• International Journal of Ocean Engineering and Technology Speciallssue:Selected Papers
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• 제4권1호
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• pp.31-37
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• 2001

In this paper, an integrated damage identification system (IDIS) is proposed to locate and size damage in real structures. The application of the IDIS to real structures includes the measurement of modal responses, the construction of damage-detection models, and the implementation of measurements and models into the damage-detection process. Firstly, the theory of the damage identification method is outlined. Secondly, the schematic and each component of the IDIS are described. Finally, the practicality of the IDIS is verified from experiments on two different bridge-models, a model plate-grider and a model truss.

• 한국소음진동공학회논문집
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• 제23권11호
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• pp.987-995
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• 2013

One of the most important processes to accurately predict structural responses is to evaluate accurate structural dynamic characteristics using finite element(FE) models. The numerical structural dynamic characteristics usually show considerable discrepancies with the measured ones because structural details are commonly simplified in the FE models. To identify such discrepancies, FE models of them have been calibrated using the measured dynamic characteristics in previous researches. In this study, the dynamic characteristics were measured for a historic cathedral and the FE model of it was calibrated using the measured results as a reference. Finally, a procedure of the FE model construction for the unreinforced masonry cathedral were tentatively proposed.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 추계학술대회논문집
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• pp.30-33
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• 2006

The purpose of this study is the improvement of the prediction model of highway noise. It includes the measurement and analysis of the highway noise for various types of roads and environments. The results of the measurement are compared with the noise levels predicted by highway noise prediction models including domestic and foreign ones and any recommendation to improve the accuracy of the models should be provided.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.69.1-69
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• 2001

In this paper, observability properties of a multiantenna GPS measurement system for the estimation of errors in INS are presented. It is shown that time-invariant INS error models are observable with measurements from at least three GPS antennas on the vehicle. There is at least one unobservable mode with two antennas. There are three unobservable modes with one antenna. It is also shown that time-varying INS error models are instantaneously observable with measurements from three GPS antennas. A numerical simulation results are given to verify the effectiveness of the multiantenna measurement system on the INS error estimation. In the simulation, a GPS measurement system is considered in which a trade-off between computational load and accuracy of estimation is achieved.

• Communications for Statistical Applications and Methods
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• 제2권1호
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• pp.1-12
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• 1995

An estimator of coefficients of polynomial measurement error model with vector predictor and first-order interaction terms is derived using Hermite polynomial. Asymptotic normality of estimator is provided and some simulation study is performed to compare the small sample properties of derived estimator with those of OLS estimator.

• 한국멀티미디어학회논문지
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• 제12권4호
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• pp.521-529
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• 2009

본 논문은 비전 기반 동작 인식 방법으로 모범 동작의 유형을 모형화하고 이를 이용하여 사용자의 동작을 인식하고 모범동작과 사용자의 동작간의 유사도를 측정하는 방법을 제안한다. 동작 인식을 위하여 은닉 마르코프 모델 기반의 유형화 기법을 통하여 모범 동작의 유형 모델을 구성하고 이를 이용하여 사용자의 동작을 인식한다. 유사도 측정을 위하여 편집 거리 알고리즘을 응용하여 모범 동작과 사용자 동작의 유사도를 측정하고 점수 표기가 가능하도록 하였다. 본 논문에서 제안하는 동작 인식 처리 방법은 평균 93% 이상의 높은 인식율을 보였다. 본 연구의 결과는 동작 인식 기반 게임, 자세인식, 동작의 반복 훈련 및 훈련 달성도 측정을 요하는 재활훈련 시스템 등에 활용 가능하다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제15권4호
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• pp.1193-1215
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• 2021

