• International Journal of Highway Engineering
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• v.17 no.4
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• pp.63-68
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• 2015

PURPOSES : A study on the efforts to minimize the road traffic noise has been underway. An attempt has been made to measure the noise level using a noise map; however, the attempt is limited to certain areas only. In general, a noise barrier is employed to prevent road traffic noise; however, unplanned noise barriers developed without considering the surrounding environment, including excessively high walls, cause problems such as infringement on prospect right. Noise ceiling at daytime in Korea is 68 dB(A), which is relatively higher than in other countries. METHODS: The noise barrier used mainly for road noise reduction was analyzed to estimate the optimal height. Related variables such as road width, the height of the upper part, distance to the building, and angle (for instance, $30^{\circ}$). RESULTS : A formula to calculate the optical height of the noise barrier, considering the road environment (i.e., parameters such as road width and distance to building), was developed in this study in an attempt to mitigate the noise generated from the road. CONCLUSIONS : The formula to calculate the noise barrier is expected to lead to cost saving, accurate installation of barriers, and protection of the right of prospect.

• Journal of Forest and Environmental Science
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• v.20 no.1
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• pp.93-109
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• 2004

To provide the basic informations related to forest road construction of mountainous terrain, we analyzed changes of the road structure factors such as banking and cutting slope gradients, slope length, road width by the environmental factors such as locations, slope gradients, soil types, road position on physically stabilized forest roads constructed in Gangwon-do. All factors related to the road structures by locations were significant except for banking slope length. Road width, longitudinal gradients, banking and cutting slope length by slope gradients were not significantly different and banking slope gradients in the range less than $30^{\circ}$, from $30^{\circ}$ to $35^{\circ}$ and more than $40^{\circ}$ and cutting slope gradients were significantly different for all areas. Road width, longitudinal gradients, banking slope length by soil types were not significantly different and others were significantly different. All factors related to the road structures by road position were significant except for cutting slope gradients.

• Journal of Power System Engineering
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• v.6 no.2
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• pp.54-59
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• 2002

The principle of the FDM(fused deposition modeling) process is based on the layer by layer manufacturing technology, like other RP(rapid prototyping) process. In the FDM process, each layer may have different shape. Therefore, the built model may have stairs shape on its surface. This stairs shape is one of the serious problems in the FDM process. Thus in this study, cube models and spherical models were fabricated by FDM process to investigate the influence of injection amount on surface roughness. Models with various road width were also built to investigate the influence of road width on surface roughness. Surface roughness of the models was measured and analyzed. The result obtained in this study are expected to help selecting the part build orientation for optimum surface roughness.

• Journal of the Korea Institute of Military Science and Technology
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• v.14 no.6
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• pp.993-1001
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• 2011

Unmanned ground vehicle for facility protection mostly uses model of territory for autonomous navigation. However, modeling of territory using several sensors is highly time consuming and sometimes inefficient for road application. Therefore, an estimation of drivable path based on features of road is required for high speed autonomous navigation on road. In this paper, an estimation method of drivable path using camera and 2D laser rangefinder is proposed. First, a vanishing point is estimated based on image data from CCD camera. Second, a road width is estimated based on range data from 2D laser rangefinder. Finally, the drivable path is estimated by fusing the vanishing point and the road width. The proposed method is tested on both well-structured road and unpaved road like cross-country situation.

• International Journal of Highway Engineering
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• v.20 no.2
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• pp.87-96
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• 2018

PURPOSES : The purpose of this study is to compare the consistency of widths by analyzing the current situation of the sidewalk in Korea and Japan Neighborhoods Area. METHODS : Literature on the sidewalk width of the Neighborhood Area is reviewed to compare the consistency of width. Through on-site surveys, We identify the current status of sidewalk in Korea and Japan. This compares the sidewalk width consistency in the Neighborhood Area. RESULTS : The width of whole sidewalks in Japan is ranged 330~445cm, which is lAvger than The width of whole sidewalks in Korea, ranged 237~420cm. Frontage Zone width is ranged 60~65cm in Japan, similar to 60cm in Korea. However, in Korea, there is a lAvge difference between Frontage Zone width and walking width average, and the standard deviation of width is lAvger than Japan. The Pedestrian Zone width is ranged 172~325cm in Japan, which is lAvger than ranged 0~295cm in Korea. The width of the Furniture Zone is ranged 135 ~ 331cm in Japan and lAvger than ranged 90~225cm in Korea. In Korea, the difference between the Furniture Zone width and the walking average width is small, and the standard deviation of width is smaller than that of Japan. CONCLUSIONS : In conclusion, the standard deviation of the frontage zone and the pedestrian zone width, which are included in the valid sidewalk width, The Korea is lAvger than in Japan. valid sidewalk width of Korea sidewalk is inconsistent. valid sidewalk width for wheelchair users does not meet the width of more than 2 meters.

