• Proceedings of the Korea Society of Environmental Biology Conference
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• 2002.11a
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• pp.145-153
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• 2002

유해 화학 물질류에 의해 오염된 해양 환경 시료의 환경독성 수준을 평가하기 위하여 다양한 화학물질에 대해 민감성이 우수한 생물학적 독성평가기법을 개발 하고자하였다. 지속성 유기오염 물질 중 다환 방향 족 탄화수소(PAHs)를 처리한 광어(Conger myriaster)와 개조개(Saxidomus pupurata)의 DNA 손상정도를 single cell gel electrophoresis assay(comet assay)를 통해 분석하였다. PAHs 중 광양만에서 높은 농도로 검출되는 benzo(a)pyrene을 농도별(0, 10, 50, 100 ppb)로 처리한 후 2일과 4일에 광어의 혈액세포와 개조개의 근육세포를 채취해 comet assay를 실시하였다. benso(a)pyrene에 대한 DNA 손상정도를 처리된 농도와 생물종에 따라 다르게 나타났는데 광어의 혈액세포는 2일에 가장 DNA 손상정도가 높았고, 4일에는 회복되는 경향을 나타냈다. 개조개의 근육세포는 시간이 지나면서 DNA 손상정도가 증가하는 경향을 보였다. 이와 같은 결과는 comet assay 기법이 유해 화학물질로 오염된 해양생물 종의 환경독성을 검색하는 유용한 수단이 될 수 있음을 보여준다.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.34 no.2
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• pp.3-10
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• 2018

Damage location and extent of structure could be detected by the inverse analysis on dynamic response properties such as frequencies and mode shapes. In practice the measured difference of natural frequencies represent the stiffness change reliably, however the measured mode shape is insensitive for stiffness change, but provides spatial information of damage. The damage detection index on shear building structures is formulated in this study. The damage detection index could be estimated from mode shape and srory stiffness of undamaged structure and frequency difference between undamaged and damaged structure. For the verification of the observed damage detection method, the numerical analysis of Matlab and MIDAS and shacking table test were performed. In results, the damage index of damaged story was estimated so higher than undamaged stories that indicates the damaged story apparently.

• 한국HCI학회:학술대회논문집
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• 2009.02a
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• pp.547-551
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• 2009

In recent years, a film restoration has gained increasing attention by many researchers, to emergence of variety multimedia and to importance of video preservation. Blotch is the most frequent degradation in old film. This paper presents a blotch detection method using color and shape feature. The proposed method is two major modules: a SROD detector using impulsive feature and NN-based detector using shape feature. To assess the validity of the proposed method, the experiments have been performed on several old films.

• 전자공학회논문지 IE
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• v.45 no.2
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• pp.20-27
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• 2008

In this paper, we propose a new image processing technique that reliably detects the various defects of TFT-LCD polarizing films. The image of polarizing film is acquisited from reflected laser beam First, we apply the morphological image processing technique to remove the background noise. Next, we use the 2-dimensional LMS adaptive filtering and statistical characteristics to detect the white and black defects. Performance of the proposed method is evaluated on real TFT-LCD polarizing film samples.

• Journal of Welding and Joining
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• v.12 no.4
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• pp.35-40
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• 1994

비파괴검사(NDT)란 시험품에 손상을 주지 않고 내.외부에 존재하는 불연속부(결함)을 찾아내는 방법으로 다음과 같이 그 종류를 분류할 수 있다. (1) 표면결함 검출을 위한 비파괴검사 - 육안검사(VT) : 확대경 등에 의한 치수, 형상확인 - 자분탐상검사(MT) : 강자성체에 적용, 표면(하) 결함검출 - 침투탐상검사(PT) : 금속, 비철금속에 적용, 표면개구 결함검출 - 와류탐상검사(ET) : 도체 표층부(봉, 관 등) (2) 내부결함 검출을 위한 비파괴검사 - 방사선 투과검사(RT) : 결함의 종류, 형상의 판별 우수 - 초음파 탐상검사(UT) : 균열 등 면상 결함검출 등 우수 (3) 기타 비파괴검사 - Strain 측정 : 안전성 평가 - 음향방출시험(AET) - 누설시험(LT) - 중성자 방사선시험(NRT) 이상에서 보는 바와 같이 여러 종류의 비파괴검사가 있으나, 그 중에서 용접부에 적용되는 가장 일반적인 검사방법인 방사선 투과검사에 대해 기술하고자 한다.

