• 한국안전학회지
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• 제27권3호
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• pp.141-146
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• 2012

This study deals with the accident model using panel data which are composed of time series data of 2005 through 2007 and cross sectional data of link sections in Cheongju. Panel data are repeatedly collected over time from the same sample. The purpose of the study is to develop the traffic accident model using the above panel data. In pursuing the above, this study gives particular attentions to deriving the optimal models among various models including TSCSREG (Time Series Cross Section Regression). The main results are as follows. First, 8 panel data models which explained the various effects of accidents were developed. Second, $R^2$ values of fixed effect models were analyzed to be higher than those of random effect models. Finally, such the variables as the sum of the number of crosswalk on intersections and sum of the number of intersections were analyzed to be positive to the accidents.

• 한국도로학회논문집
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• 제20권2호
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• pp.119-126
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• 2018

PURPOSES : The purpose of this study is to develop a crash prediction model at signalized intersections, which can capture the randomness and uncertainty of traffic accident forecasting in order to provide more precise results. METHODS : The authors propose a random parameter (RP) approach to overcome the limitation of the Count model that cannot consider the heterogeneity of the assigned locations or road sections. For the model's development, 55 intersections located in the Daejeon metropolitan area were selected as the scope of the study, and panel data such as the number of crashes, traffic volume, and intersection geometry at each intersection were collected for the analysis. RESULTS : Based on the results of the RP negative binomial crash prediction model developed in this study, it was found that the independent variables such as the log form of average annual traffic volume, presence or absence of left-turn lanes on major roads, presence or absence of right-turn lanes on minor roads, and the number of crosswalks were statistically significant random parameters, and this showed that the variables have a heterogeneous influence on individual intersections. CONCLUSIONS : It was found that the RP model had a better fit to the data than the fixed parameters (FP) model since the RP model reflects the heterogeneity of the individual observations and captures the inconsistent and biased effects.

• 대한교통학회지
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• 제23권7호
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• pp.17-33
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• 2005

도로설계속도는 해당도로 규격을 결정하는 매우 중요한 설계요소이다. 설계속도 결정시 개통후 차량 주행속도를 예측하여 상관성이 높도록 계획해야 하는데, 기존 일반국도 주행속도 예측 모형은 설계속도에 따른 기하구조 요인만을 고려하여 도로의 주변환경을 고려하지 못하는 한계가 있다. 주변환경을 충분히 고려하지 않을 경우 과도한 공사비 지출과 지나친 환경 파괴우려가 있다. 따라서 본 연구에서는 도로 주변환경요소를 고려하는 주행속도 예측모형식의 정립을 시도했고, 연구결과는 다음과 같다. 첫째, 우리나라 일반국도의 지형 및 지역 요소를 운전자의 시각 특성과 GIS 프로그램을 활용하여 정의하였다. 둘째, 이렇게 구축한 지형 및 지역 특성이 차량의 주행속도에 미치는 영향을 살펴보았다. 그 결과, 지형 및 지역 별로 95% 신뢰도에서 속도차이가 있는 것으로 판단되었다. 섯째, 일반선형 모형(GLM)을 통하여 기하구조 요인과 지형 및 지역 요인을 모두 고려한 예측 모형식을 수립해 보았는데, R-Square가 양방향 2차로는 0.67, 양방향 4차로가 0.85로 나타났다. 끝으로 본 연구에서 개발한 모형을 바탕으로 지형 및 지역요소를 감안한 적정 도로 설계속도 범위를 제시했다. 이 방법론에 따라 산출된 관련 설계속도 범위는 일반국도에 대해 적용할 수 있지만, 지방도등 타 도로에 대해서는 직접 적용하기 곤란하다.

• 한국공간정보시스템학회:학술대회논문집
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• 한국공간정보시스템학회 2005년도 추계학술대회
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• pp.257-270
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• 2005

Many studies states that improperly uprising of infrastructure may cause leading the forest degradation and canopy reduction in many tropical forest of Asian countries. Other studies revealed that habitat destruction and fragmentation, edge effects, exotic species invasions, pollution are provoked by roads. Similarly, environmental effects of road construction in forests are problematic. Similarly, many researches have been indicated that roads have a far greater impact on forests than simply allowing greater access for human use. Moreover, people using river as means of transportation hence illegal logging and felling cause canopy depletion in many countries. Therefore, it is important to comprehend the study about spatial relation of road, river and suburb followed by temporal change of forest canopy phenomena. This study also tried to examine the effect of road, river and suburb in forest canopy density change of Terai forest of Nepal from you 1988 to 2001. So, Landsat TM88, 92 and 001 and FCD (Forest Canopy Density) mapper were used to perform the spatial .elation of canopy density change. ILWIS (Integrated Land and Water Information System) which is GIS software and compatible with remote sensing data was used to execute analysis and visualize the results. Study found that influence of distance to suburb and river had statistically significance influenced in canopy change. Though road also influenced canopy density much but didn't show a statistical relation. It can be concluded from this research that understanding of spatial relation of factors respect with canopy change is quite complex phenomena unless detail analysis of surrounding environment. Hence, it is better to carry out comprehensive analysis with other additional factors such as biophysical, anthropogenic, social, and institutional factors for proper approach of their effect on canopy change.

