• International Journal of Highway Engineering
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• v.9 no.1 s.31
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• pp.29-38
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• 2007

The Korea National Police Agency launched a campaign to encourage drivers in stop line observance and to discourage stop line violation by intensively imposing fines. It was to increase stop line observance of drivers and thus traffic safety. According to statistics, the stop line observance rate was increased over 80 % of drivers during the campaign but regressed to the past after the campaign. This paper delivers the effect of the location of traffic signal lights on driver's stop line observance and develops a guideline to improve highway traffic environment in long terms. Statistical tests conducted based on field data showed that the drivers' stop line observance increases when traffic signal lights are closely installed from a stop line. It was proposed from the study that traffic signal lights be installed $10{\sim}20m$ from a stop line.

• Journal of Korean Society of Transportation
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• v.26 no.1
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• pp.7-14
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• 2008

One of purposes of installing signals at intersections is to protect traffic conflicts and accidents from occurring by means of arranging the right-of-way of travel more clearly. On the other hand, the installation of signals, and especially their location, can also have negative effects on safety. Therefore, the location of signals is of great importance. To secure a high safety level for urban signalized intersection, efforts are required to introduce a comprehensive recommendation or guideline for safety aspects of signal installation that takes local conditions into account. In this context, this reports on a study that analyzed the influence of signal location on the behavior of drivers who approach a signalized intersection in urban area. As a result, the study found out that the traffic signal location strongly affects the braking point of the Dilemma Zone(DZ), and the braking point of the DZ based on driving speed. Also, in terms of design layout, it has been illustrated that there is a close relation between signal location and road safety, especially DZ safety. Finally, this paper proposes a practical recommendation for signal installation related to how to locate the signal in practice for the sake of securing the safety level of signalized intersection.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.14 no.5
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• pp.12-18
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• 2000

This paper describes the analysis of ultrasonic signal and partial discharge(PD) signal patterns for each location of particle in GIS. The characteristics of the ultrasonic signal and PD signal patterns for each location were as follows; in case of particle on the electrode, large ultrasonic signals and large PD signals occurred in positive half-cycle periodically; in case of particle on the spacer, ultrasonic signals and large PD signals occurred in negative half-cycle periodically; in case of the free moving particle, ultrasonic signals and large PD signals occurred by collision non-periodically. As a result, it was confirmed that particle in GIS could be located by the comparison and analysis of ultrasonic signal and PD signal patterns.

• Proceedings of the Acoustical Society of Korea Conference
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• spring
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• pp.261-264
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• 2000

음향센서의 정확도 시험을 위해서는 사전 약속된 모의신호를 발생하는 기준 음향센서, 즉 모의신호 발생기가 필요하다. 모의신호 발생기는 정확도 시험의 기준이 되므로 위치가 정확하게 산출되어야 하고, 발생시키는 모의신호는 시험 목적에 부합되도록 설계되어야 한다. 본 연구에서는 모의신호 발생기의 위치 추정 및 모의신호 발생을 위한 설계 기법을 제안하고, 제안 기법에 대한 위치 추정 알고리즘을 시뮬레이션으로 고찰한다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.8C
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• pp.605-612
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• 2008

This paper researches the estimating location using repeater effect adjustment method in CDMA based system. Repeaters are commonly used by commercial and amateur radio operators to extend signals in the radio frequency range from one receiver to another. The repeater signals are increasing arrival time from base station to mobile station. So if we calculates the mobile station using repeater signals, the estimating position error is increased. However nobody researched about adjusting repeater effects. This paper proposes repeater effect adjustment algorithm. For adjusting repeater effects, we make the triangle using mobile station, reference base station and neighbor base station, and then detect the repeater effects using the triangle characteristic. The proposed method system showed the improved performance in estimating parameters and locating positions by computer simulations.

