• Earthquakes and Structures
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• v.9 no.4
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• pp.851-873
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• 2015

A methodology for estimation of statistical properties (viz. mean and standard deviation) of the expected seismic damage to reinforced concrete framed structures subject to corrosion of reinforcement, over a specified reference time (typically the service life of the structure) is proposed in this paper. The damage to the structure under the earthquake loading is characterised by the damage index, determined using the modified Park and Ang damage model. The reduction in area, yield strength and strain at ultimate of steel reinforcement, and the reduction in compressive strength of cover concrete due to corrosion are taken into account in the estimation of damage. The proposed methodology is illustrated through an example problem. From the results obtained, it is noted that there is an increase of about 70% in the mean value of expected seismic damage to the reinforced concrete frame considered over a reference time of 30 years when effect of corrosion is taken into consideration. This indicates that there is a need to consider the effect of corrosion of reinforcement on the estimation of expected seismic damage.

• Proceedings of the Korean Society of Computer Information Conference
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• 2010.07a
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• pp.277-280
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• 2010

본 논문에서는 Jini 2.x 표준 보안 모델을 활용하여 모바일 기기의 신뢰성 있는 푸시 서비스 방안을 제안한다. Jini 시스템은 유비쿼터스 네트워크 환경에서 서버와 클라이언트를 연결하는 기술이다. 또한 안전한 시스템 구성을 위해서 Jini 2.x 표준 보안 모델을 마련하여 보안을 강화하였다. 푸시 서비스는 사용자가 서버에 서비스를 등록하면 서버에서 각 사용자의 모바일 기기에 데이터를 전송한다. 이 푸시 서비스는 앞으로 많은 비즈니스 모델을 만들 것으로 예상된다. 하지만 푸시 방식은 풀 방식에 비해 많은 보안 문제를 발생시킬 것이다. 본 논문에서는 이전의 신뢰성 있는 푸시 서비스를 위한 방안과 Jini 2.x 표준 보안 모델이 어떻게 안전한 푸시 서비스를 제공할 수 있는지 살펴본다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.2
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• pp.41-45
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• 2006

To get accurate positions of GPS antennas, one should apply phase center variations (PCV) corrections in the data processing. Until recently, relative calibrations, originally proposed by National Geodetic Survey of United States, were the international standard. However, in late 2006, International GNSS Service will switch to absolute calibration methods. In this study, we compared the position differences caused by different PCV models, and their effects on the calculations of Precipitable Water Vapor (PWV) in the atmosphere. Data from ${\sim}40$ permanent GPS stations in Korea were processed and we found that the vertical position differences reach up to 5 cm, depending on the model selected. Also the PWV values varied quite significantly: the maximum bias in the computed PWV values was ${\sim}4$ mm.

• Proceedings of the Korean Information Science Society Conference
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• 2004.04b
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• pp.49-51
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• 2004

XML은 인터넷 기반의 다양한 분야에서 활용될 뿐만 아니라. XML을 매개로 하여 플랫폼에 영향을 받지 않고 저장 및 관리하는 시스템을 구축하기 위하여 노력을 하고 있다. 이는 이질적인 데이터베이스나 응용체계간의 데이터 공유를 가능하게 하고 더 나아가 비즈니스 로직까지 공유를 가능케 한다. 본 논문의 목적은 기존의 국방 정보체계에서 사용되고 있는 데이터 공유방식을 향상시킨 XML기반의 웹 서비스 표준을 적용한 데이터 전송 서비스 모델을 제안하는 것이다. 데이터 전송 서비스 모델은 관련 정보체계들간의 스키마 정보를 기본으로 하여 전송 서비스 정의를 생성하고 이를 Standard Description Registry에 등록하여 보관하고 데이터 전송 요구가 발생 시 데이터 전송 서비스 정의를 사용하여 송신 체계의 데이터베이스에서 XML형식으로 데이터를 추출하고 수신체계의 데이터베이스로 전송하여 로딩하는 구조이다.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2018.06a
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• pp.305-308
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• 2018

최근 국내 지상파 UHD 방송이 시작됨에 따라 시청 중에 방송망과 브로드밴드 망을 통해 IBB 실시간 부가 서비스를 제공 받을 수 있게 되었다. 이에 따라 사업자는 IBB 서비스 표준 중 컴패니언 스크린 서비스 표준에 따라 지상파 UHD 방송 시청자들이 방송 수신기의 컴패니언 디바이스를 사용하여 연관 콘텐츠를 수신할 수 있는 기능을 제공해야 한다. 이에 본 논문에서는 IBB 부가서비스 중 생방송 이어보기 서비스를 컴패니언 디바이스를 통해 제공할 수 있는 시나리오 및 모델을 제시한다. 본 논문의 서비스 모델은 ATSC 3.0 과 HbbTV 2.0 표준의 방송 환경 시스템에서 동작함을 상정한다. 오픈소스 소프트웨어를 사용하여 해당 시스템의 설계 및 구현하여 서비스 동작을 보인다.

