Distractive marking, as conceptualized by Abbott H. Thayer, refers to diminutive patterns of contrasting colors on an animal’s body. Thayer hypothesized that these patterns augment camouflage by diverting predatory focus from the outline of the prey, however, the evidence was insufficient. In this study, we verified the hypothesis that the presence of distractive markings confers a survival advantage under specific conditions. Specifically, the experiment aimed to ascertain whether the existence of lichens on trees hinders the visual detection of prey, given that lichens resemble distractive markings. The experimental design involved human subjects as predators and artificial moth images on a monitor as prey. The survival of moths with and without distractive markings was compared, also considering the influence of the presence of lichens in the background. As an analysis result, the survival likelihood of moths was statistically significantly hindered when the distractive marking was present. This result contradicts Thayer‘s hypothesis and implies the presence of a function distinct other than the enhancement of camouflage.

PURPOSES : The purpose of this study is to evaluate the effectiveness of self-luminescent road markings using driving simulation. METHODS : In this study, a driving simulation was conducted to evaluate the effectiveness of self-luminescent road markings. The details of this study are as follows. Highway sections were categorized as tunnels, tunnel approaches, bridges, merging areas, mainlines, and curbs. The luminance of the existing road markings was collected through field measurements. The luminance of the self-luminescent road markings was collected through experimental measurements. The luminance of the road markings is converted into a brightness ratio to be applied to the driving simulation. Road facilities at night were visualized during the driving simulation. Driving simulation was tested by 30 participants. Each participant rated the visibility perception of both the road markings ahead of 90 m with a 5-point scale. The log data generated from the driving simulation tests were analyzed. RESULTS : The luminance of the existing road markings and self-luminescent road markings was measured. The luminance of the existing and lab-based road markings was converted into a brightness ratio. The road facilities of highway sections were investigated for driving simulations. The driving simulation was tested by 30 participants. Visibility perception ratings and log data from the driving simulation were analyzed. The average of visibility point increased from 1.01 to 4.63 when self-luminescent road markings were added to the existing road markings. The average speed also increased when self-luminescent road markings were added to existing road markings. CONCLUSIONS : In conclusion, self-luminescent road markings can improve the visibility of road markings and driving speed, particularly in highway sections where driving speed decreases owing to low visibility.

PURPOSES : The retroreflectivity of pavement markings for road safety was evaluated. METHODS : Field tests of pavement markings, which are characters, symbols, crosswalks, and stop lines, but do not include line markings, were conducted using a portable retroreflectometer with the purpose of evaluating the retroreflectivity according to the type of pavement markings and roads. Furthermore, changes in retroreflectivity due to wheel passing and wet conditions were evaluated. Here, 192 test points for evaluating the retroreflectivity of pavement markings, 5 test points for evaluating reductions in retroreflectivity during conditions of wetness, and 28 test points for checking variability due to type of testing device were selected on major and minor arterial roads in Seoul. RESULTS : The average retroreflectivity of pavement markings measured in this study was 115.7 (mcd/m2·lux), which is lower than the minimum retroreflectivity required six months after installation but higher than the minimum remarking retroreflectivity required by Seoul city. The retroreflectivity of pavement markings measured on minor arterial roads was 69.1% of that on major arterial roads. The average retroreflectivity of pavement markings was reduced to 43.1% by wheel passing, which is below the remarking criterion. The average retroreflectivity measured on wet pavement markings was 43.7 (mcd/m2·lux), which is a ninth of that under dry conditions. The test results showed that retroreflectivity in the rain was much lower than the required value in the case of rain, which is 175 mcd/m2·lux, as issued by Seoul city. Compared with mobile retroreflectometers, a portable retroreflectometer produced 17% higher retroreflectivity based on the results of 28 test points. CONCLUSIONS : Based on the field tests, the retroreflectivity of pavement markings, i.e., characters, symbols, crosswalks, and stop lines, was higher than the average remarking criterion. However, the retroreflectivities of pavement markings passed by the wheel or in rain were lower than the remarking criteria. Considering that the remarking criteria in Seoul city are higher than those in Europe and the test results in this study indicate much lower values than those required in Seoul, further study is necessary to be able to properly modify the criteria for retroreflectivity.

PURPOSES: This study analyzes feasibility for application white pavement markings in the roadways with median barrier. METHODS : By reviewing numerous relevant laws, standards, and operational cases, the white pavement markings' excellence was demonstrated. Driver’s behavior was analyzed through a virtual driving experiment using driving simulator and field tests. RESULTS: First, white pavement markings are superior to yellow pavement markings in terms of visibility, economics, and safety. Second, as a result of virtual driving experiment, the color of line in the roadway with median barrier didn’t affect the driver’s behavior such as the average vehicle speed, the distance bias in the lane and the separation distance from the centerline. Third, field test demonstrated that the driver tended to recognize the median barrier as an obstacle. In addition, the central driving ratio in the lane was increased due to improving the visibility of line at night in case of the white pavement markings. CONCLUSIONS : The application of white pavement markings in the roadways with median barrier can enhance traffic safety by improving the visibility of line at night.

