• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2012년도 춘계학술대회 논문집
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• pp.734-738
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• 2012

A comprehensive vibration assessment program for the Advanced Power Reactor 1400 reactor vessel internals is established in accordance with the United States Nuclear Regulatory Commission Regulatory Guide 1.20 Revision 3. This paper is related to instruments and measurement locations based on the vibration and stress response analysis results at the inner barrel assembly top plate in the reactor. The analysis results of the inner barrel assembly top plate in the reactor show that the deterministic stress and deformation due to the reactor coolant pump induced pressure pulsations are larger than the random stress and deformation induced by the flow turbulence. The selection of the instruments and measurement locations at Inner barrel assembly top plate in the reactor is essential requirements and very important study process for the vibration and stress measurement program in comprehensive vibration assessment program for the Advanced Power Reactor 1400 reactor vessel internals.

• 조명전기설비학회논문지
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• 제20권4호
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• pp.12-20
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• 2006

중화학 공업은 전해조를 포함한 비선형 부하를 가지고 있다. AC-DC 컨버터로 구성된 전해조는 고조파 전류를 발생시키고, 전력 계통의 전압을 왜곡 시킨다. 본 논문에서는 전해조 부하의 고조파 현장 측정, 고조파 저감을 위해 수용가 모선에 동조 필터 적용과 국제 고조파 관리 기준인 IEC 61000-3-6과 IEEE 519에 의한 고조파 평가를 심도있게 분석한다. 고조파 해석 프로그램인 EDSA는 사례연구에 시뮬레이션 도구로 사용되었다.

• 보존과학연구
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• 통권31호
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• pp.59-68
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• 2010

Cultural heritages are damaged by surrounding several environmental factors. Main factors are temperature, humidity, light, atmosphere and indoor pollutant, organism, etc. Therefore, to prevent damage of cultural heritage from such environmental factor, conservation environment monitoring becomes more important. Indicator is one of the simple method for environment monitoring. It can be used without expensive and complex equipments. However, it should be performed scientific examination for application to cultural heritage. In this study, some Temperature Indicators were chosen and reliability assessment was carried out for application to cultural heritage. Brightness($L^*$) is selected for reliability assessment factor. As a result of lab test, Temperature Indicators were not influenced greatly in humidity change. When they were exposed to setting temperature, the color was changed in setting temperature area and ${\pm}2^{\circ}C$ part of setting temperature. Especially brightness value was high in setting temperature area. Also, Temperature Indicators were stabilized after about 16 minutes when were exposed to temperature difference of $10^{\circ}C$ and when temperature difference with exposure environment is smaller, stabilization time shortened. Therefore, it is a possible to confirm that selected Temperature Indicator is reliable product through measurement of color difference value and naked eye observation.

• 조명전기설비학회논문지
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• 제20권2호
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• pp.29-37
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• 2006

중화학 공업은 전해조를 포함한 비선형 부하를 가지고 있다. AC-DC 컨버터가 화학공장의 전해조에 널리 쓰이고 있고, 전해조는 DC에 연결된 구조이다. 컨버터는 고조파 전류를 발생시키고, 전력계통의 전압을 왜곡시킨다. 본 논문에서는 전해조 부하의 고조파 현장 측정과 국제 고조파 관리 기준인 IEC 61000-3-6과 IEEE 519-1992에 의한 고조파 평가를 심도있게 분석한다.

• 조명전기설비학회논문지
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• 제20권6호
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• pp.35-42
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• 2006

규모가 큰 제철소는 전기로를 포함한 비선형 부하를 가지고 있다. 이들 비선형 부하는 고조파 전류를 발생 시키고, 전력 계통의 전압을 왜곡시킨다. 본 논문에서는 전기로 부하의 고조파 현장 측정, 고조파 저감을 위해 수용가 모선에 동조 필터 적용과 국제 고조파 관리 기준인 IEC 61000-3-6과 IEEE Std. 519에 의한 고조파 평가를 심도 있게 분석한다. 고조파 해석 프로그램인 EDSA는 사례연구에 시뮬레이션 도구로 사용되었다.