• Wind and Structures
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• v.32 no.5
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• pp.501-508
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• 2021

The turbine industry demands a reliable design with affordable cost. As technological advances begin to support turbines of huge sizes, and the increasing importance of wind turbines from day to day make design safety conditions more important. Wind turbines are exposed to environmental conditions that can affect their installation, durability, and operation. International Electrotechnical Commission (IEC) 61400-1 design load cases consist of analyses involving wind turbine operating conditions. This design load cases (DLC) is important for determining fatigue loads (i.e., forces and moments) that occur as a result of expected conditions throughout the life of the machine. With the help of FAST (Fatigue, Aerodynamics, Structures, and Turbulence), an open source software, the NREL 5MW land base wind turbine model was used. IEC 61400-1 wind turbine design standard procedures assessed turbine behavior and fatigue damage to the tower base of dynamic loads in different design conditions. Real characteristic wind speed distribution and multi-directional effect specific to the site were taken into consideration. The effect of these conditions on the economic service life of the turbine has been studied.

• Journal of KIBIM
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• v.11 no.2
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• pp.17-23
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• 2021

BIM (Building Information Model/Modeling) is attracting attention not only as a unit technology, but also as a factor that can promote the transformation of the entire construction industry process. This study aims to investigate the status and cases of policy introduction and legalization of BIM in foreign countries for the advancement of their own construction industry, and to discover policy implications that can be applied to Korea. The first survey uncovered policy elements, and based on this, the second survey conducted an in-depth survey of experts in actual BIM service and research activities. Looking at each priority, BIM standardization, mandating BIM in projects, payment standard establishment, and PQ additional points were given the highest level of importance.

• Proceedings of the Korea Information Processing Society Conference
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• 2008.11a
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• pp.1123-1125
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• 2008

U-City의 U-Service 솔루션들은 주민생활의 편의증대와 삶의 질 향상이라는 목적을 가지고 꾸준한 연구와 노력으로 개발되고 있다. 본 논문은 U-City의 포탈사이트 구축시 고려해야할 컨텐츠서비스 구성내용을 제안하고, U-City의 포탈사이트 구축 시 제공할 컨텐츠서비스 항목의 정의하며, U-City에서 거주민 생활편의서비스를 위한 포탈사이트 컨텐츠의 U-서비스를 활용할 수 있을 것으로 생각한다.

• International Journal of Highway Engineering
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• v.10 no.3
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• pp.199-208
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• 2008

Prediction the performance of pavement provides proper information to an agency on decision-making process; especially evaluating the pavement performance and prioritizing the work plan. To date, there are a number of approaches to predict the future deterioration of pavements. However, there are some limitation to proper prediction of the pavement service life. In this paper, pavement performance model and pavement condition prediction model are developed in order to improve pavement condition prediction method. The prediction model of pavement condition through the regression analysis of real pavement condition is based on the probability distribution of pavement condition, which set to 5%, 15%, 25% and 50%, by condition of the pavement and traffic volume. The pavement prediction model presented from the behavior of individual pavement condition which are set to 5%, 15%, 25% and 50% of probability distribution. The performance of the prediction model is evaluated from analyzing the average, standard deviation of HPCI, and the percentage of HPCI which is lower than 3.0 of comparable section. In this paper, we will suggest the more rational method to determine the future pavement conditions, including the probabilistic duration and deterministic modeling methods regarding the impact of traffic volume, age, and the type of the pavement.

• Journal of Korean Society for Quality Management
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• v.44 no.2
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• pp.389-408
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• 2016

Purpose: This study was designed to analyze the behavioral change of knowledge structures and the trends of research topics in the quality management field. Methods: The network structure and knowledge structure of the words were visualized in map form using co-word analysis, cluster analysis and strategic diagram. Results: Summarizing the research results obtained in this study are as follows. First, the word network derived from co-occurrence matrix had 106 nodes and 5,314 links and its density was analyzed to 0.95. Average betweenness centrality of word network was 2.37. In addition, average closeness centrality and average eigenvector centrality of word network were 0.01. Second, by applying optimal criteria of cluster decision and K-means algorithm to word co-occurrence matrix, 106 words were grouped into seven clusters such as standard & efficiency, product design, reliability, control chart, quality model, 6 sigma, and service quality. Conclusion: According to the results of strategic diagram analysis over time, the traditional research topics of quality management field related to reliability, 6 sigma, control chart topics in the third quadrant were revealed to be declined for their study importance. Research topics related to product design and customer satisfaction were found to be an important research topic over analysis periods. Research topic related to management innovation was emerging state and the scope of research topics related to process model was extended to research topics with system performance. Research topic related to service quality located in the first quadrant was analyzed as the key research topic.