• Proceedings of the Korean Information Science Society Conference
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• 2005.11b
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• pp.868-870
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• 2005

스크래치는 오래된 필름에서 가장 많이 나타나는 손상 요인이다. 고화질의 멀티미디어 서비스를 제공하기 위해서는 이러한 스크래치들은 반드시 검출 및 복원되어야 한다. 이러한 중요성 때문에 지금까지 많은 복원 알고리즘이 개발되어 왔으나, 스크래치 영역의 자동검출에 대한 연구는 거의 이루어지지 않은 실정이다. 따라서 본 논문에서는 자동으로 스크래치영역을 추출할 수 있는 신경망 기반의 검출 방법을 제안한다. 다층 퍼셉트론 (Multi-layer perceptron: MLP)을 이용하여 스크래치영역과 비 스크래치영역을 구분하는데, 이 MLP는 다양한 크기의 스크래치를 검출하기 위해 다양한 크기의 입력 영상에 대해 적용된다. 제안된 방법의 평가를 위해 principal/ secondary 스크래치, alone/not-alone 스크래치, moving/static 스크래치등의 다양한 종류의 스크래치를 가진 영상에 대해 실험이 이루어졌고, 그 결과 제안된 방법의 강건함과 효율성을 입증되었다.

• The Korean Journal of Food And Nutrition
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• v.22 no.4
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• pp.696-700
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• 2009

The adaptability of dry rehydratable film for the qualitative evaluation of coliform bacteria and Escherichia coli was tested. In general, culture methods that employ lactose broth or desoxycholate lactose agar are used for qualitative tests of coliform bacteria. Culture using lactose broth showed a high detection yield and low selectivity when compared to the dry rehydratable film. However, culture methods that employ lactose broth required a long time(48 hrs) for qualitative tests of coliform bacteria and complicated procedures were required to prepare the medium. The detection of coliforms using desoxycholate lactose agar had a slightly higher selectivity than the dry rehydratable film method, but this difference was not statistically significant. However, the preparation of the desoxycholate lactose agar was complicated. EC broth for the detection of E. coli showed the highest detection yield and lowest selectivity; however, this method required complicated procedures for preparation of the medium as well. Overall, the dry rehydratable film had a slightly lower detection yield than the other methods. The detection yield of dry rehydratable film method was over 37.1% at a concentration of 1 cfu/$m{\ell}$. Additionally, the dry rehydratable film method showed high selectivity and did not require preparation. However, because the selectivity of the dry rehydratable film was high, it took a long time(36 hrs) to detect E. coli. Overall, these findings indicate that dry rehydratable film can be used for qualitative detection of coliforms and E. coli.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.837-840
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• 1997

This paper provides an experimental verification of an FRF-based structural damage identification method (SDIM) developed by the authors for beam structures. The FRF-based SDIM requires the following data : (1) natural frequencies and mode shapes measured at the intact state and (2) the FRF-data measured at the damaged state. Experiments are conducted for the cantilevered beam with one slot and three slots. It is shown that the FRF-based SDIM developed by the authors provide very successful damage identification results which agree well with true damage state.

• Journal of the Korea institute for structural maintenance and inspection
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• v.11 no.2
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• pp.134-144
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• 2007

In this study, a smart sensor unit is developed by using the smart sensor technology that is being rapidly developed in recent years for structural health monitoring system, and its performance is evaluated through various experiments, and also, damage detection experiment is performed on a model structure. This paper as the first half of this study contains the development and performance evaluation of the smart sensor. In the latter half of this study, structure damage detection experiment is performed for the application of verified smart sensor unit into structural health monitoring, and it is compared with a wire measurement system. The smart sensor is developed by using high-power wireless modem, MEMS Sensor and AVR microcontroller, and an embedded program is also developed for the control and operation of the sensor unit. To verify the performance of the smart sensor, many experiments are performed for sensitivity and resolution analysis tests, data acquisition by using cantilever beam and shaker, and on-site application using actual bridge. As a result, the smart sensor proves to be satisfactory in its performance.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.43 no.6 s.312
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• pp.26-33
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• 2006

Film restoration is to detect the location and extent of defected regions from a given movie film, and if present, to reconstruct the lost information of each region. It has gained increasing attention by many researchers, to support multimedia service of high quality. In general, an old film is degraded by dust, scratch, flick, and so on. Among these, the most frequent degradation is the scratch. So far techniques for the scratch restoration have been developed, but they have limited applicability when dealing with all kinds of scratches. To fully support the automatic scratch restoration, the system should be developed that can detect all kinds of scratches from a given frame of old films. This paper presents a neurual network (NN)-based texture classifier that automatically detect all kinds of scratches from frames in old films. To facilitate the detection of various scratch sizes, we use a pyramid of images generated from original frames by having the resolution at three levels. The image at each level is scanned by the NN-based classifier, which divides the input image into scratch regions and non-scratch regions. Then, to reduce the computational cost, the NN-based classifier is only applied to the edge pixels. To assess the validity of the proposed method, the experiments have been performed on old films and animations with all kinds of scratches, then the results show the effectiveness of the proposed method.