• 한국도로학회논문집
• /
• 제18권5호
• /
• pp.63-73
• /
• 2016

PURPOSES : The objective of this study was to analyze variations in the vehicle driving behavior characteristics on signalized intersections according to the use of traffic enforcement camera (red light camera). METHODS : In order to analyze the driving behavior characteristics on signalized intersections when red light camera are installed, the target sites for investigation were selected depending on whether the red light camera is installed and accident rates increased after the installation. In particular, to analyze the characteristics of dilemma zones in signalized intersections, approach speed and deceleration speed of 3 type vehicles (passing vehicles during a yellow light, stopping at a yellow light, passing vehicles during a green light) were examined. Based on these data, the starting point, ending point, and distance of the dilemma zones were calculated. Also, the locations of increased traffic accidents and decreased accidents after the installation of the equipment were distinguished when analyzing the traffic accident characteristics. RESULTS : Analysis results revealed that there was a tendency for the dilemma zone distance to decrease after the installation of equipment(red light camera) in most sites. This tendency was found to be due to the decrease in the approaching speed of vehicles at intersections after the installation of equipment, resulting in the starting and ending points of dilemma zone to become closer to the stop line. Moreover, analysis showed that the number of traffic accidents decreased for most intersections after the installation of equipment and safety of the intersections increased somewhat. CONCLUSIONS : In general, installation of equipment(red light camera) caused the intersections approaching speed and dilemma zone distance to decrease. Decision-making is difficult for drivers in the dilemma zone, so the decrease in the dilemma zone distance implies an improvement in traffic safety. Furthermore, the number of accidents within intersections significantly decreased after the equipment was installed, leading to the conclusion that installation of the equipment affected the decrease in traffic accidents.

• 한국도로학회논문집
• /
• 제17권1호
• /
• pp.119-127
• /
• 2015

PURPOSES : Before-and-after studies of red light cameras were conducted with the aim of reducing the number of side right-angle collisions. Three different methods were used for the before-and-after studies, and the analysis results were compared. METHODS : This research used the naive before-and-after method, the comparison-group method, and the empirical Bayes method to study the effects of red light cameras on side-angle collisions. The results of the three before-and-after methods were compared and interpreted in terms of safety indications at signalized intersections. RESULTS : The research results showed that side right-angle collisions can be reduced by installing red light cameras at signalized intersections. All three methods guarantee safety improvements of 25~30% on average. With regard to the results of each method, the naive before-and-after method, the comparison-group method, and the empirical Bayes method showed safety improvements of 25.6%, 27.8%, and 29.7%, respectively. CONCLUSIONS : It was concluded that red light cameras are an effective countermeasure to improve intersection safety. In particular, by installing red light cameras, side right-angle collisions can be reduced by up to approximately 25~30%.

• 한국도로학회논문집
• /
• 제14권6호
• /
• pp.67-73
• /
• 2012

PURPOSES : This study deals with the effects on the installation of RLC(Red Light Camera). The objective is to analyze the effects of accident reduction after the installation of RLC. METHODS : In pursuing the above, the study uses the 703 accident data occurred at the 64 intersections which RLC are installed or not installed. RESULTS : The main results are as follows. First, Poisson RLC accident model developed in this study is analyzed to be statistically significant. Second, using the above developed model, 33 intersections among 40 intersections are predicted to have the decreasing effects of accidents after the installation of RLC. Finally, the reduction effects are analyzed to be affected by ADT and the number of left-turn lane. CONCLUSIONS : This study is expected to improve the efficiency of RLC and to help in decision-making of RLC installation.

• 제어로봇시스템학회논문지
• /
• 제14권8호
• /
• pp.767-773
• /
• 2008

This paper presents a localization system based on the use of electric compass and tracking IR light source. Digital RGB(Red, Green, Blue)signal of digital CMOS Camera is sent to CPLD which converts the color image to binary image at 30 frames per second. CMOS camera has IR filter and UV filter in front of CMOS cell. The filters cut off above 720nm light source. Binary output data of CPLD is sent to DSP that rapidly tracks the IR light source by moving Camera tilt DC motor. At a robot toward north, electric compass signals and IR light source angles which are used for calculating the data of the location system. Because geomagnetic field is linear in local position, this location system is possible. Finally, it is shown that position error is within ${\pm}1.3cm$ in this system.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2002년도 ICCAS
• /
• pp.115.5-115
• /
• 2002

In this paper, we introduce a system that detects all kinds of violations at a street intersection such as red light running, speed violation, stop line violation and lane violation by tracking individual vehicles. Two cameras are used for defecting violations. One is an analog camera for real-time tracking and the other is a digital camera for license plate reading. This system is connected to the traffic signal system controller and monitors the red, arrow, yellow and green phases of an approach. Two loops in the road are used to detect vehicle approach and speed. The system takes pictures of all vehicles passing a second loop and tracks the vehicles until they go out a street intersection...

