• Journal of the Korean Society for Railway
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• v.13 no.1
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• pp.51-57
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• 2010

The aerodynamic drag of ultra high-speed train in evacuated tube have been calculated using computational fluid dynamics and the variation of aerodynamic drag for the change of major system parameter of tube-vehicle system such as the train speed, air density, and the tunnel diameter. The aerodynamic drag in the tube increases with increasing train speed, however, the ratio of drag increase in tube is larger than that on the open field, the V square rule. The aerodynamic drag decreases with increasing tunnel diameter and increasing air density, and the drag increasing for air density is almost linear just like that on open field. For some combination of the parameters, the trend of aerodynamic drag of train showed irregularity.

• Korean Management Science Review
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• v.7 no.2
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• pp.22-42
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• 1990

This paper deals with enhancement of the high school equalization assignment system to be executed by the allied entrance examination after the applicants graduated from their middle schools. In prevailing opinion, because educational demander's will has not been considered under the current system, it whose merits have been covered is required to be improved. If the application system of the entrance examination for the high schools will be returned, a situation that it will result in irregularity of the middle school education and in overheating entrance examination seems to appear explicitly. Since the averages of the allied entrance examination score of all the high schools, achieved by the equalization-application nearest assignment system which is named by writers of this paper, are equal, our system is good for maintaining the merits of the current system. More than 50% educational demander's will has been reflected by our system, so that we come to the conclusion that our system is excellent in all the systems verified up to now. Assigning students to the high school to make an average difference between three and five score, we expect that relection rate of the educational demander's will be increased more than 60%.

• Computers and Concrete
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• v.9 no.6
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• pp.439-455
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• 2012

The interaction of plan geometry and structural configuration, a determinative factor in the earthquake behavior of buildings, has become a serious issue in the building industry in Turkey due to the poor seismic performance of R/C buildings during the latest earthquake. Consequently, designing new buildings without structural irregularities against earthquake loads is proving to be more significant. This study focuses on the effects of plan geometries on earthquake performances of buildings. In that respect, structural irregularities in the plan are investigated in detail based on the Turkish Earthquake Code (TEC 2007). The study is based on five main parametric models and a total of 40 sub-models that are grouped according to their plan geometries with excessive projections such as L-shaped, H-shaped, T-shaped and U-shaped models. In addition to these, a square model without any projections is also generated. All models are designed to have the same storey gross area but with different number of storeys. Changes in the earthquake behavior of buildings were evaluated according to the number of storeys, the projection ratios and the symmetry conditions of each model. The analysis of each structural irregularity resulted in many findings, which were then assessed. The study demonstrates that the square model delivers the best earthquake performance owing to its regular plan geometry.

• The korean journal of orthodontics
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• v.42 no.5
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• pp.255-262
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• 2012

Objective: We aimed to compare the retention characteristics of Essix and Hawley retainers. Methods: Adolescents undergoing fixed appliance treatment at 2 centers were recruited for this study. Twenty-two patients (16 women and 6 men) wore Essix retainers (Essix group) while 20 (14 women and 6 men) wore Hawley retainers (Hawley group). The mean retention time was 1 year, and the mean follow-up recall time for both groups was 2 years. Two qualified dental examiners evaluated the blind patient data. Maxillary and mandibular dental casts and lateral cephalograms were analyzed at 4 stages: pretreatment (T1), post-treatment (T2), post-retention (T3), and follow-up (T4). Results: The results revealed that Essix appliances were more efficient in retaining the anterior teeth in the mandible during a 1-year retention period. The irregularity index increased in both arches in both groups after a 2-year post-retention period. The mandibular arch lengths increased during treatment and tended to return to their original value after retention in both groups; however, these changes were statistically significant only in the Hawley group. Cephalometric variables did not show any significant differences. Conclusions: The retention characteristics of both Essix and Hawley retainers are similar.

• Korean Parent-Child Health Journal
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• v.17 no.1
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• pp.1-7
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• 2014

Purpose: The research was to identify menstrual regularity & mental health-related factors on unmarried women of childbearing age and provide a raw material in terms of setting up health policy. Methods: The KNHANE V-3 (The Fifth Korea National Health and Nutrition Examination Survey) was used and implemented through spss 18.0. Results: In general characteristics, there wasn't any remarkable difference between 20s and 30s. Looking further Mental health-related factors, stress was higher in 30s (p=.010). In 30s of irregularity mensutration women, it was accounted for 12.5% over than 3months experienced. General characteristics varied by menstrual regularity were age (p=.044), education level (p=.035) and in terms of mental health-related factors, they were stress (p=.044), sleeping time (p=.039). Multiple regression analysis was carried out to identify how influential these factors are on menstrual regularity. As a result, age, education level, sleeping time & stress was the most influence factors. Conclusion: The research had some limitations to specify and approach the feature of target in depth through KNHANE V-3. Thus, if the basic analysis regarding the menstrual problem in relation to local society was conducted on the basis of the result of research, it could help developing the promotion of health program and make the application easier.

