• 대한전기학회논문지:시스템및제어부문D
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• 제54권3호
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• pp.191-193
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• 2005

This paper proposes a phase measurement algorithm which is based on the recursive implementation of sliding-DFT. The proposed algorithm is designed to have a robust behavior against the erroneous factors of frequency drift, additive noise, and twiddle factor approximation. Four channel power-line phase measurement system is also designed and implemented based on the time-multiplexed sharing architecture of the proposed algorithm. The proposed algorithm's features of phase measurement accuracy and its robustness against the finite wordlength effects can provide a significant impact especially for the ASIC or microprocessor based embedded system applications where the enhanced processing speed and implementation simplicity are crucial design considerations.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 A
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• pp.92-94
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• 2003

The design of a measurement system to perform Harmonic State Estimation(HSE) is a very complex problem. In particular, the number of available harmonic instruments (Continuous Harmonic Analysis in Real Time : CHART) is always limited. Therefore, a systematic procedure is needed to design the optimal placement of measurement points. This paper presents an optimal algorithm of HSE which is based on an optimal placement of measurement points using Immune Algorithm (IAs). This HSE has been applied to power system for the validation of an optimal algorithm of HSE. The study results have indicated an economical and effective method for optimal placement of measurement points using IAs in the HSE.

• 전기학회논문지
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• 제57권4호
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• pp.677-685
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• 2008

This paper proposes algorithm for the obstacle detection and classification using a single laser scanner. In a measurement data from a laser scanner, there exist points with large differential value called singular points, which can be used to obtain the boundary of an obstacle such that obstacle information can be analyzed. On the other hand, measurement data include a lot of measurement error, which makes it difficult to analyze the accurate obstacle information. To solve this problem, the least square estimation algorithm is used to obtain the accurate information using a single laser scanner, by compensation for the measurement error. This algorithm can be used for the effective obstacle avoidance of mobile robots, and the experimental results are included to demonstrate the effectiveness of the propose algorithm.

• 대한전자공학회논문지SP
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• 제42권1호
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• pp.109-117
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• 2005

거리 및 속도 측정 알고리즘은 거리 및 도플러 주파수 영역에서 등 간격으로 구성된 정합필터 출력을 이용하여 정밀한 표적 위치를 추정하는 과정이다. 특히 다기능 레이다용 측정 알고리즘은 동시에 다 표적 추적이 가능하도록 정밀도 뿐만 아니라 수행시간에 대한 고려가 필요하다. 본 논문에서는 모노 펄스(monopulse) 레이다 각도추정에 사용되는 변별기(discriminator)추정방식을 거리 및 속도 측정에 적용하여 알고리즘 성능분석 결과를 제시한다. 적용된 추정방법은 추정 시 수행시간이 일정하므로 다중 표적 추적에 적합하다. 하지만 최소한의 채널 출력만을 이용한 추정방법이므로 측정 정밀도에 대한 고려가 필요하다. 컴퓨터 모의실험을 통해 기존 무게중심 추정방식의 측정 알고리즘과 정밀도 측면에서 성능을 비교하여 적용한 방법의 우수성을 보이고, 또한 펄스 폭, 채널 간격 등 프로세싱 변수 변화에 따른 RMS 에러 계산을 통해 알고리즘 자체 특성을 분석한다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 추계학술대회논문집
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• pp.1382-1385
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• 2007

In this paper, we study about the measuring algorithm that can implement Structural Health Monitoring (SHM) more efficiently by two measurement methods using smart sensor. Through the impedance measurement method, the damage condition of structures on wide area is monitored first, and then it changes the mode to guided wave measurement mode by mode switching algorithm when impedance measurement mode detects abnormal signals. Efficient handling of the real-time data would be available by analyzing location and shape of damage through guided wave measurement.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 신호처리소사이어티 추계학술대회 논문집
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• pp.493-496
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• 2003

Recently, Ryu et al. proposed a multiple target DOA tracking algorithm, which has good features that it has no data association problem and simple structure. But its performance is seriously degraded in the low signal-to-noise ratio. In this paper, a measurement fusion method is presented based on ML(Maximum Likelihood), and the new DOA tracking algorithm is proposed by incorporating the presented fusion method into Ryu's algorithm. The proposed algorithm has a better tracking performance than that of Ryu's algorithm, and it sustains the good features of Ryu's algorithm.

• 한국정밀공학회지
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• 제20권10호
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• pp.120-129
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• 2003

For successful establishment of the roughing CAM system based on reverse engineering, it is necessary to develop the measurement method for generation of roughing path from a physical footwear model. In this study, the development of the roughing path measurement system is presented. It consists of 3 CCD cameras, image acquisition board and the roughing path measurement algorithm. The 3 CCD cameras capture images of the sidewall and the bottom of the footwear and, from two images, the outer and inner lines are extracted using image-processing algorithm. The roughing path measurement algorithm generates the roughing path which is reflected on the change of resolution according to the distance between the CCD camera and the measured point. The experimental results show that the developed system can measure the roughing path within the allowable roughing error range.

• 한국건설관리학회논문집
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• 제24권2호
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• pp.70-78
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• 2023

선행연구에서는 지중경사계의 문제점인 1) 지중경사계관 설치의 어려움, 2) 단면 변위 파악의 한계성, 3) 인력 중심의 계측 방식을 해결하기 위한 2D LiDAR 센서 기반의 흙막이 벽체 변위 계측 시스템을 개발하였다. 본 연구의 목적은 선행연구에서 개발된 흙막이 벽체 변위 계측 시스템 내 탑재될 변위 분석 알고리즘을 선정하는 것이다. 변위 분석 알고리즘 선정 결과, 변위 추정 오차가 2mm인 M3C2 알고리즘이 흙막이 벽체 변위 분석 알고리즘으로 선정되었다. 본 연구 결과에서 선정된 M3C2 알고리즘이 흙막이 벽체 변위 계측 시스템에 탑재되고 수차례의 현장 실험을 통해 변위 분석 결과의 신뢰성이 담보될 경우 흙막이 벽체 변위 계측 시스템이 현행 계측관리 대비 변위 계측의 편리성 측면에서 효과적으로 흙막이 벽체의 변위를 관리할 수 있을 것으로 판단된다.

• 한국분무공학회지
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• 제6권1호
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• pp.35-43
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• 2001

Previous studies on image processing techniques for panicle size measurement usually have focused on a single panicle or weakly overlapped particles. In the present work, the image processing algorithm for particle size measurement has been improved to process heavily-overlapped spherical-particle images. The algorithm consists of two steps; detection of boundaries which separate the images of the overlapped panicles from the background and the panicle identification process. For the first step, Sobel operator (using gray-level gradient) and the thinning process was adopted, and compared with the gray-level thresholding method that has been widely adopted. In the second, Hough transform was used. Hough transform is the detection algorithm of parametric curves such as straight lines or circles which can be described by several parameters. To reduce the measurement error, the process of finding the true center was added. The improved algorithm was tested by processing an image frame which contains heavily overlapped spherical panicles. The results showed that both the performances of detecting the overlapped images and separating the panicle from them were improved.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 추계종합학술대회 논문집
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• pp.507-510
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• 1999

Inspection of BGAs presents several challenges for modem measurement equipment. No only must these systems be fast and accurate, they must deal with the special challenges presented by very small shiny metal spheres. For accurate measurement, we propose an algorithm which fits for estimating the accurate ball height using 2-D curve-fitting algorithm. The real boundary between two adjacent pixels and the real ball diameter are measured with subpixel accuracy Experimental results show that the proposed method calculates the ball height and diameter with subpixel accuracy and is robust in local noise with low measurement error.