• KSII Transactions on Internet and Information Systems (TIIS)
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• 제14권3호
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• pp.1043-1064
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• 2020

A kind of Subjective Imaging Effect Assessment (SIEA) method and its applications on intelligent imaging terminal design in engineering site are presented. First, some visual assessment indices are used to characterize the imaging effect: the image brightness, the image brightness uniformity, the color image contrast, the image edge blur, the image color difference, the image saturation, the image noise, and the integrated imaging effect index. A linear weighted function is employed to carry out the SIEA computation and the Analytic Hierarchy Process (AHP) technique is used to estimate its weights. Second, a SIEA software is developed. It can play images after the settings of assessment index or assessment reaction time, etc. Third, two cases are used to illustrate the application effects of proposed method: the image enhancement system design for surveillance camera and the imaging environment perception system design for intelligent lighting terminal. A Prior Sequential Stimulus (PSS) experiment is proposed to improve the evaluation stability of SIEA method. Many experiment results have shown the proposed method can realize a stable system design or parameters setting for the intelligent imaging terminal in engineering site.

• 한국공간구조학회논문집
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• 제23권3호
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• pp.57-69
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• 2023

In this study, in order to establish a strategy for developing an fire following earthquake risk assessment method that can utilize domestic public databases(building datas, etc.), the method of calculating the ignition and fire-spread among the fire following earthquake risk assessment methodologies proposed by past researchers is investigated After investigating and analyzing the methodology used in the HAZUS-MH earthquake model in the United States and the fire following earthquake risk assessment methodology in Japan, based on this, a database such as a domestic building data utilized to an fire following earthquake risk assessment method suitable for domestic circumstances (planned) was suggested.

• 대한조선학회논문집
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• 제30권2호
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• pp.161-176
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• 1993

본 논문에서는 주어진 상황에 맞추어 적절한 수준에서 건전성평가를 수행하기 위하여, 개정된 BSI PD 6493의 3단계 평가방법에 균열성장효과를 고려한 건전성 평가방법과 균열의 안정성장을 엄밀히 고려할 수 있는 안정성 평가방법(stability assessment method:SAM)과 더불어 소성 붕괴를 평가하는 극한하중해석을 고려한 건전성 평가방법을 정식화하였다. 또한 신뢰성이론 중 2차 모멘트방법을 사용하여, center cracked panel(CCP) 시편과 관통균열을 갖는 파이프에 대하여, 신뢰성해석에 의한 건전성 평가를 수행하였다. 신뢰성해석을 수행하는데 필요한 확률변수들의 통계적 특성은 지금까지 보고된 그들 변수들의 실험자료와 통계해석의 결과들을 이용하였다. 또 기존의 신뢰성해석에서 정확한 파괴확률을 구할 수 있는 Monte Carlo 방법을 사용하여, 본 논문의 유용성을 검토하였다.

• 공학기술논문지
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• 제6권2호
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• pp.121-124
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• 2013

This paper proposed a new concept of estimating method for LED(light-emitting diode) delamination with high accuracy. Usually, The LED is composed several materials which are LED chips, gold wire, phosphor, epoxy resin, adhesive, reflector and lead frame. These different materials are usually delaminated in a trouble conditions which are huge temperature difference, hot and humid or mechanical shocked. When the components are delaminated, a luminance will be lost, moisture be absorbed easily and a thermal resistance be increased attendantly. As a conventional method to estimate a delamination of LEDs, a solution immersing method is usually used in a field of LED manufacturing companies or researching institutes. This method has an advantage of simplicity but it is only shown that the existence of delamination or not. In this paper, we have proposed an estimating method for LEDs delamination using the polishing and the electron microscope. New proposed method has shown the result of confirming delamination without destruction and enabled quantitative analysis for LED delamination.

• 대한수학교육학회지:수학교육학연구
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• 제8권1호
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• pp.217-235
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• 1998

The purpose of this study is to define the altenative assessment and to suggest the method of scoring system. Alternative assessment includes any type of assessment in which student create reponses to a question rather than choosing a responses form given list( as for multiple choice, true/false, or matching). Alternative assessment can includes short answer questions, essay, performances, oral presentation, demonstrations, exhibitions, portfolios, and etc. To evaluate the each type of assessment, we can apply the method of holistic scoring and analytic scoring system. Also we have to concern the type of scoring mechanism directly relate to what we want to assess, our purpose for assessment fitting into the educational enterprise. Before applying the alternative assessment in our classroom, we need to step back and reconsider all our design features and teachers' responsibility.

