• Journal of KIISE:Computer Systems and Theory
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• v.35 no.8
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• pp.385-393
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• 2008

The best coverage problem is finding a path whose worst distance to the sensor-set is the best among all paths. Instead, if the user stays close to its nearest two sensors, then the stability of the wireless connection may be guaranteed. So we consider the problem of finding a second best coverage path; given the sensor set U, a starting point s and a target point t, find a path whose worst distance to the second closest sensor is minimized. This paper presents an O(n logn) -time algorithm to find such a path. We also give experimental evidence showing that the connection to the sensor-set along a second best coverage path is more stable than that along the best coverage path.

• Proceedings of the Korean Information Science Society Conference
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• 2007.10b
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• pp.457-462
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• 2007

사용자가 가능한 센서 가까이에서 이동하는 문제를 최단거리유지문제라 하며, 무선 연결의 안정성을 높이기 위해서 두 개의 센서로부터 가까이에 위치하여 사용자가 움직이는 이동경로를 차선최단거리유지이동경로라고 한다. 이 논문에서는 주어진 센서들의 집합 U와 시작점 s, 끝점 t가 주어질 때, s에서 t까지 이르는 경로로서, 가장 가까운 두 개의 센서까지의 거리가 최소인 차선최단거리유지이동경로를 찾는 $O((c^2n+e)log(c^2n))$-시간 알고리즘을 제시한다. 여기서 c는 집합 U의 하나의 사이트가 갖는 최대 보로노이 선분의 개수이다.

• Annual Conference of KIPS
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• 2019.10a
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• pp.325-328
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• 2019

자율주행 자동차는 운전자가 개입하지 않고 차량에 부착된 다양한 센서를 통해 얻은 데이터를 기반으로 차량을 스스로 제어하며 설정한 목적지까지 주행한다. 본 논문에서는 단일 카메라와 영상을 사용한 차선 검출하고 추적하는 방법을 제안한다. 영상의 하단 부분만 분리하여 차선을 검출하기 위하여 외곽선 검출 과정을 거친 후 허프 변환을 통해 양 차선의 중심을 구한다. 이 값을 바탕으로 PID 제어로 차량의 차선을 유지한다. 모형 차량과 모형 트랙에서 차선 인식 후 차선을 추적하여 주행하는 동작을 시험하였다. PID 제어를 위헌 적정 각 항의 값을 구하였다. 시험 결과 차선 검출 알고리즘은 성공적으로 동작함을 확인할 수 있었다.

• Journal of the Korean Professional Engineers Association
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• v.28 no.4
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• pp.54-75
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• 1995

This synthesis has been prepared from a review of literature on Truck Escape Ramps technology and a survey of current practice by state department of transportation. Their locations have been determined usually from a combination of accident experience and en-gineering judgement, but new tools are emerging that can identify needs and sites without waiting for catastrophic accidents to happen. The Grade Severity Rating Systems holds promise in this regard. Design Procedures for truck excape ramps continue to evolve. Gravel arrester beds are clearly the preferred choice across the country Rounded aggregate, uniformly graded in the approximate size range of 13 to 18mm. Tech-nical publications typically have dassified TER types as paved gravity, sandpile, and ar-rester bed ramps. The design speed for vehicle entry into the ramp in critical to the deter-mination of ramp length. An escape ramp should be designed for a minimum entry speed of 130km/hr, a 145km/hr design being preferred. The ramps should be straight and their angle to the roadway align-ment should be as possible. The grade of truck escape ramps show the adjustment of ramp design to local topography, such as the tradeoff of ramp length against earthwork requirements. A width of 9 to 12m would more safety acommodate two or more outof con-trol vehicles. Reguarding comments on the most effective material, most respondents cited their own specification or referred to single graded, rounded pea gravel. The consensus essentially Is that single graded, well -rounded gravel is the most desirable material for use in arrester beds. The arrester beds should be constructed with a minimum aggregate depth of 30cm. Successful ramps have used depths between 30 and 90cm.

