• Journal of Korean Society of Transportation
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• v.29 no.2
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• pp.123-131
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• 2011

This study proposes a model for road surface temperature prediction on basis of the heat-energy balance equation between atmosphere and road surface. The overall model is consisted of two types of modules: 1) Canopy 1 is used to describe heat transfer between soil surface and atmosphere; and 2) Canopy 2 can reflect the characteristics of pavement type. Input data used in the model run is obtained from the Korea Meteorological For model validation, the observed and predicted surface temperature data are compared using data collected on MoonEui Bridge along CheongWon-Sangju Expressway, and the comparison is made on winter and other seasons separately. Analysis results show that average difference between two temperatures lies within ${\pm}2^{\circ}C$ which is considered as appropriate from a micrometeorology point of view. The model proposed in this paper can be adopted as a useful tool in practical applications for winter maintenance. This study being a fundamental research is anticipated to be a starting point for further development of robust surface road temperature prediction algorithms.

• International Journal of Internet, Broadcasting and Communication
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• v.15 no.1
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• pp.85-96
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• 2023

The number of traffic accidents caused by wet or icy road surface conditions is on the rise every year. Car crashes in such bad road conditions can increase fatalities and serious injuries. Historical data (from the year 2016 to the year 2020) on weather-related traffic accidents show that the fatality rates are fairly high in Korea. This requires accurate prediction and identification of hazardous road conditions. In this study, a forecasting model is developed to predict the chances of traffic accidents that can occur on roads affected by weather and road surface conditions. Multiple deep learning algorithms taking into account AlexNet and 2D-CNN are employed. Data on orthophoto images, automatic weather systems, automated synoptic observing systems, and road surfaces are used for training and testing purposes. The orthophotos images are pre-processed before using them as input data for the modeling process. The procedure involves image segmentation techniques as well as the Z-Curve index. Results indicate that there is an acceptable performance of prediction such as 65% for dry, 46% for moist, and 33% for wet road conditions. The overall accuracy of the model is 53%. The findings of the study may contribute to developing comprehensive measures for enhancing road safety.

• Transactions of the Korean Society of Automotive Engineers
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• v.2 no.1
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• pp.128-141
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• 1994

This roport explain the basic theory of desinging the accelerating durability test road and the role of each factors contributing to test road surface profile. Also this road is designed by considering the charactors of vehicle suspension system and condition of driving. In test road, the factors affecting to the vehicle Structural durability are correlation among surface shape of road profile, frequency of vehicle suspension system, distribution of axletwist angle and vibration profile height Road PSD magnitude and frequency delay is used to control these factors relation.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.14 no.2
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• pp.30-38
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• 2015

In this study, to improve effectiveness of road management services and the safety of the road in winter, road surface temperature prediction model was developed. We have utilized the existing input data of meteorological data and additional traffic data. This Road surface temperature prediction model was utilizing a Heat-Balance Method additionally considering amount of traffic that produce heat radiation by vehicle-tire friction. This improved model was compared to the based model to check into influence of traffic affecting the road surface temperature. There were verified by comparing the real observed road surface temperature of the third Gyeong-In highway and road surface temperature from the two models. As a result, the error of real observed and the predicted value (RMSE) was found to average $1.97^{\circ}C$. Observed road surface temperature was dramatically affected by the sunlight from 6 a.m. to 2 p.m. and degree of influence decreases after that. The predictive value of the model is lower than the observed value in the afternoon, and higher at night. These results appear due to the shielding of solar radiation caused by the vehicle in the afternoon and at night, the vehicle appeared to cause thermal heat supply.

• Journal of the Korean Association of Geographic Information Studies
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• v.23 no.4
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• pp.156-172
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• 2020

The purpose of this study was to predict road surface temperature using high-resolution solar radiation data. The road surface temperature prediction model (RSTPM) was applied to predict road surface temperature; this model was developed based on the heat-balance method. In addition, using SOLWEIG (SOlar and LongWave Environmental Irradiance Geometry-model), the shadow patterns caused by the terrain effects were analyzed, and high-resolution solar radiation data with 10 m spatial resolution were calculated. To increase the accuracy of the shadow patterns and solar radiation, the day that was modeled had minimal effects from fog, clouds, and precipitation. As a result, shadow areas lasted for a long time at the entrance and exit of a tunnel, and in a high-altitude area. Furthermore, solar radiation clearly decreased in areas affected by shadows, which was reflected in the predicted road surface temperatures. It was confirmed that the road surface temperature should be high at topographically open points and relatively low at higher altitude points. The results of this study could be used to forecast the freezing of sections of road surfaces in winter, and to inform decision making by road managers and drivers.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.5
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• pp.82-88
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• 2018

