• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.7
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• pp.1292-1302
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• 2009

In this paper, we proposed Single Tone Detection Algorithm for prevent decoloration and color distortion of single tone image in auto white balance of mobile phone camera. Conventional auto white balance which accomplish very well using complex color images, but there are some problems if input images are single tone image or included large part of single tone. If input images are singlet one, or included large part of single tone, which cause decoloration or distorted color in output images. In this paper, we proposed single tone detection algorithm using color histogram data for solve decoloration or distorted color problems. If this algorithm is applied to auto white balance, it will be improvement in auto white balance.

• Journal of Korea Water Resources Association
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• v.45 no.12
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• pp.1213-1226
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• 2012

Evolutionary algorithms, which are frequently used in an automatic calibration of watershed runoff simulation models, are unconstrained optimization algorithms. An additional method is required to impose constraints on those algorithms. The purpose of the study is to modify the SCE-UA (shuffled complex evolution-University of Arizona) to impose constraints by a penalty function and to improve performance of the automatic calibration module of the SWMM (storm water management model) linked with the SCE-UA. As indicators related to peak flow are important in watershed runoff event simulation, error of peak flow and error of peak flow occurrence time are selected to set up constraints. The automatic calibration module including the constraints was applied to the Milyang Dam Basin and the Guro 1 Pumping Station Basin. The automatic calibration results were compared with the results calibrated by an automatic calibration without the constraints. Error of peak flow and error of peak flow occurrence time were greatly improved and the original objective function value is not highly violated in the automatic calibration including the constraints. The automatic calibration model with constraints was also verified, and the results was excellent. In conclusion, the performance of the automatic calibration module for watershed runoff event simulation was improved by application of the penalty function to impose constraints.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.39 no.6
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• pp.429-435
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• 2021

The integrated underground space map shows the underground facility(water supply, sewage, gas, electric power, communication, heating), underground structures (subway, underpass, underground walkway, underground parking lot, underground shopping mall, common ward), ground(drilling, coffin, geology) refers to a map constructed so that a total of 15 types of underground information can be checked at a glance on a three-dimensional basis. The purpose of this study is to develop a technology to correct the problem of curved surface processing and the unevenness of underground facility pipelines that occur in converting 2D underground facility data into 3D-based underground space integrated map(3D underground facility model). do it with. To this end, we first investigated and reviewed the domestic and foreign status of technologies that generate data on underground facilities based on three dimensions, and developed a surface correction algorithm and an unevenness correction algorithm to solve practical problems. Algorithms to verify the developed algorithm This applied correction program was developed. Based on the above process, the three-dimensional model of the underground facility could be produced identically to reality. This study is judged to have significance as a basic study to improve the utilization of the underground spatial integration map.

• Journal of the Institute of Convergence Signal Processing
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• v.14 no.2
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• pp.136-146
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• 2013

In this paper, the residual delay compensation algorithm is proposed for FX-type KJJVC. In case of initial version as that design algorithm of KJJVC, the integer calculation and the cos/sin table for the phase compensation coefficient were introduced in order to speed up of calculation. The mismatch between data timing and residual delay phase and also between bit-jump and residual delay phase were found and fixed. In final design of KJJVC residual delay compensation algorithm, the initialization problem on the rotation memory of residual delay compensation was found when the residual delay compensated value was applied to FFT-segment, and this problem is also fixed by modifying the FPGA code. Using the proposed residual delay compensation algorithm, the band shape of cross power spectrum becomes flat, which means there is no significant loss over the whole bandwidth. To verify the effectiveness of proposed residual delay compensation algorithm, we conducted the correlation experiments for real observation data using the simulator and KJJVC. We confirmed that the designed residual delay compensation algorithm is well applied in KJJVC, and the signal to noise ratio increases by about 8%.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2007.02a
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• pp.68-71
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• 2007

자연스러운 가상현실 제작을 위해서는 정확한 카메라 보정(camera calibration) 과정이 필수적인 선결 조건으로 요구된다. 그러나 기존의 영상처리에 의한 카메라 보정 방식은 특징점 추출에서의 에러 발생과 여러 장의 영상을 촬영해야 하는 등의 단점으로 줌렌즈 카메라 보정에는 사용되기 힘들었다. 본 논문에서는 카메라보정 객체의 모델에 기반하여 카메라 파라미터를 최적화하는 방법으로 카메라 보정을 구현하였다 최적화 방법으로는 경사기반 방식에 비해 국부최적점에 강인한 것으로 알려진 유전자알고리즘(genetic algorithm)을 사용하였다. 카메라 보정 객체에 낮은 공간주파수성분을 보강하고, 목적함수에 영상의 밝기 정보를 포함하며, 유전자알고리즘을 사용함으로써 초기치가 최적점에서 멀리 떨어져있는 경우에도 수렴이 가능함을 실험적으로 확인하였다.