• The Journal of Engineering Geology
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• v.24 no.3
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• pp.333-341
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• 2014

The construction of roads, tunnels, and bridges results in changes to the local terrain that may influence the ground safety factor, which represents the stability of geotechnical structures. In this study, we assessed construction sites that had collapsed as a result of terrain change, and then simulated variation in the ground safety factor with respect to terrain change caused by road construction. We assumed steep slopes to simulate changes in terrain in a mountainous area and assumed that earthworks took place for road construction by cutting a platform into the slope and altering the slope angle of the terrain both above and below the road. We calculated values of the ground safety factor through a stability analysis of the slope both above and below the road, and examined the variation in the safety factor of the above- and below-road slopes with respect to changes in road width. We found that if the slope angle was the same above and below the road, then the change in the ground safety factor during/after road construction occurred in the slope below the road, and if the slope angle above the road differed from that below, then the change occurred in both the above- and below-road slopes. Furthermore, the ground safety factor was essentially constant for road widths exceeding 2-6 m, depending on both above- and below-road slope angle. The findings of this study can be used to guide the management of construction sites and to assess changes in ground stability during road construction work, particularly in the early stages of earthworks, when the road width is narrow.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.2 no.1
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• pp.45-50
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• 2003

In any rapid prototyping process, the layer by layer building process introduces an area error between the staircase and the surface line specified by the computer-aided design model. This affects the dimensional accuracy as well as the surface finish for different Road Widths. This paper describes a methodology for computing the area error for any Road Width by the fused deposition modelling system. This technique can be applied to determine the best Road Width of the part, based on the minimum area error. This technique is verified by comparing the results with the experimental measurements of the area error with Road Widths.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.51-56
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• 2011

The train travels on the track and, thus, the rear wheels precisely follow the paths of the front wheels. On the contrary, in the vehicles running on the road like automobiles, buses and trucks, the front wheels try to drag the rear ones toward them and across the inside of the curve. Off-tracking is defined as the radial offset between the path of the centerline of the front axle and the path of the centerline of the following axle. In the case of the bimodal tram with AWS(all wheel steering), the off-tracking decrease but the rear swing-out values increase because of the rear steering at the reverse phase angle. Thus, in order to determine the swept path width, maximum road width at the minimum turning radius, off-tracking and swing-out should be considered for the bimodal tram. In this paper, trajectory simulations were carried out for the various condition such as front steering, front and rear steering and suppression of swing-out to optimize the swept path width.

• International Journal of Highway Engineering
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• v.19 no.2
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• pp.167-174
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• 2017

PURPOSES: This study aims to analyze the impact of the implementation of a school zone traffic safety improvement project on the number of accidents involving children in these zones. METHODS : To analyze the correlation between school zone traffic safety features of roads in the zone and the number of accidents involving children, we developed an occurrence probability model of traffic accidents involving children by using a binary logistic regression model with SPSS 23.0 software. Two separate models were developed for two zones: interior block and arterial road. RESULTS :The model depicted that in the case of the interior block, shorter sidewalk width, speed bump, and an elevated crosswalk were key factors affecting the occurrence of accidents involving children. In the case of arterial roads exceeding a width of 12 m, the speed limit, roadside barriers, and red paving of road surfaces were found to be the key factors. CONCLUSIONS:The results of this study can serve as the elementary research data to help improve the effectiveness of school zone traffic safety improvement projects and school zone road repair projects in future.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.41 no.4
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• pp.377-386
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• 2021

In dense cities, which are covered by many impermeable areas, rainwater flows quickly along the roads and collects in certain areas. The surface runoff that fails to get intercepted by the roadside rain gutters results in a wider flow of water along the sides, which in turn increases the amount of water on the road and causes traffic congestion as well as accidents due to slippage. Based on these issues, this study was carried out in order to propose an intercepted flow calculation formula. To this end, the maximum longitudinal slopes of arterial roads and expressways were reflected to depict a road condition of 2~10 %, while a general traverse slope of 2 % was selected for the traverse slope on the side. As for the road lane condition, two, three, and four lanes were chosen for the area from the centerline to the sidewalk. As for the experimental flow rate, the rainwater runoffs at the actual design frequency of 5, 10, 20, and 30 years for road conditions were converted into experimental flow rates, and as a result, flow rates ranging from 1.36 l/s to 3.96 l/s were divided into ten flow rates for a hydraulic experiment. Also, an equation taking into consideration the inflow velocity and flow width along the roadsides was proposed. The results of the experiment showed an increase in flow width and a decrease in interception rate. Also, the inflow velocity at a traverse slope of 2 % was measured, while increasing the longitudinal slope. Accordingly, an equation for calculating the flow intercepted by rain gutters at a flow width reflecting the longitudinal slope of the road and rainwater runoff, according to the design frequency, was derived by performing a regression analysis using IBM SPSS Statistics 24. It is deemed that the equation derived in this study will be useful in designing rain gutters for roads.