• Journal of Advanced Navigation Technology
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• v.16 no.6
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• pp.944-951
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• 2012

The conventional indexes for describing the GNSS positioning performance such as satellite visibility, dilution of precision (DOP) and signal to noise ratio is very useful in open sky, however, they are not useful in the land road environment. In this paper new index is suggested for describing the GNSS positioning performance for the road environment. The new index is called Sky View based DOP (SVDOP). SVDOP is derived referring the Sky-View-Factor (SVF). The usefulness is analyzed by comparing the SVDOP and SVF in land road environment after the singularity points are selected and SVDOP is calculated.

• KIPS Transactions on Software and Data Engineering
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• v.4 no.11
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• pp.521-528
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• 2015

Road-view object classification methods are mostly influenced by weather and illumination conditions, thus the most of the research activities are based on dataset in clean weathers. In this paper, we present a road-view object classification method based on color segmentation that works for all kinds of weathers. The proposed method first classifies the weather and illumination conditions and then applies the weather-specified color models to find the road traffic signs. Using 5 different features of the road-view images, we classify the weather and light conditions as sunny, cloudy, rainy, night, and backlight. Based on the classified weather and illuminations, our model selects the weather-specific color ranges to generate Gaussian Mixture Model for each colors, Green, Yellow, and Blue. The proposed method successfully detects the traffic signs regardless of the weather and illumination conditions.

• Journal of Digital Convergence
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• v.15 no.1
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• pp.239-245
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• 2017

For privacy protection, we propose a vehicle license plate region detection method in road view image served from portal site. Because vehicle license plate regions in road view images have different feature depending on distance, long distance vehicle license plate regions are not detected by feature of low resolution. Therefore, we suggest a method to detect short distance vehicle license plate regions by edge feature and long distance vehicle license plate regions using MSER feature. And then, we select candidate region of vehicle license plate region from detected region of each method, because the number of the vehicle license plate has a structural feature, we used it to detect the final vehicle license plate region. As the experiment result, we got a recall rate of 93%, precision rate of 75%, and F-Score rate of 80% in various road view images.

• Atmosphere
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• v.31 no.5
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• pp.525-537
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• 2021

Black ices on road surfaces in winter tend to cause severe and terrible accidents. It is very difficult to detect black ice events in advance due to their localities as well as sensitivities to surface and upper meteorological variables. This study develops a methodology to detect the road sections vulnerable to black ice with the use of road surface temperature data obtained from a mobile road weather observation vehicle. The 7 experiments were conducted on the route from Nam-Wonju IC to Nam-Andong IC (132.5 km) on the Jungang Expressway during the period from December 2020 to February 2021. Firstly, temporal road surface temperature data were converted to the spatial data with a 50 m resolution. Then, the spatial road surface temperature was normalized with zero mean and one standard deviation using a simple normalization, a linear de-trend and normalization, and a low-pass filter and normalization. The resulting road thermal map was calculated in terms of road surface temperature differences. A road ice index was suggested using the normalized road temperatures and their horizontal differences. Road sections vulnerable to black ice were derived from road ice indices and verified with respect to road geometry and sky view, etc. It was found that black ice could occur not only over bridges, but also roads with a low sky view factor. These results are expected to be applicable to the alarm service for black ice to drivers.

• 제어로봇시스템학회:학술대회논문집
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• 1991.10a
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• pp.773-778
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• 1991

In this paper we describe a road following method for an autonomous vehicle. From a road image in gray level, a road boundary is detected using a gradient operator, and then the road boundary is converted to orthogonal view of the road showing the vehicle position and heading direction. In this research an efficient road boundary search technique is developed to support real time vehicle control. Also, an obstacle detection method, using images taken from two different positions, has been developed.