• 한국도로학회논문집
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• 제11권4호
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• pp.49-58
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• 2009

현행 우리나라의 일조규정은 공동주택 및 일반 건축물을 중심으로 되어있기 때문에 도로 및 고가 구조물의 특성을 충분히 반영하지 못하고 있다. 또한, 공동주택간의 인동간격 및 인동간격이 미치는 다양한 영향에 대한 연구는 많이 이루어지고 있으나, 도로 및 고가 구조물과 주거지역과의 이격거리 및 구조물에 의해 발생되는 일조장애들의 환경적인 요소와 그에 따른 인자에 관한 연구는 미비하다. 따라서 본 연구에서는 도로 및 고가 구조물 중 주거지역과 인접해 있는 고가구조물을 중심으로 일조환경을 검토하여, 현재 사용되는 이격거리의 적정성 여부를 검토해보고, 구조물의 방위각에 따른 방향별 특성을 분석하였다. 구조물의 특성에 따른 일영거리를 통해 높이에 따른 이격거리비율을 산정하여, 향후 건설시 발생되는 일조장애를 최소화 하기위하여 구조물에 관한 제도 정비의 필요성과 최소 이격거리산정에 필요한 기초자료를 제시하는데 주목적을 두었다.

• 한국환경보건학회지
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• 제35권3호
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• pp.143-152
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• 2009

Indoor air quality at classrooms is of special concern since students are susceptible and indoor air problems can be so subtle that it does not always produce easily recognizable health effects. The main objectives of the study were to investigate the time-activity pattern of school students, to determine the sources of poor indoor air quality in schools, and to demonstrate how indoor air quality in schools causes adverse health effects such as headache, upper airway irritation, fatigue, and lethargy. Recent articles ranging from 1987-2009 related to school indoor air quality were systematically reviewed. Building-associated health effects can increase student absences from school and degrade the performance of children while in school. The reduced ventilation rate was associated with a decreased ability to concentrate along with increased adverse health symptoms. There was an association between residential proximity to busy roads and a variety of adverse respiratory health outcomes in children. Consequently, the current findings suggest the need for control strategy for school indoor air pollutants with multidisciplinary approach methods because Korea has no other natural resources except manpower especially.

• 패션비즈니스
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• 제10권3호
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• pp.129-142
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• 2006

This research chose 135 environmental cleaners in Busan Metropolitan City as subjects. First, the reality of wearing their safety jackets was investigated. Next, visual evaluation of the reflexive function of the current safety jackets was made. Then, based on the above results and the subsequent improvement proposal, the final product, the research costume, was made. 1. Based on the investigation of the wearing reality of safety jackets and the visual evaluation results of the reflexive function, an improvement proposal was made. As cleaners are usually seen sidewise on the roads and lateral luminosity is rather low, this aspect was compensated on the part of a jacket. Also, the reflexive belt used the diagram of ${\Delta}$ to improve visual effects. 2. As the lower body held the accident frequency of 45.0%, the sides of pants had the reflexive belt to increase visibility. 3. In consideration of the mutual effects between the background cloth and general reflexive width, the same width (5cm) of the reflexive belt as that of Type A was adopted.

• Journal of Ecology and Environment
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• 제32권2호
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• pp.83-86
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• 2009

We conducted a landscape analysis to investigate the possibility of adverse effects of anthropogenic light sources, such as roads and residential buildings, on Lethocerus deyrollei on Jeju Island, Wetlands inhabited by L. deyrollei had fewer anthropogenic structures within a 3 km radius that had the potential to produce artificial light at night than wetlands not inhabited by L. deyrollei, In particular, the presence of artificial lights within a 1 km radius appears to reduce the probability of inhabitation by L. deyrollei, Our results suggest that artificial light sources may be critical determinants of L. deyrollei inhabitation patterns in a landscape, and that habitats that have a buffer area of at least 600$\sim$700 m radius free from residential buildings are the most appropriate habitats for L. deyrollei.

• 한국도로학회논문집
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• 제19권5호
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• pp.153-162
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• 2017

PURPOSES : This study was conducted to analyze the effects arising from extending the duration of nighttime road construction on improving road quality and durability. METHODS : Most previous studies estimating the social cost of various construction conditions did not consider road pavement cooling time as a factor in improving road pavement quality. This study investigated the feasibility of achieving higher road quality and durability by extending the duration of nighttime road construction time extension. For this investigation, the effects of such an extension on traffic conditions were analyzed based on micro-simulation studies and scenario-based cost-benefit analyses, using factors including traffic volume, delay, construction cost, and road pavement cooling time. RESULTS : The results of the traffic simulation studies and cost-benefit analyses indicate that the current road construction method that emphasizes completing nighttime road construction by 6 a.m. reduces pavement life while causing relatively little traffic delay. If the night construction time is instead extended to 2 p.m., road pavement lifetime is increased, reducing road re-construction cost. These savings are greater than the cost of congestion arising from extending the duration of nighttime construction. CONCLUSIONS : The current nighttime construction durations need to be extended in order to efficiently manage roads and reduce road management costs.

• Journal of Preventive Medicine and Public Health
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• 제50권2호
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• pp.83-90
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• 2017

Objectives: The aim of this study was to model the avoidable burden of the risk factors of road traffic crashes in Iran and to prioritize interventions to reduce that burden. Methods: The prevalence and the effect size of the risk factors were obtained from data documented by the traffic police of Iran in 2013. The effect size was estimated using an ordinal regression model. The potential impact fraction index was applied to calculate the avoidable burden in order to prioritize interventions. This index was calculated for theoretical, plausible, and feasible minimum risk level scenarios. The joint effects of the risk factors were then estimated for all the scenarios. Results: The highest avoidable burdens in the theoretical, plausible, and feasible minimum risk level scenarios for the non-use of child restraints on urban roads were 52.25, 28.63, and 46.67, respectively. In contrast, the value of this index for speeding was 76.24, 37.00, and 62.23, respectively, for rural roads. Conclusions: On the basis of the different scenarios considered in this research, we suggest focusing on future interventions to decrease the prevalence of speeding, the non-use of child restraints, the use of cell phones while driving, and helmet disuse, and the laws related to these items should be considered seriously.