• The Journal of the Korea Contents Association
• /
• v.15 no.8
• /
• pp.69-76
• /
• 2015

With Various signs are installed at roadside to display the message which rather confuse the drivers. The technologies using advanced lighting system and LED have improved the visibility at nighttime but the problems with plural signs have yet to be resolved. In order to solve this problem, LED and the prismatic variable message sign have been applied. But, they have been provided limited information by the display limit. This research conducted to study patent and technical trend of the existing variable message signs to understand the present technology. And, we suggested next generation display to improve providing information. Therefore, we conducted to compare the LED and the OLED by technical and economical literature review. Also, this research conducted test of luminance contrast about the LED and the OLED display in order to understand the possibility of replacing road signs.

• Journal of Sensor Science and Technology
• /
• v.28 no.3
• /
• pp.157-163
• /
• 2019

The LiDAR sensor, which is widely regarded as one of the most important sensors, has recently undergone active commercialization owing to the significant growth in the production of ADAS and autonomous vehicle components. The LiDAR sensor technology involves radiating a laser beam at a particular angle and acquiring a three-dimensional image by measuring the lapsed time of the laser beam that has returned after being reflected. The LiDAR sensor has been incorporated and utilized in various devices such as drones and robots. This study focuses on object detection and recognition by employing sensor fusion. Object detection and recognition can be executed as a single function by incorporating sensors capable of recognition, such as image sensors, optical sensors, and propagation sensors. However, a single sensor has limitations with respect to object detection and recognition, and such limitations can be overcome by employing multiple sensors. In this paper, the performance of an eight-channel scanning LiDAR was evaluated and an object detection algorithm based on it was implemented. Furthermore, object detection characteristics during daytime and nighttime in a real road environment were verified. Obtained experimental results corroborate that an excellent detection performance of 92.87% can be achieved.

• Journal of Korean Society of Transportation
• /
• v.35 no.4
• /
• pp.261-277
• /
• 2017

This study defines influencing sections as the part of the road section where passing vehicles are traveling with the lower speed compared to speed limit due to speed humps. The influencing section was divided into 3 parts; influencing section before the speed hump, interval section, and influencing section after the speed hump. This analysis focused on the changes of each part depending on installation types, vehicle types, and daytime or nighttime. For the interval section, especially, the ratio of distance traveled with lower speed than speed limit to interval section is defined as effective influencing section ratio to be analyzed. Vehicle speed profiles were collected with a speed gun to extract influencing section lengths. The survival analysis was applied and estimated survival functions are compared with each other by several statistical tests. As a consequence, the average length of influencing section on the 50m sequential speed humps was 75.3% longer during the deceleration than that of isolated speed hump, and 18.9% during the acceleration. The effective influencing section ratio for the 30m and 50m sequential speed humps had a small difference of 81.0% and 76.0% while the absolute values of the section that passing speed were less than the speed limit were longer on 50m sequential speed humps, each being 24.3m and 38.0m. Using the log rank test, it was evident that sequential speed humps were more effective to increase the length of influencing sections compared to the isolated speed hump. Vehicle type was the strong factor for influencing section length on the isolated speed hump, but daytime or nighttime was not the effective one. This research result can be used for improving the efficiency selecting the installation point of speed humps for road safety and estimating the standard of the distance between sequential speed humps.

• Journal of Broadcast Engineering
• /
• v.22 no.3
• /
• pp.282-294
• /
• 2017

In this paper, we propose a novel intelligent headlight control (IHC) system which is durable to various road lights and camera movement caused by vehicle driving. For detecting candidate light blobs, the region of interest (ROI) is decided as front ROI (FROI) and back ROI (BROI) by considering the camera geometry based on perspective range estimation model. Then, light blobs such as headlights, taillights of vehicles, reflection light as well as the surrounding road lighting are segmented using two different adaptive thresholding. From the number of segmented blobs, taillights are first detected using the redness checking and random forest classifier based on Haar-like feature. For the headlight and taillight classification, we use the random forest instead of popular support vector machine or convolutional neural networks for supporting fast learning and testing in real-life applications. Pairing is performed by using the predefined geometric rules, such as vertical coordinate similarity and association check between blobs. The proposed algorithm was successfully applied to various driving sequences in night-time, and the results show that the performance of the proposed algorithms is better than that of recent related works.

• Journal of the Korean Regional Science Association
• /
• v.38 no.3
• /
• pp.3-17
• /
• 2022

The automobile-centered lifestyle has provided many advantages to urban residents, but it is also causing various problems. Among them, illegal parking is one of the representative urban problems that negatively affect them. The purpose of this study is to derive the urban environmental factors affecting illegal parking and provide policy implications by using data related to illegal parking among civil complaints about smart inconvenience reports in Seoul in 2019. It was judged that the influencing factors would differ depending on the time of the complaint, and the analysis was conducted by dividing the time of the complaint into a whole day, daytime, and nighttime. As a result of the analysis of this study, it was found that land-use variables and the number of POI facilities were closely related to illegal parking complaints. Also, the subway station area and road width were found to be closely related to illegal parking complaints. On the other hand, parking facilities did not show significant results with illegal parking complaints. This study showed that the use of civic complaint data could be used as important data to identify urban problems that city residents actually experience and to come up with policy implications.