• Transportation Technology and Policy
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• v.7 no.5
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• pp.91-98
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• 2010

• Journal of the Korean Ceramic Society
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• v.53 no.4
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• pp.411-416
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• 2016

Benzothienobenzothiophene ($C_8-BTBT$) is a soluble organic small molecule material with high crystallinity resulting from its strong self-organizing properties. In addition, the high mobility and easy fabrication of $C_8-BTBT$ make it very attractive in terms of organic thin-film transistors. In this work, we made $C_8-BTBT$ thin films by using the zone-casting method; we also used an organic solvent to treat the devices with solvent vapor annealing to improve the electrical properties. As a result, we confirmed improved mobility, threshold voltage, and subthreshold swing after solvent vapor annealing. To prove the effect of solvent vapor annealing, we used the simultaneous extraction model to extract the contact resistance from the current-voltage curve. We confirmed that the electrical properties improved with decreasing contact resistance.

• The Korean Journal of Food And Nutrition
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• v.25 no.2
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• pp.398-406
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• 2012

The acid value of the oil extracted from the three kinds of 15 fried foods ranged from 0.89 to 3.92, the peroxide value ranged 10.0~57.14 meg/kg. Among the samples, popcorn chicken contained the highest crude fat content, showing $6.64{\pm}0.26(%)$, while the french-fries showed $2.87{\pm}0.31(%)$, which was the lowest. The content of the trans fatty acid per 100 g of the foods were; the fried foods: 0.02~0.06 g. The french-fries contained the lowest saturated fatty acid per 100 g of the foods, showing 0.41~1.55 g, while the popcorn chicken showed the highest content, 1.16~3.43 g. The fried foods contained the highest linoleic acid content. Further, fried foods exhibited safe levels of trans fat content. The "School Zone", which sells snacks, candies, chocolates flow, was not detected in the saccharin. Cookies, candies, chocolate was not detected in the tar colors. Aerobic plate count were ranged from 0~4,700 cfu/g in cookies, Salmonella test came out negative.

• Journal of Korean Society of Transportation
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• v.26 no.5
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• pp.29-40
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• 2008

Police agency is indicated that the number of children's traffic accident is tending downwards, however about one child is dead every day due to traffic accident. Major parts of the accidents happen during walking; among the rest, jaywalking is the biggest reason. Many accidents take plate on the road to school or near the home so government legislate children safeguard zone at 1995. According to the legislation, drivers have to reduce speed and there are safety facilities for children at children safeguard zone. This study finds the problems of children safeguard zone and suggest more effective and quantitative method for children safeguard zone. Firstly this study grasps the characters of children's pattern movement and children's traffic accident at children safeguard zone and then divides specific danger factors of children's traffic accident at children safeguard zone. Secondly, each factor is given danger level depending on danger degree and suggests effective method for assignment standard of children safeguard zone using all of these things.

• Journal of Radiation Protection and Research
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• v.41 no.3
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• pp.196-205
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• 2016

Background: The emergency planning zone (EPZ) of the city of Busan is divided into the precautionary actions zone (PAZ) and the urgent protective action planning zone; which have a 5-km radius and a 20-km to 21-km radius from the nuclear power plant site, respectively. In this study, we assumed that a severe accident occurred at Shin-Kori nuclear unit 3 and evaluated the dispersion speed of radiological material at each distance at various wind speeds, and estimated the effective dose equivalent and the evacuation time of PAZ residents with the goal of supporting off-site emergency action planning for the nuclear site. Materials and Methods: The total effective dose equivalent, which shows the effect of released radioactive materials on the residents, was evaluated using the RASCAL 4.2 program. In addition, a survey of 1,036 residents was performed using a standardized questionnaire, and the resident evacuation time according to road and distance was analyzed using the VISSIM 6.0 program. Results and Discussion: According to the results obtained using the VISSIM and RASCAL programs, it would take approximately 80 to 252.2 minutes for permanent residents to move out of the PAZ boundary, 40 to 197.2 minutes for students, 60 to 232.2 minutes for the infirm, such as elderly people and those in a nursing home or hospital, and 30 to 182.2 minutes for those temporarily within the area. Consequently, in the event of any delay in the evacuation, it is estimated that the residents would be exposed to up to $10mSv{\cdot}h^{-1}$ of radiation at the Exclusion Area Boundaries (EAB) boundary and $4-6mSv{\cdot}h^{-1}$ at the PAZ boundary. Conclusion: It was shown that the evacuation time for the residents is adequate in light of the time lapse from the initial moment of a severe accident to the radiation release. However, in order to minimize the evacuation time, it is necessary to maintain a system of close collaboration to avoid traffic congestion and spontaneous evacuation attempts.

• The Journal of the Korea Contents Association
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• v.21 no.11
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• pp.213-223
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• 2021

It is very important to build a safe walking environment for children because children are more likely to be exposed to traffic accidents than adults due to their behavioral and physical characteristics. Therefore, this study analyzed the characteristics of road and transportation safety facilities that affect pedestrian traffic accidents around school zones using spatial poisson regression. The pedestrian-vehicle crash data in Seoul 2016-2018 was provided by the Traffic Accident Analysis System(TAAS). The main analysis results are as follow; First, the more intersections and the higher percentage of neighborhood roads in the school zone, the higher the risk of pedestrian traffic accidents. Second, the pedestrian push button was found to reduce the occurrence of pedestrian traffic accidents. Third, except for the pedestrian push button, none of the transportation safety facilities considered in this study were effective in reducing the risk of pedestrian traffic accidents. On the other hand, if not only the improvement of physical facilities but also non-physical factors such traffic safety education are supported, the effect for reducing traffic pedestrian traffic accidents in the school zone is expected to be further maximized.

