• International Journal of Highway Engineering
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• v.11 no.3
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• pp.41-49
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• 2009

Cement concrete pavement has become more common in Korean highway systems. However, as its service period increases, there are some technical problems occurs and no clear solution is available primarily due to the lack of active researches. This research, hence, aims to develop a new mix proportion that may provide better strength and durability with extended service life. Based on a variety of literature reviews, the experimental variables were determined as unit cement content, S/a ratio and W/C ratio. From the experimental works, it is recommended to increase the unit cement content up to 375kg/$m^3$, 400kg/$m^3$ and 425kg/$m^3$. The target slump and air content were set 40mm and 5%, respectively. The maximum size of coarse aggregate was decided to be 25mm because of the easiness of supply in the field. The reduction of W/C ratio was necessarily required and decreased to 0.4 which was proven not to cause any mixing problem with the increased unit cement contents along with polycarbon-based high range water reducing agent. In addition, it was known that the S/a ratio could be reduced to 0.34. The lowered S/a might be possible because of the increased cement paste and hence increased cohesiveness and workability.

• International Journal of Highway Engineering
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• v.9 no.4
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• pp.83-92
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• 2007

In 2004, the number of traffic crashes and deaths in Korea are 220,755 and 6,563, respectively. Korea Road Traffic Safety Authority reported that the number of traffic accidents occupies over 25% out of total accidents, and found that traffic crash probability is extremely high at intersections since intersections have various traffic conflict points. A Safety study using Traffic Conflict Technique is much more useful than a study using reported traffic accident data. Existing traffic conflict research hardly considered conflict severity occurring at intersections. So, the study developed new criteria considering conflict severity. Analytic methods precisely detecting crashing points using field surveying data, and applied an application of our new criteria. Opposing left-turn conflict criteria was devided by three groups(high severe conflict, middle severe conflict, and less severe conflict) based on conflict boundary by means of a standard vehicle length. After analyzing field surveying data(3hours), we found totally 41 opposing left-turn conflicts. 3 cases are high severe conflict, and another 10 cases are middle severe conflicts, and the other cases are less severe. Studies related in conflict severity are considerably important to evaluate intersection's detailed safety index, and existing studies(purely conflict counting does not consider severity) have a limitation to clearly determine the level of safety of intersections for an application.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.7 no.4
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• pp.36-48
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• 2008

Variable Message Signs(VMS) is one of the important subsystems of Intelligent Transportation Systems (ITS), which is useful for providing drivers with real-time information on traffic, roadway or weather conditions. In order to maximize the effectiveness of the VMS system, it is required to reflect drivers's preference on designing and operating the system. In this context, this study was conducted to develop strategies to deliver the messages in an efficient manner while many other previous studies focused primarily on the contents of the messages, from drivers's perspectives. Drivers's preference on message expression formats and message display orders were investigated through image analysis in the perspectives of a total of 40 subjects. With respect to message expression formats, drivers preferred Gulim or Dodum in font style, middle arrangement of the letters, pictogram combination as opposed to letters only, blank time less than 0.5 sec, appearing message in animation effect, messages in single phase, non-flashing message. In the matter of message display orders, drivers preferred to obtain link or traffic information in the lust place. Then, they desired to be informed of roadway condition and instructions or recommendations for drivers to cope with unexpected events among various messages for traffic condition.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.18 no.3
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• pp.34-45
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• 2019

Based on the analysis of congestion conditions in small cities with a population of less than 500,000 in Chungcheong Province, this study conducted a feasibility study on the scope of congestion improvement projects. Further, traffic congestion management standards were further established by analyzing LOS as well as the speed of traffic presented by congestion criteria in the existing Project. According to the analysis according to the congestion management standard LOS suggested in this study, Asan city has the most major number of highways where LOS E occurs for more than 3 hours, followed by Sejong City and Gongju City. In addition, when comparing the ratio of the busy main roads according to the frequency of LOS E by city size, it was analyzed that the ratio and extension of the busy highways relative to the overall extension of the large Chungcheong area are similar to the ratio in small cities in the Chungcheong region. Therefore, traffic congestion occurred in small cities and the feasibility of the improvement project was revealed.

• Korean Journal of Culture and Social Issue
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• v.8 no.1
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• pp.17-40
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• 2002

The purpose of this study is to investigate the differences in the traffic environments and driving behaviors in 5 regions of Korea. Data were collected through the survey research from 1387 passenger car drivers in 14 locations in Korea. The main findings of this research are as followings: First of all, There were significant differences in traffic environment factors(road topography, construction, road & safety facilities, pedestrian behaviors, surrounding drivers) among 5 regional areas. When we examined drivers factors, there were significant differences among 5 metropolitan areas on wearing seat belt, most of constructions related to drink driving, speed-limit violation. There were many differences in driving habits, intentions, behaviors including wearing seat belt, driving after drinking according to metropolitan area, and also in case of speed-limit violation and careless driving behavior. These results suggested that there are many differences in traffic environments and driver's behaviors among regional areas. These result suggests that traffic safety policy and practice should be prepared based upon the peculiarities of regional area. We discussed these resulte in terms of the regional traffic policy and the suggestions for future studies were added.

