• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.17 no.4
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• pp.373-381
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• 1999

Mobile Mapping System can be defined as vehicle mapping system which collects rapidly spatial data by integrated Gps/digital imaging system. Kinematic positioning by GPS is essential technology of Mobile Mapping System. This paper aims at analysing the accuracy and efficiency of kinematic positioning by GPS platformed on moving vehicle. For the purpose, roads were surveyed by vehicle/kinematic GPS. The results show that vehicle/kinematic GPS can measure spatial position faster, and still maintain a reasonable accuracy. But inertial navigation system and GPS should be integrated to compute continuous vehicle track and overcome gaps by blocked satellite signals for the more accurate positioning.

• Journal of KIISE:Databases
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• v.37 no.1
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• pp.33-43
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• 2010

In this paper, we propose a new location acquisition scheme based on RFID that reduces the computation cost of location acquisition and keeps the accuracy of the location. In addition, we propose an incremental location update policy to reduce the location update cost for moving objects. To show the superiority of our proposed scheme, we compare it with the existing researches. It is shown through various experiments that the proposed system reduces the computation cost of location estimation 500 times more than existing researches. Also, the proposed system significantly reduces the cost of location update using the RFID-based update policy.

• Journal of the Korean Institute of Intelligent Systems
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• v.26 no.4
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• pp.321-326
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• 2016

In this paper, we propose a luminance correction algorithm based on measuring position for potable luminance measurement system. Measurement position and angle have an affect on the luminance value. We improve the position-based luminance measurement system using luminance correction algorithm based on the measuring angle. We analyze change of luminance value according to the measurement distance and angle from camera and light source. The certified point-luminance meter is used to evaluate a scene luminance measuring method using the image information of camera. Also, we derive an expression equation for evaluating luminance value from determined position. The performances of the proposed system are verified by using comparative experiments with the point-luminance meter using experimental signboard.

• Journal of the Korean Society of Radiology
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• v.14 no.6
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• pp.725-731
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• 2020

A radiation spectroscopy detector using a spherical scintillator was designed, and a system was developed to track the position of a radiation source using several detectors. The position tracking algorithm was designed based on the theory that the number of radiations decreases according to the inverse square law of distance, and the position of the radiation source was calculated by measuring the number of radiations generated from the radiation sources at various positions. The radiation generated from the radiation source is detected by different coefficients in each detector, and the difference between these detected coefficients varies in proportion to the inverse square of the distance. Geant4 Application for Tomographic Emission (GATE) simulation was performed to verify and evaluate the performance of the designed radiation source position tracking system, and radiation generated from radiation sources placed at different positions was counted with each detector. The number of measured radiations was tracked through the radiation source position tracking algorithm, and the error between the actual radiation source position and the position calculated by the algorithm was evaluated. The error between the position of the actual radiation source and the calculated position was measured as an average of 0.11% on the X-axis and 0.37% on the Y-axis, and it was verified that the position can be measured very accurately.

• Proceedings of the IEEK Conference
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• 1998.06a
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• pp.255-258
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• 1998

이동로봇이 움직이는 물체를 추적하는 기능을 갖도록 하기 위해서는 움직이는 물체의 존재를 판단하고 위치 및 속도벡터를 측정해야 한다. 본 논문은 단시간에 이동 물체의 위치와 속도벡터 추정하여 실시간 추적이 가능하도록 하기 위해 초음파센서를 이용한 가상의 초음파영상 해석방법을 제안한다. 초음파 영상은 초음파센서의 매회 측정값을 누적하여 구성하며 거리축과 시간축을 갖는 2차원 영상으로 표현된다. 영상에서 측정된 물체가 만드는 선분의 기울기에 따라 이동하는 물체와 정지한 물체를 분리하고 속도를 측정한다. 제안된 방법은 시뮬레이션을 통해 타당성을 입증하였다.

• Proceedings of the Korea Contents Association Conference
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• 2010.05a
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• pp.274-276
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• 2010

WADGPS 또는 Beacon DGPS를 이용하여 해상준설선의 유도와 측량을 위한 실시간 준설관리시스템을 구축하고자 하였다. 이 시스템은 GPS에 의한 선박위치측정, GPS/Gyro 통합장비에 의한 선박방향측정, 그라브 위치측정, 준설심도측정 및 보정의 기능을 갖도록 하였다. 또한 구축된 준설공정관리시스템을 제어 운용하기 위한 프로그램을 개발하였다.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05d
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• pp.139-146
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• 1996

도로건설시 다짐조절은 안정성과 내구성 향상에 중요한 의미를 가지며 이러한 다짐조절에 있어서 수분함량의 측정은 매우 중요하다. 이전에는 흙의 수분함량을 측정하기 위한 계기를 설계하기 위하여 주로 실험에 의한 방법을 사용하였으나 본 연구에서는 3차원 모델링이 가능한 MCNP코드$^{(1)}$ 를 이용하여 계측기 설계에 있어서 중요한 설계변수인 방사선원의 위치와 측정계기 사이의 거리 그리고 계기구성요소인 검출기의 위치, 개수, 흡수재, 감속재의 기하학적 구조 등을 계산하여 설정하였다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 1999.04a
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• pp.25-25
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• 1999

안정화 화염으로 수소 확산 화염을 이용한 메탄/공기 난류 예혼합 화염의 미연가스 영역의 난류 특성을 측정하였다. 측정은 동일한 위치에 대해서 화염이 존재할 때와 존재하지 않을 때에 대해 수행되었다. 버너 출구 레이놀즈 수 7000에서 당량비 0.6과 1.0의 경우에 대해 실험이 수행되었다. 난류 유동장은 2색 레이저 유속계에 의해 측정되었다. 21개의 위치에 대해서 반복적으로 측정이 수행되었다.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.1
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• pp.121-131
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• 2015

Passive emitter localization is preferred to use a small number of receivers as possible for the efficiency of strategic management in the field of modern electronic warfare support. Accurate emitter localization can be expected when utilizing continuous measurable parameters and a appropriate combination of theirs. For this reason, we compare CRLB (Cramer-Rao lower bound) of two moving platform with various measurable parameters to choose a appropriate combination of parameters for a better localization performance. And we propose the passive emitter localization method based on Levenberg-Marquardt algorithm with combined TDOA/FDOA and DOA to achieve better accuracy of emitter localization which is located on the ground and stationary. In addition, we present a method for determining the initial emitter position for LM algorithm's input to avoid the divergence of estimation and local minimum.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.4B
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• pp.309-316
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• 2012

The compensation algorithm for localization using the least-squires method in NLOS(Non Line of Sight) environment is suggested and the performance of the algorithm is analyzed in this paper. In order to improve the localization correction rate of the moving node, 1) the distance value of the moving node that is moving as an constant speed is measured by SDS-TWR(Symmetric Double-Sided Two-Way Ranging); 2) the location of the moving node is measured using the triangulation scheme; 3) the location of the moving node measured in 2) is compensated using the least-squares method. By the experiments in NLOS environment, it is confirmed that the average localization error rates are measured to ${\pm}1m$, ${\pm}0.2m$ and ${\pm}0.1m$ by the triangulation scheme, the Kalman filter and the least-squires method respectively. As a result, we can see that the localization error rate of the suggested algorithm is higher than that of the triangulation as average 86.0% and the Kalman filter as average 16.0% respectively.