• Proceedings of the Korean Geotechical Society Conference
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• 2007.09a
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• pp.481-501
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• 2007

Excessive rainfalls due to climatic changes can trigger an increase in rainfall-induced slope failures that pose real threats to both lives and properties. Many high slopes in residual soils could stand at a steep angle, but failed during or after rainfall. Commonly, these slopes have a deep groundwater table and negative pore-water pressures in the unsaturated zone above the groundwater table contribute to the shear strength of soil and consequently to factor of safety of the slope. Stability assessment of slope under rainfall requires information on rate of rainwater infiltration in the unsaturated zone and the resulting changes in pore-water pressure and shear strength of soil. This paper describes the application of unsaturated soil mechanics principles and theories in the assessment of rainfall effect on stability of slope through proper characterization of soil properties, measurement of negative pore-water pressures, seepage and slope stability analyses involving unsaturated and saturated soils. Factors controlling the rate of changes in factor of safety during rainfall and a preventive method to minimize infiltration are highlighted in this paper.

• Journal of Preventive Medicine and Public Health
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• v.38 no.2
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• pp.163-169
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• 2005

Objectives: Pedestrian traffic injuries have been an important cause of childhood mortality and morbidity for decades. The aim of this study was to describe the epidemiological characteristics of child pedestrian traffic injuries that occurred during 2000 in one metropolitan city and its school-zones, and to determine the factors associated with those accidents. Methods: A cross-sectional study was performed in 2001. Police records were used to identify the cases of pedestrian injury. Children aged between 6 and 15 years, injured during road walking, were included in this study. A direct survey of the environmental factors within the school-zones in study area (n=116) was also performed. Self-administered questionnaires, via mail and telephone surveys, were used to assess the safety education programmes. The schools were divided into two groups according to the occurrence of pedestrian traffic injuries in their school-zone. Results: Pedestrian injuries (n=597) were found to account for 3.2% of all traffic injuries in the subject area. The epidemiological characteristics were not significantly different between genders. There were some significant risk factors within the environmental factors, such as local road (OR: 2.3, 95% CI=1.05-5.35), heavy traffic volume (OR: 2.2, 95% CI=1.00-5.04), poor visibility of speed-limit signs (OR: 2.8, 95% CI=1.25-6.42), no separation of pedestrian routes from cars (OR: 2.6, 95% CI=1.02-6.75) and barriers on the pedestrian routes (OR: 2.2, 95% CI=1.01-5.08). Only one factor, that of education in a safety-park (OR: 0.3, 95% CI=0.09-0.96), was significantly associated in the traffic and pedestrian safety education factors. Conclusion: Significant associations with pedestrian injury risk were identified in some of the modifiable environmental factors than in the educational factors.

• Journal of Information Technology Services
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• v.15 no.4
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• pp.73-83
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• 2016

Pedestrian safety was recently highlighted with a yellow carpet, a yellow-colored pavement material prepared for children waiting for signals for pedestrian crossing, without validation of its efficiency in practice. It was a promising device likely to assist highway safety by stimulating pedestrian to step on the yellow-colored area; it was generally called nudge effects. This paper delivers a study conducted to check the effectiveness of yellow carpet in three different aspects in vehicle driver's perspective by applying the newly introduced information technology (IT) service: Visual Attention Software (VAS). It was assumed that VAS developed by 3M in the United States should be able explain the Korean drivers' visual reaction behaviors since technology embedded in VAS was developed based on and proved by other various international countries and continents in the world. A set of pictures was taken at thirteen different field sites in seven school zone areas in the Seoul metropolitan area before and after the installation of a yellow carpet, respectively. Sets of those pictures were analyzed with VAS, and the results were compared based on the selective safety measures: the likely focusing on standing pedestrians (waiting for a pedestrian's green signal time) affected by its background (yellow-colored pavement) contrasting him or her. The test results from a set of before-and-after comparison analyses showed that the placement of yellow carpet would (1) increase 71% of driver's visual attention on pedestrian crossing areas and (2) change the sequential order of visual attention on that area 2.4 steps ahead. The findings would enhance deployment of such promising efficiency and thus increase children safety in pedestrian crossing. The result was promising to highlight the way to support the changes in conservative traffic safety engineering field by applying the advanced IT services, while much robust research was recommended to overcome the limitation of simplification of this study.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2010.04a
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• pp.84-89
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• 2010

본 연구에서는 공기를 Fresh-water, 화재를 Salt-water로 치환하여 밀도차에 의한 Salt-water 확산의 화재 모사 적용성을 기초적으로 검증한다. 실험은 Zone model과 Field model의 화재해석 결과 나타난 천장부 확산, 와류 발생, 연기층 하락, 연기층과 공기층의 구분 등의 특징을 분석 기준으로 하며 Salt-water에 Tracer를 첨가하여 PIV(Particle Image Velocity) 분석법을 통해 확산현상에 대해 분석하였다. 결과로 Salt-water의 용해도가 높을수록 천장부 확산, 와류 발생, 연기층 하락, 연기층과 공기층의 구분에 있어 실제 화재와 유사한 것으로 판단되며 최소 15.0%이상의 용해도에서 이와 같은 현상이 뚜렷해지는 것으로 분석되었다. 본 연구를 통해 축소모형 화재 모사시 발열 상태가 아닌 다른 방법으로의 모사가 가능한 것이 증명하였다.