the requirement of implementation, duty area and duty position et al. After removal of insufficient responses, 217 questionnaires were analyzed by t-test and ANOVA using SPSS 20.0. The reason why oral health hub center have not been implemented were deficiency of the priority list as compared with other health program (72.4%), space insufficiency (71.4%), regional budget insufficiency (70.5%), will insufficiency of oral health promotion (70.5%) and manpower insufficiency (62.7%). The first requirement of implementation were space expansion and regional budget expansion, followed by reduction of record-originated and administrative tasks, understanding on oral health program of higher ranking public officials in health center, manpower expansion, reduction of other tasks than oral health program and volunteer source expansion. Budget insufficiency and manpower insufficiency in Metropolis were ranked higher than other area (p<0.05). The group not to discuss oral health hub center graded each reason not to be implemented significantly higher than the other group (p<0.05). We suggested that to promote the importance of public oral health program be needed to public and higher ranking public officials to implement oral health hub center. In addition, we insisted that more dental manpower and budget be needed for reduction of oral health inequity in metropolis.