The measurement of the key product quality index plays an important role in improving the production efficiency and ensuring the safety of the enterprise. Since the actual working conditions and parameters will inevitably change to some extent with time, such as drift of working point, wear of equipment and temperature change, etc., these will lead to the degradation of the quality variable prediction model. To deal with this problem, the selective integrated moving windows based principal component regression (SIMV-PCR) is proposed in this study. In the algorithm of traditional moving window, only the latest local process information is used, and the global process information will not be enough. In order to make full use of the process information contained in the past windows, a set of local models with differences are selected through hypothesis testing theory. The significance levels of both T - test and χ² - test are used to judge whether there is identity between two local models. Then the models are integrated by Bayesian quality estimation to improve the accuracy of quality variable prediction. The effectiveness of the proposed adaptive soft measurement method is verified by a numerical example and a practical industrial process.

• 대한안전경영과학회지
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• 제11권3호
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• pp.209-216
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• 2009

A development in method of evaluating the measurement precisions using approximate F tests and variance components from expected mean square (EMS) is investigated. The research proposes three-factor mixed measurement models with the fixed and random factors. Unrestricted and unconstrained design work was rarely studied, while restricted and constrained designs have been significantly discussed. The unrestricted and unconstrained designs assume to be an independence of interaction. The proposed evaluation method about the measurement precisions can be extended to four-factor random measurement model or mixed measurement model. The study also presents the three evaluation indexes of precisions such as R&RTR (Reproducibility & Repeatability-To-Total Precision Ratio), PTR (Precision-To-Tolerance Ratio), and SNR (Signal-To-Noise Ratio). Numerical examples are proposed to evaluate the approximate F tests with Satterthwaite degrees of freedom and three indexes using the measurement precisions from EMS.

• Journal of Korean Dental Science
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• 제15권1호
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• pp.19-30
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• 2022

Purpose: The purpose of the study was to assess the validity of three-dimensional (3D) facial scan taken with facial scanner and digital photo wrapping on the cone-beam computed tomography (CBCT). Materials and Methods: Twenty-five patients had their CBCT scan, two-dimensional (2D) standardized frontal photographs and 3D facial scan obtained on the same day. The facial scans were taken with a facial scanner in an upright position. The 2D standardized frontal photographs were taken at a fixed distance from patients using a camera fixed to a cephalometric apparatus. The 2D integrated facial models were created using digital photo wrapping of frontal photographs on the corresponding CBCT images. The 3D integrated facial models were created using the integration process of 3D facial scans on the CBCT images. On the integrated facial models, sixteen soft tissue landmarks were identified, and the vertical, horizontal, oblique and angular distances between soft tissue landmarks were compared among the 2D facial models and 3D facial models, and CBCT images. Result: The results showed no significant differences of linear and angular measurements among CBCT images, 2D and 3D facial models except for Se-Sn vertical linear measurement which showed significant difference for the 3D facial models. The Bland-Altman plots showed that all measurements were within the limit of agreement. For 3D facial model, all Bland-Altman plots showed that systematic bias was less than 2.0 mm and 2.0° except for Se-Sn linear vertical measurement. For 2D facial model, the Bland-Altman plots of 6 out of 11 of the angular measurements showed systematic bias of more than 2.0°. Conclusion: The facial scan taken with facial scanner showed a clinically acceptable performance. The digital 2D photo wrapping has limitations in clinical use compared to 3D facial scans.

• 대한기계학회논문집A
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• 제34권1호
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• pp.73-78
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• 2010

재료의 인장 물성 측정 불확도 평가가 수행되었다. 인장 물성 측정에 영향을 주는 불확도의 요인이 구분되어 분석되었고 인장 시험으로부터 측정되는 측정량, 즉 탄성계수, 항복 강도 그리고 인장 강도의 불확도 평가 모델이 본 연구에서 제시되었고 각 측정량에 대한 대응하는 수학적 모델과 측정치로부터 각 측정치의 감도계수를 계산함으로서 유도 되었다. 각 모델에 근거하여 ISO 6892에 따라 결정되는 SUS316LN의 실험적 데이터로부터 인장 물성의 불확도가 평가되었다.