PURPOSES: In this study, we evaluated changes in the retroreflectivity and luminance of phosphorescent road line markings with changes in glass beads and line marking thickness. METHODS : The color of line markings affects their retroreflectivity. Using a chromaticity test, we conducted the analysis of whether phosphorescent road line markings adhered to the「 KS M 6080」standard. Then, we measured the dry retroreflectivity and wet retroreflectivity for various glass bead refractive indices. We conducted wet retroreflectivity test using the EN 1436 standard as the basis. We also conducted luminance tests for different glass bead refractive indices and line marking thicknesses. RESULTS : 1. Phosphorescent road line markings specimens satisfied the 「KS M 6080」standard. 2. In dry retroreflectivity test, phosphorescent road line markings sprayed with glass beads satisfied the national police agency standard (240 mcd/(m2₩Lux)). Wet retroreflectivity test results showed that except for one type of No.1 glass beads, phosphorescent road line markings specimens sprayed with glass beads of one type of No.3 and two types of No.1 satisfied the national police agency standard (100 mcd/(m2₩Lux)). 3. Phosphorescent road line markings had higher retroreflectivity than non-phosphorescent road line markings in the dry condition. 4. Phosphorescent road line markings sprayed with glass beads demonstrated improved luminance. Luminance increased with higher glass bead refractive index and with increased line marking thickness. However, when the thickness crossed a certain threshold, phosphorescence ceased to increase; this is a characteristic of the phosphorescence phenomenon. CONCLUSIONS : Visibility across short distances can be ensured when phosphorescent road line markings are sprayed with glass beads, because of the retroreflection phenomenon. It is also possible to ensure far visibility using phosphorescent road line markings.

PURPOSES: Speeding is often the primary contributor to fatal crashes. Surprisingly, driving behaviors are indirectly affected by personal factors such as law-abidance, risk sensitivity, and situational adaptability. This research aims to verify the effectiveness of pavement markings at reducing the speeds of high-risk drivers. The purpose of this study is to establish how drivers (including law-abiding or law-breaking, high-risk or low-risk) react to different pavement markings in a driving simulator. METHODS: The five different pavement markings were selected from markings used in other nations. The forty-two drivers were then surveyed, via questionnaires, and placed into the corresponding groups. Finally, statistical analysis was conducted to determine the extent of speed reduction for each pavement marking. RESULTS: Higher speeds were linked to the high-risk drivers. Furthermore, after analysis of the mean difference of average speeds by pavement marking, it was determined that Dragon's Teeth had the greatest speed reducing effect on these drivers. CONCLUSIONS: Perceptual countermeasures are unlikely to strongly affect high-risk drivers' perception of speed on the curves. This statistically demonstrates that Dragon's Teeth have a subtle effect on reducing speeds in the driving simulator. This study's significance lies in the improved understanding of high-risk drivers in terms of road facilities. It approaches the effects of various patterns of pavement markings for high-risk drivers.

도로표지용 도료의 품질기준은 KS M 6080의 품질기준을 만족하는 제품들의 경우에도 시공 후 일정기간이 경과한 후에는 도료 자체의 부착력 문제로 교통량 증가에 따른 자동차 차륜에 의한 도료 자체의 마모 손실에 의하여 재귀반사 기능을 부여하는 유리알의 마모 및 탈리로 시인성이 급격히 저하되고 있다. 이에 따른 야간 교통 사고율 증가와 동시에 추가 교통 안전을 위한 부가 보완시공으로 안전시설 제비용이 직접비용으로 유발되고 있으며, 직접비용보다 추가공사로 인한 교통체증으로 사회간접 비용이 증가되고 있다. 특히, 차선의 품질 규격이 KS M 6080 제품에 만족한다 하더라도 빗물의 수막(水膜)에 의한 유리알의 굴절율 차로 재귀반사기능을 하는 차선 도료용 유리알의 기능을 발휘하지 못하여 운전자의 시인성은 열악함을 알 수 있다. 따라서, 국외에서 많이 사용되고 있는 마모성이 우수한 수용성 차선도료, 고성능 융착식 도료, 상온경화형 도료를 도입하여 성능을 비교 검토하였다. 본 연구에서는 차선재료의 내구성 향상을 위해 EN 1436규격에 의한 내마모성 시험을 수용성, 융착식, 상온경화형 도료에 실시하여, 재귀반사도 성능이 우수한 차선재료의 적용 가능성을 확인하였다.

차선의 주요성능인 차선반사도는 도로의 기하구조 특성, 차선재료, 교통량, 일기, 환경요인등 다양한 요소에 의해 영향을 받게 된다. 그 결과 차선은 영향을 받은 정도에 따라 각기 다른 반사성능을 나타내게 된다. 본 논문은 공용중인 고속도로에서 차선의 반사성능 감소가 심할 것으로 예상되는 특정 기하구조 및 시설물 구간의 차선반사도 증감의 특성을 확인하여 밝히는 데 그 목적이 있다. 이를 통해 현행 최소차선반사도 기준과 비교하여 차선 반사도의 기하구조 또는 시설물 구간에 따른 차별적 관리가 필요하다는 주장을 제시하고자 한다. 데이타 분석을 위해 중부고속도로 하남JCT-남이JCT구간에서 황색실선. 백색점선의 차선반사도를 측정하였다. 이 측정치를 도로시설물 특이사항별로 구분하고, 각 구간에 대해 진입 전, 해당 구간, 통과 후로 구분하여 각각의 차선반사도를 비교 분석하였다. 분석결과 곡선구간, 오르막구간, IC램프구간, 터널구간에서 차선반사도가 상대적으로 낮게 측정되었다. 이로써 차선반사도의 기하구조 및 시설물 구간에 따른 차별적 적용 및 관리의 필요성을 제시하였다.