• Industrial Engineering and Management Systems
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• 제11권1호
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• pp.54-69
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• 2012

Chan and Qi (SCM 8/3 (2003) 209) developed an innovative measurement method that aggregates performance measures in a supply chain into an overall performance index. The method is useful and makes a significant contribution to supply chain management. Nevertheless, it can be cumbersome in computation due to its highly complex algorithmic fuzzy model. In aggregating the performance information, weights used by Chan and Qi-which aim to address the imprecision of human judgments-are incompatible with weights in additive models. Furthermore, the default assumption of linearity of its scoring procedure could lead to an inaccurate assessment of the overall performance. This paper addresses these limitations by developing an alternative measurement that takes care of the above. This research integrates three different approaches to multiple criteria decision analysis (MCDA)-the multiattribute value theory (MAVT), the swing weighting method and the eigenvector procedure-to develop a comprehensive assessment of supply chain performance. One case study is presented to demonstrate the measurement of the proposed method. The performance model used in the case study relies on the Supply Chain Operations Reference (SCOR) model level 1. With this measurement method, supply chain managers can easily benchmark the performance of the whole system, and then analyze the effectiveness and efficiency of the supply chain.

• Smart Structures and Systems
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• 제31권4호
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• pp.393-407
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• 2023

To assess structural condition in a non-destructive manner, computer vision-based structural health monitoring (SHM) has become a focus. Compared to traditional contact-type sensors, the advantages of computer vision-based measurement systems include lower installation costs and broader measurement areas. In this study, we propose a novel computer vision-based vibration measurement and coarse-to-fine damage assessment method for truss bridges. First, a deep learning model FairMOT is introduced to track the regions of interest (ROIs) that include joints to enhance the automation performance compared with traditional target tracking algorithms. To calculate the displacement of the tracked ROIs accurately, a normalized cross-correlation method is adopted to fine-tune the offset, while the Harris corner matching is utilized to correct the vibration displacement errors caused by the non-parallel between the truss plane and the image plane. Then, based on the advantages of the stochastic damage locating vector (SDLV) and Bayesian inference-based stochastic model updating (BI-SMU), they are combined to achieve the coarse-to-fine localization of the truss bridge's damaged elements. Finally, the severity quantification of the damaged components is performed by the BI-SMU. The experiment results show that the proposed method can accurately recognize the vibration displacement and evaluate the structural damage.

• 한국산업보건학회지
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• 제1권2호
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• pp.154-163
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• 1991

Particulate matter exposure leva1 of welders and grinding workers was evaluated in Banwol and Changwon industry complexes. Full period single sample and full period consecutive samples were collected with personal air samplers attached to workers. Compliance difference with 8-hour time weighted average (TWA) was compared by Korean strategy and the classification system recommended by OHSA for employee exposure to particulates. And difference of compliance was compared according to precision of measurement and analysis (total precision). Compliance rate was depended on the total precision, therefore, quality control of measurement and analysis was important.

• 조명전기설비학회논문지
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• 제26권1호
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• pp.38-43
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• 2012

For safe and stable operations of power plants, it is essential to monitor closely crucial measurement values related to power plant trips. In this paper, an intelligent power plant operating state monitoring technique enabling the operating crew member to monitor conveniently the status of the important measurement values and to perceive almost instantly the significance of the implications of those measurement values is developed. The proposed technique is called a "POST(Plant Operating State Tracking) Chart" technique and provides the foundations in developing an intelligent and integrated power plant operating state monitoring support system called the "P-OASIS"(Plant Operation Assessment and Support Intelligent System). The P-OASIS is applied to a thermal power plant of 500[MW] capacity and exhibited impressive performances.

• Journal of Advanced Marine Engineering and Technology
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• 제33권8호
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• pp.1152-1161
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• 2009

신조선 선박에서 시운전 중 주 추진 시스템의 동력을 측정하는 방법은 스트레인 게이지를 이용하여 축의 변형률로부터 얻어지는 직접적인 방법과 기계적인 또는 전기적인 픽업을 이용하여 계측한 실린더연소압력으로부터 환산된 면적에 의한 간접적인 방법으로 구분할 수 있다. 이러한 동력은 장주기로 선박의 여러 가지 해상 운동에 의해서 그리고 단주기로는 축계의 비틀림, 축계 배치 및 횡진동의 영향에 의해서 변동한다. 본 논문에서는 축동력측정과 평가를 위하여 통계적인 해석법을 소개하고 있고, 저속2행정디젤엔진과 감속기를 포함 중속 4행정 디젤엔진 모델에 의해서 이들이 확인되고 있다.