• The Research Journal of the Costume Culture
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• v.10 no.3
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• pp.270-282
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• 2002

This study was established to understand how Arte Povera has affected the contemporary fashion based on the analyses of its characteristics and may provide a prospective view to predict style of future fashions. The results were as follows : 1) “The poverty” shows such characteristics as patch work, intentional mismatch, and tendency to prefer slightly used style. This meaning can be explained as direct expression from a sense of alienation, against to consumer economy, and dual-expression between poverty and wealth. 2) “Anti-formativeness” can be described for misinterpretations of creation, arrangement, and informal silhouette due to distortion of the human body. This expression includes such meanings as against to traditionalism, ignorance of rationality, and disorganization of the concepts between the beauty and the ugly. 3) “Naturalism” indicates as characteristics of use of natural materials and primitive expression. This expression could be generated from adaptation to the nature and desire toward uncivilized society due to skepticism about modern society. 4) “Symbolism” shows such expressions as an isolated feeling from society, and metaphoric sense from specific situations because there are too many applications of imported materials. This tendency can be also explained with the creations of spaces for opened concepts through disorganizations of territory, obscurity, and irregularity.

• Journal of the Korean Ceramic Society
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• v.23 no.2
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• pp.13-20
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• 1986

Composite polycrystals including ${\gamma}$-$6Bi_2O_3$.$SiO_2$ crystal which have needlelike regular structure are useful for the high resolution optical devices. For the purpose of obtaining the composite polycrystals described above the melts of eutectic composition in the three eutectic systems including $6Bi_2O_3$.$SiO_2$ composition were unidirectionally solidified at a rate of 0.05 and 0.25 cm/h under a thermal gradient of 10$0^{\circ}C$/m. Composite polycrystals of relatively regular structure in which needlelike ${\gamma}$-$6Bi_2O_3$.$SiO_2$ crystals were arrayed in parallel with $2Bi_2O_3$.$B_2O_3$ crystal matrix were obtained when the eutectic melt of $6Bi_2O_3$.$SiO_2 -2Bi_2O_3$.$B_2O_3$ system was solidified at a rate of 0.25 cm/h. Partial structural irregularity however was found in the obtained composite polycrystals.

• Preventive Nutrition and Food Science
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• v.7 no.4
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• pp.442-446
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• 2002

Differences in dietary habits between Korean smokers and non-smokers were investigated using information obtained from 7,370 adults, aged 20 years and older who participated in the 1998 Korean National Health and Nutrition Sulvey. Dietary habit data including: skipping of meals, meal regularity, meal volume, snacking habits, removing fatty portions before eating foods, and dietary supplement intake were collected using a structured questionnaire by interview. Individual smoking data was also collected by interview as part of the health behavior survey. A Chi-square test was used to test the association between the dietary habits and smoking. 66.9% of the men were smokers (daily current or occasional current), while only 6.7% of women smoked. On average, 34.7% of the subjects were smokers. Smokers were more likely than nonsmokers to engage in the following dietary habits considered unhealthy: skipping breakfast, meal irregularity, large dinners, small breakfasts, frequently eating out, and eating food without removing the fatty portion. Therefore, Korean smokers should be provided education to assist them in making healthy dietary choices such as: eating regular meals, small dinners, and removing fatty Portion of foods. The survey also revealed that a substantial percentage (about 20%) of the subjects were taking some kind of dietary supplement, regardless of smoking status. It is, therefore, alto necessary to inform the general public that a balanced diet is the ideal way to obtain nutrients for optimal health.

• Progress in Medical Physics
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• v.19 no.2
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• pp.113-119
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• 2008

In this study, we have estimated error of calculation results for 5-type RTP systems and investigated a toleration for error of the RTPs referenced from the evaluation items of AAPM Report-62. For this study, we have introduced the concept of 'normal dose rate(NDR)' and compared the results of experiment and calculation from RTPs at the same reference level. The results from all RTPs were satisfied at various field shapes and heterogeneous phantom materials except the surface irregularity.

• The Journal of Korean Medicine
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• v.35 no.2
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• pp.28-33
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• 2014

Background: Samul-tang (Si-Wu-Tang, SMT) is a traditional herbal formula, which has been widely used to treat various diseases such as menstrual irregularity, bleeding and leucorrhea. Although many studies have investigated the pharmacological properties of SMT, its toxicity information has not yet been fully elucidated. Methods: Five Sprague Dawley (SD) rats of each sex were given a single dose (5000 mg/kg) of SMT by gavage; control rats received the vehicle only. After the single administration, mortality, clinical signs, body weight changes and gross findings were monitored for 15 days in accordance with Good Laboratory Practice (GLP) principles. Results: In a single oral dose toxicity study, there was no adverse effect on mortality, clinical sign, body weight change or gross finding in any treatment group. Conclusions: The results indicate that SMT did not induce toxic effects at a dose level up to 5000 mg/kg in rats and its median lethal dose ($LD_{50}$) was considered to be over 5000 mg/kg/day body weight for both genders.