• 한국측량학회지
• /
• 제38권6호
• /
• pp.707-716
• /
• 2020

원격탐사 분야에서 물체의 특성을 정략적으로 추정할 수 있는 분광센서에 대한 관심이 늘어나고 있으며, 특히, 최근 드론에 탑재하여 운영할 수 있는 경량 다분광 카메라의 활용이 주목받고 있다. 정량적 원격탐사를 위해서는 카메라 또는 센서에서 획득된 복사량의 정확도가 중요하지만, 저가의 다분광 카메라의 경우 복사정확도에 대한 독립적인 검증이 충분히 수행되지 않았다. 본 연구에서는 최근 농작물 모니터링, 식생 분석, 수질 분석 등에 다양하게 활용되고 있는 MicaSense사의 RedEdge-MX 카메라에 대한 복사 정확도 분석을 수행하였다. 미국 NIST 표준에 따라 교정된 초분광 센서인 TriOS RAMSES를 이용하여, RedEdge-MX 센서의 복사휘도 및 복사조도에 대한 상대 보정계수를 산출하였다. 분석결과, RedEdge-MX의 복사휘도는 밴드별로 RAMSES보다 5~16% 가량 낮게 나타났고, 복사조도 역시 1~20% 가량 낮은 것이 확인되었다. 본 연구에서는 RedEdge-MX의 관측값을 RAMSES에 상응하는 값으로 변환시키기 위한 보정계수를 1차 그리고 3차 회귀분석을 통하여 제공한다.

• 한국도로학회논문집
• /
• 제12권3호
• /
• pp.49-57
• /
• 2010

본 연구는 충북도내 도심부/도시외곽부/지방부 신호교차로에서의 신호위반에 관한 것이다. 연구의 목적은 신호위반과 다양한 인적, 차량 및 도로환경요인의 관계를 이해하고자 함에 있다. 본 연구의 기술통계와 로지스틱 분석을 위해서 SPSS 12.0을 이용하였다. 분석된 주요 결과는 다음과 같다. 첫째, 신호위반은 도시외곽부보다는 지방부와 도심부에서 많이 발생하는 것으로 분석되었다. 둘째, 신호위반 운전자의 81.1%가 제한속도 이하로 주행하였으며, 77.3%는 적색등화후 2.0초 이내에 교차로에 진입하다 단속되었다. 마지막으로, 로지스틱 회귀분석에 의해 통계적으로 유의한 모형식이 개발 되었다(chi-square=0.000, McFadde=0.265). 개발된 모형의 독립변수로는 지역(도심부/도시외곽부/지방부), 운전자 성별, 계절, 차종, 주야간, 주행속도를 포함하고 있다. 본 연구에서는 신호위반 운전자의 연령과 신호교차로 접근부에서의 운전행태 간의 밀접한 관련성은 발견하지 못하였다.

• 한국도로학회:학술대회논문집
• /
• 한국도로학회 2010년 춘계학술대회 논문집
• /
• pp.159-166
• /
• 2010

• Journal of the Optical Society of Korea
• /
• 제20권6호
• /
• pp.784-793
• /
• 2016

We present a single shot low coherence white light Hilbert phase microscopy (WL-HPM) for quantitative phase imaging of Si optoelectronic devices, i.e., Si integrated circuits (Si-ICs) and Si solar cells. White light interferograms were recorded by a color CCD camera and the interferogram is decomposed into the three colors red, green and blue. Spatial carrier frequency of the WL interferogram was increased sufficiently by means of introducing a tilt in the interferometer. Hilbert transform fringe analysis was used to reconstruct the phase map for red, green and blue colors from the single interferogram. 3D step height map of Si-ICs and Si solar cells was reconstructed at multiple wavelengths from a single interferogram. Experimental results were compared with Atomic Force Microscopy and they were found to be close to each other. The present technique is non-contact, full-field and fast for the determination of surface roughness variation and morphological features of the objects at multiple wavelengths.

• 한국안전학회지
• /
• 제32권6호
• /
• pp.98-103
• /
• 2017

In Korea, the guideline for the bridge safety inspection requests to assess surface degradation, including crack, efflorescence, spalling, and so on, for the rating of concrete bridges. Currently, the assessment of efflorescence is performed based on the visual inspection of expertized engineers, which may result in subjective inspection result. In this study, a novel method using a hyperspectral camera is proposed for objective and accurate assessment of concrete efflorescence. The hyperspectral camera acquires the light intensity for a number of continuous spectral bands of light for each pixel in an image, which makes the hyperspectral imaging technique provides more detailed information than a color camera that collects intensity for only three bands corresponding to RGB (red, green, and blue) colors. A stepwise assessment algorithm is proposed based on the spectral features to decompose efflorescence area from the inspected concrete area. The algorithm is tested in the laboratory test using two concrete specimens, one of which is dark colored with efflorescence on a surface while the other is bright concrete without efflorescence. The test shows high accuracy and applicability of the proposed efflorescence assessment using a hyperspectral camera.