• Journal of the Institute of Convergence Signal Processing
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• v.10 no.3
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• pp.151-157
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• 2009

In this paper, we proposed an algorithm of redeye correction. For naturally redeye correction, we assumed positions of the redeye at an image which produced redeye, and we estimated rate of the redeye to apply the appropriate redeye correction suitably. We extract and label pixels those are possible of generating redeye using red, skin and reflected light color. The each labeled group is decided by rates of length and width, dimension, density, the color of white of the eye and reflected light color of groups for the redeye group. We corrected positions of redeye using blurring effect, naturally. In the case of designing the proposed algorithm, we designed the redeye correction hardware using the minimum of memories for efficiency of hardware.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39C no.1
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• pp.9-16
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• 2014

The localization compensation algorithm for moving objects using the least-squares method is suggested and the performance of the algorithm is analyzed in this paper. The suggested compensation algorithm measures the distance values of the mobile object moving as a constant speed by the TMVS (TWR Minimum Value Selection) method, estimates the location of the mobile node by the trilateration scheme based on the values, and the estimated location is compensated using the least-squares method. By experiments, it is confirmed that the localization performance of the suggested compensation algorithm is largely improved to 58.84% and 40.28% compared with the conventional trilateration method in the scenario 1 and 2, respectively.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.539-539
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• 2012

최근 미국 환경부에서는 국가 환경 정책으로써 LID(Low Impact Development)를 대안 책으로 제시하고 있으며 우리나라에서도 최근 LID기법 연구가 활발히 진행 되고 있다. LID란 기존의 집중식 BMP처럼 유출 발생 후 처리를 다루는 방식의 기법이 아닌 발생원 단계에서의 처리에 초점을 맞춘 기법이다. 환경적 측면에서 다양한 기능을 가능하게 할 수 있는 LID기법 적용에 따른 효과를 알아보기 위해 전 세계적으로 SWMM 모형이 많이 사용되고 있지만 SWMM 모형 내 유량 및 수질에 따른 자동 보정 툴이 존재하지 않고 유역에 적합한 최적의 LID 기법 구조물의 설계 기준을 정할 수 있는 툴이 존재하지 않기 때문에 보다 효율적인 유역의 수문 보정 및 LID 기법 적용에 따른 효과 모의를 제공하지 못한다. 따라서 본 연구에서는 SWMM 5.0 버전 내 SWMM LID auto-calibration tool을 PARASOL 알고리즘을 기반으로 개발하였다. 또한 개발된 PARASOL 알고리즘 기반 SWMM LID auto-calibration tool을 이용하여 경기도 경안천 유역에 적용하였고 2011년 일별 실측 수문자료와 비교 분석 하였으며 경기도 경안천 유역에 맞는 최적의 LID기법을 산정하였다. 본 연구에서 개발 된 SWMM auto-calibration tool은 SWMM 모형의 유량 및 수질을 자동으로 보정하기 때문에 보다 효율적인 모형의 보정을 사용자에게 제공해 줄 수 있을 것이며 유역에 적합한 최적의 LID 기법 구조물 설계를 제시해 줄 수 있기 때문에 향후 LID 기법을 이용한 도시개발 계획에 유용하게 사용될 수 있을 것으로 판단된다. 향후 PARASOL 알고리즘 뿐만이 아닌 GLUE, SUFI-2, GA 등 다양한 알고리즘이 추가된 SWMM LID auto-calibration tool 을 개발 중에 있다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.6
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• pp.2263-2268
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• 2010

In this paper, the hybrid compensation algorithm($A_{HB}$) for localization using the Compensation Algorithm distance($CA_d$) and the Algorithm of Equivalent Distance Rate(AEDR) in SDS-TWR(Symmetric Double-Sided Two-Way Ranging) is suggested and the performance of the proposed algorithm is analyzed by practical experimentations. From experimentations, it is confirmed that the errors are reduced in 28 coordinates of total 32 coordinates in the experimental region and the errors are reduced about above 70% in the assigned 3 type error level ranges by $A_{HB}$. Also, it is analyzed that the average localization error is reduced from 2.67m to 1.19m as 55.4% in total 32 coordinates by $A_{HB}$ and the error compensation capability of $A_{HB}$ is very excellent as above 90%. From above results, we have seen that the error reduction ratio and error compensation capability of $A_{HB}$ is more excellent than each $CA_d$ or AEDR.

• Aerospace Engineering and Technology
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• v.5 no.2
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• pp.90-101
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• 2006

In this paper, the calibration parameters of the gyros and star hackers are estimated by using an on-orbit AOCS sensor calibration algorithm. The calibration algorithm was implemented by Kalman filter. In order to estimate gyro calibration parameters, the calibration algorithm requires calibration maneuver and it was analyzed whether the star trackers are protected by Sun, Moon and Earth or not. Also the star tracker calibration algorithm used the camera image information. This kinds of camera image information simulated ground control point and orbit information. The estimated accuracy of star tracker calibration parameters depends on camera image information.