• 대한전자공학회논문지SP
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• 제47권5호
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• pp.56-61
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• 2010

본 논문에서는 이어폰의 주관 평가 기법에 대해서 소개한다. 음질의 주관 평가는 동시비교를 위한 평가 자극간의 즉각적인 스위칭을 제공하도록 설계되어야 한다. 그럼에도 불구하고 이어폰의 음질 평가의 경우에 있어서는, 물리적으로 평가 자극간의 즉각적인 스위칭이 불가능하여 직접적인 주관 평가에 어려운 점이 있다. 이에, 본 논문에서는 각 이어폰으로부터의 자극을 녹음하여 녹음된 자극간의 동시 비교를 통하여 이어폰을 평가하는 방법을 제안하고, 이에 필요한 선처리들과 평가 결과에 대하여 소개한다.

• Journal of Information Technology Applications and Management
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• 제25권2호
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• pp.41-52
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• 2018

This paper presents a method for accurate camera self-calibration based on SIFT Feature Detection and image quality assessment. We performed image quality assessment to select high quality images for the camera self-calibration process. We defined high quality images as those that contain little or no blur, and have maximum contrast among images captured within a short period. The image quality assessment includes blur detection and contrast assessment. Blur detection is based on the statistical analysis of energy and standard deviation of high frequency components of the images using Discrete Cosine Transform. Contrast assessment is based on contrast measurement and selection of the high contrast images among some images captured in a short period. Experimental results show little or no distortion in the perspective view of the images. Thus, the suggested method achieves camera self-calibration accuracy of approximately 93%.

• Nuclear Engineering and Technology
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• 제50권8호
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• pp.1210-1216
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• 2018

Site or multi-unit (MU) risk assessment has been a major issue in the field of nuclear safety study since the Fukushima accident in 2011. There have been few methods or experiences for MU risk assessment because the Fukushima accident was the first real MU accident and before the accident, there was little expectation of the possibility that an MU accident will occur. In addition to the lack of experience of MU risk assessment, since an MU nuclear power plant site is usually very complex to analyze as a whole, it was considered that a systematic method such as probabilistic safety assessment (PSA) is difficult to apply to MU risk assessment. This paper proposes a new MU risk assessment methodology by using the conventional PSA methodology which is widely used in nuclear power plant risk assessment. The logical failure structure of a site with multiple units is suggested from the definition of site risk, and a decomposition method is applied to identify specific MU failure scenarios.

• 한국환경보건학회지
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• 제38권1호
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• pp.66-72
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• 2012

Objectives: The AHERA method by the US EPA, ASTM E2356-04, and HSG264 by the UK HSE, all of which are hazard/risk assessment methods for asbestos-containing building materials, were reviewed and compared based on 231 homogeneous areas. In addition, the current Act on Asbestos Safety Management (enforcement: April 29, 2012) was reviewed and analyzed. This trial provided fundamental data for improving the current asbestos hazard/risk assessment method. Methods: For the hazard/risk assessment of 77 asbestos-containing public buildings including schools, 231 homogeneous areas were selected, each of which was assessed using AHERA, ASTM E2356-04, and HSG264. Results: The matching rate of the hazard/risk assessment stood at 20.4 percent between AHERA and ASTM, at 71.4 percent between AHERA and HSG264 and at 17.8 percent between ASTM and HSG264. The AHERA method includes a seven-category rating scale. There were three categories, two of which have three subcategories. ASTM provides two decision-making charts consisting of ten rating scales for current condition estimation and for potential for disturbance estimation. In addition, the HSG264 method has a total of 20 scores with four items, and then provides four grades. This HSG264 method cannot clearly separate current condition and potential for disturbance. Conclusions: In the Korean Act on Asbestos Safety Management, the hazard/risk assessment method for asbestos-containing building materials should consider balance between current condition estimation and the potential for disturbance estimation.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2006년도 추계학술대회 논문집
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• pp.1132-1139
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• 2006

Railway risk is evaluated by a method of linking event trees and fault trees as the general PSA(Probabilistic Safety Assessment) model for the risk assessment of complex systems. Accident scenarios causing undesirable events are modeled by event trees comprised of several accident sequences. Each branch located in the accident progression of the event tree is modeled by an fault tree or can be represented by some value too simply. We usually evaluate the frequency of the whole sequence by adding them after calculating the frequency of each sequence at a time. However, since there are quite a number of event trees and fault trees in the railway risk assessment model, the number of sequence to evaluate increases and preparation for the risk assessment costs much time all the more. Also, it may induce errors when analysts perform the work of quantification. Therefore, the systematic maintenance and control of event trees and fault trees will be essential for the railway risk assessment. In this paper we introduce an integrated assessment method using one-top model and develop a risk assessment tool for the maintenance and control of the railway risk model.