This study investigated the structure of an 8-pole 8-slot linear generator, which acts as an electromagnetic damper by combining the structure of an electromagnetic suspension device capable of generating electrical energy through energy harvesting by absorbing the vibration energy from the road surface while driving. To compare the energy harvesting effect of the electromagnetic suspension according to the actual road surface, a driving road test was simulated for two actual road conditions, an asphalt road surface and unpacked road surface condition, using a civilian combined vehicle model in conjunction with a vehicle simulation program, Carsim and Simulink. As a result, the relative displacements of the suspensions on the asphalt road surface and the unpaved road were 8 mm and 13 mm, respectively. By applying the suspension displacement value derived by modeling the linear generator coupled to the electromagnetic suspension, the simulation was then performed for an analysis time of 0.3s by applying the same analytical conditions using the commercial electromagnetic analysis program, ANSYS MAXWELL, The average power generation on the unpacked roads and asphalt roads was 198.6W and 98.7W respectively, which was 103.7% higher for unpackaged roads. Finally, to compare the sensitivity of the road surface frequency and the suspension input displacement to the power generation output, the sensitivity of the two variables was 1.725 and 1.283, respectively, and the road surface frequency had a 34.5% higher effect on the average power generation.

• International Journal of Highway Engineering
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• v.6 no.4 s.22
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• pp.35-43
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• 2004

Skid resistance is an important factor that control braking distance and secure safety by preventing slipperiness between tire and pavement surface. Decrease of skid resistance at wet condition may cause fatal traffic accidents. Dirt materials such as sand and do-icings on the road surface also can be a factor for decrease skid resistance. This study makes an investigation into influence of skid resistance between varied cement concrete pavements about surface texturing method(transverse tining, longitudinal tining, exposed aggregate surface texturing method) and wearing condition of pavement surface texture(new constructed pavement's surface, wore pavement's surface) using accelerate concrete pavement wearing tester when remains of dirt material are obtained between tire and road surface on PCC pavement. As dirt material on road surface of concrete pavement, sand, calcium chloride and old oil were used with different amount of each cases.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.18 no.3
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• pp.13-22
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• 2015

Unpaved forest roads are common accessways in mountain areas being used for forestry purposes. The presence of forest roads produces large volumes of surface runoff and sediment yield due to changes in soil properties and hillslope profile. Rainfall simulation experiments were conducted to estimate the impacts of above-ground vegetation and antecedent soil water condition on hydrology and sediment processes. A total of 9 small plots($1m{\times}0.5m$) were installed to represent different road surface conditions: no-vegetation(3 plots), vegetated surface(3 plots), and cleared vegetation surface(3 plots). Experiments were carried out on dry, wet, and very wet soil moisture conditions for each plot. Above ground parts of vegetation on road surface influenced significantly on surface runoff. Runoff from no-vegetation roads(39.24L) was greater than that from vegetated(25.05L), while cleared-vegetation condition is similar to no-vegetation roads(39.72L). Runoff rate responded in a similar way to runoff volume. Soil erosion was also controlled by land cover, but the magnitude is little than that of surface runoff. Even though slight differences among antecedent soil moisture conditions were found on both runoff and soil erosion, runoff rate and soil losses were increased in very wet condition, followed by wet condition. The experiments suggest that vegetation cover on forest road surface seems most effective way to reduce surface runoff and soil erosion during storm periods.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.8 no.2
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• pp.40-45
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• 2009

This study is analyzed by stress contour of automotive tire at contact on road surface. Maximum equivalent stress as 61200Pa is shown on the lower mid part in case of tire contacted on road surface. As the air pressure of tire increases, maximum total deformation as 5mm is shown on the side part of tire. It can be shown that the side part of tire is unstabilized. There is no load effect on tire at its upper and lower directions. When the moment applied on the side of tire is increased 1.4 times as its value, the value of maximum principal stress is increased 1.4 times. The stress at the tire is in proportion to the moment applied on the its side. The tire tends to incline toward its side by this moment.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.125-125
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• 2000

An Empirical approach to determine a road-surface condition is presented The road-surface condition thus provided includes the detection of not only friction coefficient, but also abrupt surface-profile changes such as pitfalls and bumpers The former plays a key role in establishing the appropriate control strategy, while the latter allows to minimize unnecessary brake intervention induced by the aforementioned jut. In this paper, we use an empirically chosen variable, namely. the time-rate of change of vehicle speed estimated from the point where ABS engaged to the point where measurement taken Experimental results shoe that the proposed method is effective to infer various control variables critical for the control of ABS.