• International Journal of Highway Engineering
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• v.7 no.4 s.26
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• pp.163-171
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• 2005

Current roads were designed and constructed based on the design criteria and thus those were overly simplified drivers' needs. The road criteria do not suggest the desirable range of the design values but suggest the minimum requirements for the road design. Therefore, a completed road design based on the design criteria does not always guarantee the best design in terms of safety and it sometimes violates drivers' expectation. Therefore, the ROSSAV(ROad Safety Survey and Analysis Vehicle) is being developed by the KICT to evaluate road safety and increase driving safety. In this paper, the image capture system was described in detail. The image capture system is consisted of two front view cameras, two side down-looking cameras and a synchronization device. Two front view cameras were used to take a picture of road and road facilities at the driver's viewpoint. Also, two side down-looking cameras were used to capture road surface image to extract lane markings. A synchronization device were used to generate image capturing signal at the fixed distance spacing huck as every 10m. The front view images could be used to calculate and measure highway geometry such as shoulder width because every image is saved with it's locational information. And also the side down looking images could be used to extract median lane mark which representing road alignement efficiently.

• Journal of KIISE:Software and Applications
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• v.36 no.8
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• pp.653-663
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• 2009

In this paper, we propose a blind spots elimination system using three cameras. A wide-angle camera is attached on trunk for eliminating blind spots of a rear-view mirror and two cameras are attached on each side-view mirror for eliminating blind spots of vehicle's sides. In order to eliminate blind spots efficiently, we suggest a method to build a panoramic mosaic view with two side images and one wide-angle rear image. First, we obtain an undistorted image from a wide-angle camera of rear-view and calculate the focus-of-contraction (FOC) in undistorted images of rear-view while the car is moving straight forward. Second, we compute a homography among side-view images and an undistorted image of rear-view in flat road scenes. Next, we perform an image registration process after road and background region segmentation. Finally, we generate various views such as a cylinder panorama view, a top view and an information panoramic mosaic view.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2004.11a
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• pp.519-522
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• 2004

The purpose of this research is to design a road using digital photogrammatry method to generate DEM(digital elevation model) and digital ortho image based on GSIS which was applied to the road simulation. The example study area was the suburbs of Jeju city. To this study, 1/5,000 digital map and GSIS technique were used for optimum road design of the island based on Arc View software. Using this software we can Set an overlay map by combination of hill shade map, slope map, aspect map, and building buffer map. Based on this overlap map, we designed the best road line and along this line we performed three dimensional road simulation using Microstation CAD and Inroads road design programs. From the results, we found that the DEM and digital ortho image acquired from stereoairphoto using digital photogrammatry was satisfied for choosing the best roadline and the developed three dimensional road simulation technique using GSIS technique was very useful to estimate the reasonable road design before the real road construction works.

• The KIPS Transactions:PartB
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• v.18B no.5
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• pp.255-264
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• 2011

In this paper, we propose a forward vehicle detection algorithm using column detection and bird's-eye view mapping based on stereo vision. The algorithm can detect forward vehicles robustly in real complex traffic situations. The algorithm consists of the three steps, namely road feature-based column detection, bird's-eye view mapping-based obstacle segmentation, obstacle area remerging and vehicle verification. First, we extract a road feature using maximum frequent values in v-disparity map. And we perform a column detection using the road feature as a new criterion. The road feature is more appropriate criterion than the median value because it is not affected by a road traffic situation, for example the changing of obstacle size or the number of obstacles. But there are still multiple obstacles in the obstacle areas. Thus, we perform a bird's-eye view mapping-based obstacle segmentation to divide obstacle accurately. We can segment obstacle easily because a bird's-eye view mapping can represent the position of obstacle on planar plane using depth map and camera information. Additionally, we perform obstacle area remerging processing because a segmented obstacle area may be same obstacle. Finally, we verify the obstacles whether those are vehicles or not using a depth map and gray image. We conduct experiments to prove the vehicle detection performance by applying our algorithm to real complex traffic situations.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.325-328
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• 2008

After insufficient road facilities are expanded, it is more important to maintain performance of road facilities the time according to passing. When the road facilities are maintained optimally through proper maintenance, the total amount of investment can be minimized and national competitiveness is improved. Individual maintenance research of road facilities such as PMS or BMS was in progress until currently, but it is difficult to joint ownership and share information between systems, and it is impossible to use as the decision-making. Therefore, Asset Management System for road facilities is enforced to solve the inefficiency of existing systems, maintenance the road facilities systematically under the limited budget and get the maximum benefits against the cost from the view point of long-term. In this paper, the concept of Asset Management System explained, and research plan from KICT in order to introduce the Asset Management System of road facilities from 2008 hereafter for 5 years accounted.