• The Journal of the Korea Contents Association
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• v.20 no.11
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• pp.581-589
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• 2020

This study aims to examine the effects of adjustment factors to college life on the work values of public health major students. We sampled 530 undergraduate students majoring in public health administration and engineering from Kyunggi-do, and analyzed the data using t-test, correlation and regression methods obtained from SPSS Win 21.0 software. We found that (1) a student's intrinsic work value is positively related to their adjustment to college life factors but extrinsic work value is positively related to 'professor-student interaction', 'college life satisfaction' and 'expectation for the service college'; (2) 'social integration', 'professor-student interaction' and 'expectation for the service college' influenced to intrinsic work value; (3) 'career identity', 'family support', and 'college life satisfaction' influenced to extrinsic work value. Based on the results of this study, that the improvement of adjustment to college life factors influence on the work values were discussed.

• The Journal of the Korea Contents Association
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• v.7 no.1
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• pp.184-189
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• 2007

In case of Korea Social cost by road traffic accident came to about 15 trillion per year and to 2.15% of GDP, a day about 20 person death to traffic accident and those damage scale reach out about 7 billions. Concretely, according to OECD traffic accident comparison on July 2005 (2003 statistical analysis), in korea, 7,212 Person were dead. This describe that the sacrifice numbers of traffic accident is 26 level of OECD 26 countries, the dead of traffic accident on children 100,000 persons is 25 level of OECD 25 countries. It is contrast to other developed countries. In the meantime, korea government executed various traffic policies to reduce traffic accident and depending on those policies, even if, there were epochal progressive phenomena the concerns of citizens which felt on franc accident is very deficient. On this research, traffic accident state of taking place of Gowangju.Jeonnam province was analysed depend on jeonnam province police station materials and want to suggest appropriate traffic safty counterplan propose. This subject was analysed traffic accident according the death with analysing per month, day, hour, and suggest counterplan depending on traffic accident analysis result on 2004. 2005 years.

• Journal of The Korean Association For Science Education
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• v.23 no.1
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• pp.75-85
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• 2003

We have developed of a criterion that would help to select and develop performance assessments in science education. There are six categories of a criterion: Fidelity, satisfaction, content validity, fairness & suitability, reliability & objectivity, and usability. There are the total of 25 sub-categories under the six categories. Five science educators evaluated the validity of the criterion. For reliability of the criterion, Kendall's tau-b was used. Eight science educators and elementary teachers evaluated three performance assessment tasks for the correspondence of the criterion. This study also discuss the implications of this criterion as well.

• Research in Community and Public Health Nursing
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• v.7 no.1
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• pp.170-177
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• 1996

신체의 활력을 측정하는 혈압은 다른 어느 측정치보다 변동이 심하고 정상적으로 변할 수 있는 생리적 현상이어서 정확하게 측정하기란 쉽지 않다. 1mmHg 차이의 혈압일지라도, 특히 큰 집단일 경우, 연구목적에서 그 결과를 크게 왜곡 시킬 수 있다. (Wright & dore, 1970). 혈압 측정에는 직접적 방법과 간접적 방법이 있다. 이 중 간접적 방법은 임상분야와 연구분야에서 실제로 넓게 사용되고 있을 분만 아니라 신체로의 직접적 침투하는 방법도 아니고 가격 또한 비싸지 않다. 그러나, 간접적 측정 방법은 혈압에 영향을 끼치는 많은 요인들인 관찰자 편견, 확장기음의 청취음 선택, 관찰자와 환자 사이의 상호관계 때문에 방법론적으로 문제제기가 되기도 한다. 이런 요인을 최소화하기 위하여 가장 타당도가 높은 측정도구의 선택이 필요하다. 도시지역의(Ease Baltimore) 고혈압을 가진 젊은 흑인 남성(연령별/성별/종속별/거주지역) 중 수축기 혈압이 140mmHg 이고 확장기 혈압이 90mmHg인 사람, 또는 확장기 혈압이 90mmHg인 사람, 또는 혈압하강제를 먹고 있는 사람 200명을 대상으로 훈련받은 community health worker(CHW)에 의해 Random-Zero Sphygmdmanometer(RZS)와 Digit Automatic Device(DAD)로 혈압을 측정하게 하였다. 이 중 36명을 무작위 추출하여 regular Mercury Sphygmdmanometer (RMS)로 혈압을 측정하게 했다. Bland 와 Altman에 의해 제기된 두측정값의 차이에 대한 scattergram(일치도 검증법)과 AAMI(Association for the Advancement of Medical Instrument) 기준, BHS 기준, Central Tendency와 숫자선호도로 검증되었다. AAMI와 BHS 기준에 의하면 확장기 혈압에서 RZS와 DAD의 일치도와 평균을 중심으로 더 넓게 퍼져있어 낮은 일치도를 보였으며 또 DAD와 RMS의 혈압치는 숫자 선호도를 볼 수 있는데 특히 RMS는 더 뚜렷하게 나타났는데 확장기 혈압의 최빈치(30.6)는 100mmHg이었다. 혈압치들이 가장 가까이 "0"점으로 치우쳐져 있었다. RZS의 Central tendency는 DAD와 RMS보다 뚜렷하였다. 결론적으로 RZS는 이 연구목적으로 가장 적절함을 보여준다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.1
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• pp.128-134
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• 2013

The purpose of this study wat to investigate relationships of learning motivation and self-efficacy according to participation in a motivational program for university freshman studying physical education. A total of 66 university freshman participated in the current study and divided into experimental group and control group. Questionnaires were distributed before and after motivational program. Statistical methods used in this study were descriptive analysis, paired t-test, ANOVA, and ANCOVA. The results showed the following. First, There was a significant difference in the external motivation variable of learning motivation of the experimental group. Second, the experimental group showed a statistical difference between pretest and posttest in the confidence variable of self-efficacy. positive attitude influenced on leisure satisfaction.