• Journal of Korean Society of Transportation
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• v.8 no.2
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• pp.109-118
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• 1990

본 고는 도로선형 설계에 확율 및 경제요소를 반영시키는 방법과 그에 따른 효과를 파악하는데 목적을 두고 있다. 접근방법은 도로사용자 비용과 도로시공 및 유지관리 비용 등을 포함하는 총비용을 예상비용함수로 나타내어 이 비용함수를 최소화함으로써 최적 도로선형 설계방법을 찾는 것이다. 이와 더불어 본 고는 이 개념에 의한 최적 설계방법을 등반차선(Climbing lane)의 설계에 적용하였다. 즉, 오르막길의 경사 및 거리에 따른 등반차선의 최적 위치를 찾기 위해 우선 오르막길에서의 승용차와 트럭의 속도분포를 찾아내고 예상예비함수를 등식화하여 그 최적해를 구함으로써 등반차선의 최적 위치를 구하였다. 현재 등반차선의 설계과정(AASHTO, 1984)은 트럭 주행능력에 따른 가정과 트럭과 승용차의 최대 속도 차이를 임의로 선택하여 등반차선의 최적 위치를 찾고 있다. 따라서 본 고에서는 기존 등반차선 설계방법과 새로운 설계방법을 상호 비교하면서 새로운 방법의 타당성과 그에 따른 설계이점들을 증명하였다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.8
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• pp.1553-1559
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• 2017

This paper proposes a lane departure detection algorithm using a single camera equipped in front of a vehicle. The proposed algorithm generates a partial top-view image for a small ROI (region of interest) designated on the top-view space form the image acquired by the camera, detects lanes on the small partial top-view image, and makes a decision on the lane departure by checking overlap between the pre-assigned virtual vehicle and the detected lanes. The proposed algorithm also includes the removal of lines occurred by road symbols (noises) disturbing the lane departure detection between lanes and the prediction of lost lanes using lane information of previous fames. In lane departure detection test using real road videos, the proposed algorithm makes the right decision of 99.0% in lane keeping conditions and 94.7% in lane departure conditions.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.22 no.3
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• pp.434-442
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• 2018

In this paper, we propose a road lane color recognition method from the image obtained from a driving vehicle. In autonomous vehicle techniques, lane information becomes more important as the level of autonomous driving such as lane departure warning and dynamic lane keeping assistance is increased. In particular the lane color recognition, especially the white and the yellow lanes, is necessary technique because it is directly related to traffic accidents. In this paper, color information of lane and road area is mapped to a 2-dimensional S-color space based on lane detection. And the center of the feature distribution is obtained by using an improved mean-shift algorithm in the S-color space. The lane color is determined by using the distance between the center coordinates of the color features of the left and right lanes and the road area. In various illumination conditions, about 97% color recognition rate is achieved.

• Proceedings of the Korean Society of Computer Information Conference
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• 2019.01a
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• pp.257-258
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• 2019

영상처리에 관한 다양한 오픈소스의 등장으로 현실의 사물을 인식하고 그에 따른 처리가 가능해졌다. 이에 따라 본 논문에서는 허프 변환 알고리즘을 이용하여 인식된 영상에서 효과적으로 차선을 검출하여 차량이 차선과의 거리를 일정하게 유지한 상태로 목적지까지 이동할 수 있게 하고, RFID를 이용하여 도착지점 알려주는 기술로 차선인식 자율주행 카를 개발하였다.

• Journal of Auto-vehicle Safety Association
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• v.5 no.1
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• pp.69-74
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• 2013

LKAS(Lane Keeping Assistance System) main function is to support the driver in keeping the vehicle within the current lane. Therefore, this system is able to reduce the driver workload with assisting the driver during driving. In this paper, we presented on study for test procedures and evaluation methods of the LKAS. The vehicle test conducted on straight road, left curve, right curve and four different types of lane under various vehicle speeds. This study proposed the LKAS system test procedures and methods that we are able to identify LKAS driving mechanism and performance.

• Transactions of the Korean Society of Automotive Engineers
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• v.17 no.3
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• pp.54-61
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• 2009

Lane keeping assistant system (LKAS) could save thousands of lives each year by maintaining lane position and is regarded as a promising active safety system. The LKAS is expected to reduce the driver workload and to assist the driver during driving. This paper proposes a model based predictive controller for the LKAS which requires cooperative driving between the driver and the assistance system. A Hardware-In-the-Loop-Simulator (HILS) is constructed for its evaluation and includes Carsim, Matlab Simulink and a lane detection algorithm. The single camera is mounted with the HILS to acquire the monitor images and to detect the lane markers. The simulation is conducted to validate the LKAS control performance in various road scenario.