• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.13 no.2
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• pp.133-133
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• 1999

Average illuminance and luminance can be calculated by graphical methods to a certain extent but to calculate for a wide place a suitable software is needed. Softwares suitable for this purpose have been already developed in foreign nations, but the appropriate softwares for domestic use have not been developed. Therefore a program is developed which is executable in Hangul Windows. The softwares LAPRoad, is developed to calculate luminance and illuminance distribution of road surface, as well as average luminance and illuminance, overall uniformity, longitudinal uniformity, threshold increment veilling luminance and glare. And an apparatus that measures road surface reflection properties is developed. Because the road surface reflection properties is very important in luminance calculation, then concrete road surface reflection properties were measured.

• Journal of Environmental Science International
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• v.31 no.4
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• pp.329-339
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• 2022

Better understanding the mechanism of black ice occurrence on the road in winter is necessary to reduce the socio-economic damage it causes. In this study, intensive observations of road weather elements and surface information under the influence of synoptic high-pressure patterns (22^nd December, 2020 and 29^th January, and 25^th February, 2021) were carried out using a mobile observation vehicle. We found that temperature and road surface temperature change is significantly influenced by observation time, altitude and structure of the road, surrounding terrain, and traffic volume, especially in tunnels and bridges. In addition, even if the spatial distribution of temperature and road surface temperature for the entire observation route is similar, there is a difference between air and road surface temperatures due to the influence of current weather conditions. The observed road temperature, air temperature and air pressure in Nongong Bridge were significantly different to other fixed road weather observation points.

• Journal of the Korean Society of Safety
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• v.27 no.5
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• pp.211-218
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• 2012

Two experiment are planed to identify driver's safe driving behaviour by curve radius, road surface condition in curve section. At four-lane and two-lane road, conducted experiments are check on driver's feeling of safety that 30 subjects do not feel discomfort. And using the data from these experiments, this study compare physical speed (not slipping, fall our of the road) with safety driving speed(drivers felt a comfortable and safe speed) each curve radius and fiver road surface condition(drying, wet, rain, snow and ice). As a result, safe driving behaviour factors that are derived to curve radius of 100m units, five road surface conditions enable to represent quantitative analysis of driver's discomfort. This study will develop road design method and evaluation reflected ergonomic aspects.

• Wind and Structures
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• v.6 no.5
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• pp.325-346
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• 2003

High-sided road vehicles are susceptible to a sharp-edged crosswind gust, which may cause vehicle accidents such as overturning, excessive sideslip, or exaggerated rotation. This paper thus investigates the dynamic behaviour and possible accidents of high-sided road vehicles entering a sharp-edged crosswind gust with road surface roughness and vehicle suspension included. The high-sided road vehicle is modelled as a combination of several rigid bodies connected by a series of springs and dampers in both vertical and lateral directions. The random roughness of road surface is generated from power spectral density functions for various road conditions. The empirical formulae derived from wind tunnel test results are employed to determine aerodynamic forces and moments acting on the vehicle. After the governing equations of motion are established, an extensive computation work is performed to examine the effects of road surface roughness and vehicle suspension on the dynamic behaviour and vehicle accidents. It is demonstrated that for the high-sided road vehicle and wind forces specified in the computation, the accident vehicle speed of the road vehicle running on the road of average condition is relatively smaller than that running on the road of very good condition for a given crosswind gust. The vehicle suspension system should be taken into consideration, and the accident vehicle speed becomes smaller if the vehicle suspension system has softer springs and lighter dampers.

• Journal of the Korean Institute of Landscape Architecture
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• v.39 no.3
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• pp.107-116
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• 2011

One of the major factors which increase urban temperature is roads. This paper is aimed to investigate the effect of urban roadside vegetation on the road surface temperature. For this, surface temperature was measured at 18 spots using the thermal imaging camera in terms of road components including use of roadside land use, roadway, sidewalk, roadside vegetation and vegetation median barrier. The size of the roadside vegetation and related urban road characteristics were also measured. In terms of the effect of roadside vegetation on a decrease in road surface temperature, the roadside land use as a green area or open space was the highest, followed by the size of vegetation median barrier and the size of roadside vegetation. Besides road surroundings, an increase in the green zone such as roadside vegetation and median strip vegetation has a significant impact on lowering road surface temperature. Therefore, a good solution for reducing urban heat island effects would be to increase the area of roadside vegetation and green areas along roads.