• The Journal of the Korea institute of electronic communication sciences
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• v.17 no.4
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• pp.571-576
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• 2022

Due to the epochal development of the unmanned technology, the importance of LDT(: Location Detection Technology), which accurately estimates the location of a user or object, is dramatically increased. TOA(: Time of Arrival), which calculates a location by measuring the arrival time of signals, and TDOA(: Time Difference of Arrival) which calculates it by measuring the difference between two arrival times, are representative LDT methods. Based on the signals received from three or more base stations, TOA calculates an intersection point by drawing circles and TDOA calculates it by drawing hyperbolas. In order to improve the radio shadow area problem, a huge number of repeaters have been installed in the urban area, but the signals received through these repeaters may cause the serious error for estimating a location. In this paper, we propose an efficient location estimation technique using the signal received through the repeater. The proposed approach estimates the location of MS(: Mobile Station) employing TOA and TDOA methods, based on signals received from one repeater and two BS(: Base Station)s.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.5
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• pp.55-63
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• 2013

In cognitive radio networks, acquirement of position information of primary user is very important to secondary network since localization information of primary users can be utilized for improving the spectrum efficiency of secondary network and for avoiding harmful interference to primary users by using proper power control. Among various location methods, Received Signal Strength (RSS)-based localization has been widely used for distance measurements in the location detection process despite its inherent inaccuracy because it can be easily implemented without any additional hardware cost. In the RSS-based localization, the distance is measured by the received signal strength, and distance error can be caused by many factors such as fading, shadowing and obstacle between two nodes. In the paper, therefore we propose a localization scheme based on estimation of path-loss exponent to localize the location of primary users more accurately. Through simulations, it is shown that the proposed scheme can provide less localization error and interference rate to primary users than other schemes.

• The Journal of the Acoustical Society of Korea
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• v.12 no.2E
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• pp.73-79
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• 1993

전력수요의 증가에 따라 전력계통의 대규모, 고엊압화 되는 현실에서 변압기의 사고는 사회여러분야에 큰 영향을 주게 되었다. 이에 세계 여러나라에서는 변압기 사고 예방진단시스템을 연구하고 있으며 일부는 실제 설치, 운영중에 있다. 본 논문에서는 변압기사고진단의 일환으로 변압기 사고의 원인이 되는 부분방전을 제거할 때 방전점을 예측하여 비용과 시간을 줄이고자 하였다. 부분방전의 위치를 예측하는 방법으로 2개의 초음파 신호의 신호상관법을 이용하였으며 모의 변압기를 통한 실험에서 오차가 4%이하로 비교적 정확한 위치 예측이 가능함을 보여 주었다.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1130-1131
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• 2007

레졸바는 엔코더에 비하여 가격면에서 유리하지 않다. 그러나 절대위치를 검지해야 하는 경우와 기계적으로 견고해야 하는 장소에서 정교한 제어에 사용되고 있다. 레졸바에 의한 위치와 속도검출 방법은 일반적으로 관측기를 응용하고 있으며 아날로그신호를 처리해야 하는 부분을 갖고 있다. 본 연구에서는 레졸바의 출력신호를 위치정보인 cos과 sin파형으로 복조하고 복조된 아날로그신호를 제어기에 전송하는 방법을 사용하였다. 제어기의 프로그램에 추정기를 설계하고 극 저속에서 그 동작을 관찰하였다.

• Proceedings of the KIEE Conference
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• 2005.07e
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• pp.85-87
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• 2005

변압기의 진단을 위한 부분방전 측정방법 중 전자파를 이용한 방법은 실시간 측정이 가능하고 감도가 좋으며 외부노이즈에 강한 장점이 있어 매우 유망하다. 이러한 상황에서 단순한 부분방전의 측정뿐 아니라 나아가 변압기 내부의 부분방전 위치를 탐지 할 수 있다면, 변압기의 신속한 유지보수에 기여할 수 있을 것이다. 하지만 도체로 이루어진 변압기 외함 및 내부 구조물에 의한 공진 현상과, 결함에 따라 다른 스펙트럼의 부분방전 신호로 인하여 단일대역의 전자파 센서로는 위치탐지의 신뢰성이 떨어진다. 이에 본 논문에서는 위치 탐지용 다중대역 센서를 개발하였으며, 변압기 내부의 구조물 유무 및 부분방전 위치에 따른 신호를 분석하였다.