• International Journal of Highway Engineering
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• v.19 no.6
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• pp.165-173
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• 2017

PURPOSES : The current practice in car headlight visibility performance evaluation is based on the luminous intensity and illuminance of headlight. Such practice can be inappropriate from a visibility point of view where visibility indicates abilities to perceive an object ahead on the road. This study aimed at evaluating the appropriateness of current headlight evaluation method. METHODS : This study measured the luminance of object and road surface at unlit roadways. The variables were measured by vehicle type and by headlight lamp type. Based on the measurements, the distance where drivers can perceive an object ahead was calculated and then compared against such distance obtained by conventional visibility performance evaluation. RESULTS : The evaluation method based on illuminance of headlight is not appropriate when viewed from the visibility concept that is based on object-perceivable distance. Further, the results indicated a shorter object-perceiving distance even when road surface luminance is higher, thereby suggesting that illuminance of headlight and luminance of road surface are not the representative indices of nighttime visibility. CONCLUSIONS : Considering that this study utilized limited vehicle types and that road surface (background) luminance can vary depending on the characteristics of the given road surface, it would likely go too far to argue that this study's visibility performance evaluation results can get generalized to other conditions. Regardless, there is little doubt that the current performance evaluation criterion which is based on illuminance, is unreasonable. There should be future endeavors on the current subject which will need to explore study conditions further, under which more experiments should be conducted and effective methodologies developed for evaluating automotive headlight visibility performance. Needs are recognized particularly in the development of headlight visibility performance evaluation methodology which will take into account road surface (background) luminance and luminance contrast from various perspectives as the former indicates the driver's perception of the front road alignment and the latter being indicative of object perception performance.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.3
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• pp.1098-1104
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• 2011

This paper presents the development of the surface profile sensing system (SPSS) and its application to analysis of road surface. The SPSS which can robustly reconstruct the road input profiles from the intermixed data with the vehicle's dynamic motion, is implemented using the multi-sensor system with the optimally shaped transfer function. The performance of this system is evaluated by a series of experimental works in the devised simulator. And a real car test equipped with the proposed system is performed in the proving ground over both deterministic and random road surfaces. Finally, a feasibility of the system is investigated considering the road model.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.17 no.6
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• pp.121-132
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• 2018

Weather is an important factor affecting roadway transportation in many aspects such as traffic flow, driver 's driving patterns, and crashes. This study focuses on the relationship between weather and road surface condition and develops a model to estimate the road surface condition using machine learning. A road surface sensor was attached to the probe vehicle to collect road surface condition classified into three categories as 'dry', 'moist' and 'wet'. Road geometry information (curvature, gradient), traffic information (link speed), weather information (rainfall, humidity, temperature, wind speed) are utilized as variables to estimate the road surface condition. A variety of machine learning algorithms examined for predicting the road surface condition, and a two - stage classification model based on 'Random forest' which has the highest accuracy was constructed. 14 days of data were used to train the model and 2 days of data were used to test the accuracy of the model. As a result, a road surface state prediction model with 81.74% accuracy was constructed. The result of this study shows the possibility of estimating the road surface condition using the existing weather and traffic information without installing new equipment or sensors.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.20 no.6
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• pp.101-107
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• 2020

Road surface measurement is an essential process for quantifying the degree and displacement of roughness in road surface management. For safer road surface management and quick maintenance, it is important to accurately measure the road surface while mounted on a vehicle. In this paper, we propose a sophisticated road surface measurement system that can be measured on a moving vehicle. The proposed road surface measurement system supports more accurate measurement of the road surface by using a high-performance line laser sensor. It is also possible to measure the transverse and longitudinal profile by matching the position information acquired from the RTK, and the velocity adaptive update algorithm allows a manager to monitor in a real-time manner. In order to evaluate the proposed system, the Gocator laser sensor, MRP module, and NVIDIA Xavier processor were mounted on a test mobile and tested on the road surface. Our evaluation results demonstrate that our system measures accurate profile base on the MSE. Our proposed system can be used not only for evaluating the condition of roads but also for evaluating the impact of adjacent excavation.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.44 no.2
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• pp.237-244
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• 2024

Pavement management systems (PMS) provide procedures to quantify road serviceability based on pavement conditions such as cracks and plastic deformation and suggest proper maintenance methods. The deterioration of the road pavement is relevant to the time although the quantifications on road serviceability in PMS present road surface conditions at the evaluation. More systematic evaluation on road serviceability may need time-dependent factors of road environments and that can improve PMS. Rainfall, temperature and vehicle loads can be environmental factors for road serviceability evaluation. As no data are avablie that can link between road conditions and environmental road factors, we conducted experiments to suggest economical devices and methods to obtain relevant data. We used temperature sensors and accelerometers with Arduino to measure road surface temperature and dynamic loads and provide data to improve pavement serviceability evaluation.