• International Journal of Naval Architecture and Ocean Engineering
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• 제11권2호
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• pp.980-992
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• 2019

This paper describes a model test and numerical simulation of a 750-kW-semi-submersible platform wind turbine under several wind and wave conditions for validation of the numerical simulation model. The semi-submersible platform was designed to support the 750-kW-wind turbine class and operate at a water depth of 50 m. The model tests were performed to estimate the performance characteristics of the wind turbine system in the wide tank of the University of Ulsan. Motions and loads of the wind turbine system under the wind and wave conditions were measured and analyzed. The NREL-FAST code was used to simulate the wind turbine system, and the results were compared with those of the test model. The results demonstrate that the numerical simulation captures noticeably the fully coupled floating wind turbine dynamic responses. Also, the model shows a good stability and small responses during waves, wind, and operation of the 750-kW-floating offshore wind turbine.

• 경영정보학연구
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• 제12권2호
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• pp.1-23
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• 2010

엔터프라이즈 정보화를 추진하는데 있어서 가장 심각한 문제 중 하나는 서로 연계 통합되지 않은 사일로(Silo) 시스템 문제이다. 정보전략계획(Information Strategy Planning)은 비즈니스에 필요한 개별시스템 기능성 도출에 국한되어 오히려 이러한 사일로 문제를 가중시키고 있다. 본 연구는 엔터프라이즈 사일로 문제가 엔터프라이즈 제반 요소들이 가지는 관계에 대한 총체적 시각, 곧 '아키텍처적 시각'이 부재하기 때문이라고 보고, 이러한 엔터프라이즈 요소간 관계를 정의하고 체계화할 수 있는 '엔터프라이즈 아키텍처 지향 모델'을 제안한다. 이를 위해 본 연구는 엔터프라이즈 제반 구성요소들 상호간에 수직적, 수평적 관계성을 부여하고 엔터프라이즈가 이들 관계에 있어서 거치는 진화의 단계를 설정한다. 엔터프라이즈 아키텍처 지향 모델에서 수직적 관계는 Kaplan과 Norton의 연구로부터 도출된 성과, 역량, 전략이라는 세 요소가 조직 상하간에 전략적 관리적 측면에서 '연계(Alignment)'되어야 함을 의미한다. 수평적 관계는 Ross 등이 통합 대상으로 다룬 정보기술, 데이터/프로세스, 비즈니스 컴포넌트 요소들이 수평 조직간에 기능적 실행적 측면에서 '통합(Integration)'되어야 함을 강조한다. 본 모델은 엔터프라이즈의 현재와 미래 아키텍처를 사상하는 개념공간으로서 엔터프라이즈의 현재 모습을 파악하고 엔터프라이즈가 지향하는 미래 모습을 도출하며 현재에서 미래로의 이행을 인도하는 개념적 틀로서 작용하게 된다. 끝으로 본 모델의 적용 사례를 들고 모델의 적용이 각 엔터프라이즈가 지향하는 엔터프라이즈 모습에 따라 어떻게 달라질 수 있는지를 논의한다.

• 대한조선학회논문집
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• 제56권1호
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• pp.82-93
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• 2019

In this paper, the ductile fracture criteria for a marine structural steel (EH36) are presented and validated. The theoretical background of the recently developed Hosford-Coulomb (HC) fracture strain model and the DSSE fracture strain model which was developed to apply to the shell elements is described. In order to accurately estimate the flow stress in the large strain range up to the fracture, the material constants for the combined Swift-Voce constitutive equation were derived by the numerical analyses of the smooth and notched specimens made from the EH36 steel. As a result of applying the Swift-Voce flow stress to the other notched specimen model, a very accurate load - displacement curve could be derived. The material constants of the HC fracture strain and DSSE fracture strain models were independently calibrated based on the numerical analyses for the smooth and notch specimen tests. The user subroutine (VUMAT of Abaqus) was developed to verify the accuracy of the combined HC-DSSE fracture strain model. An asymmetric notch specimen was used as verification model. It was confirmed that the fracture of the asymmetric specimen can be accurately predicted when a very small solid elements are used together with the HC fracture strain model. On the other hand, the combined HC-DSSE fracture strain model can predict accurately the fracture of shell element model while the shell element size effect becomes less sensitive.

• 한국데이타베이스학회:학술대회논문집
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• 한국데이타베이스학회 1999년도 춘계공동학술대회: 지식경영과 지식공학
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• pp.487-495
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• 1999

본 논문은 Zachman ＆ Soho ［8］의 확장 정보 System 체계(extended lnformation System Architecture)의 개념을 ARIS Tool을 이용하여 구현한 Case study이다. 본 논문의 특징은 전략, Process, 조직,Data, Network, Time의 6 개 Model의 연계구조와 각 Model의 계층적 관계를 인도의 대표적 기업 중 하나인 TATA 제철소 냉연 공장의 신규 생산관리 System 구축사례를 통하여 제시하였다는데 있다.

• 한국지능정보시스템학회:학술대회논문집
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• 한국지능정보시스템학회 1999년도 춘계공동학술대회-지식경영과 지식공학
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• pp.487-495
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• 1999

본 논문은 Zachman & Soho [8]의 확장 정보 System 체계(extended information System Architecture)의 개념을 ARIS Tool을 이용하여 구현한 Case Study 이다. 본 논문의 특징은 전략, Process, 조직, Data, Network, Time의 6개 Model의 연계구조와 각 Model의 계층적 관계를 인도의 대표적 기업 중 하나인 TATA 제철소 냉연 공장의 신규 생산과리 System 구축사례를 통하여 제시하였는데 있다.

• 한국정보컨버전스학회논문지
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• 제1권1호
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• pp.41-46
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• 2008

웹 기술 기반의 콘텐츠 개발 및 운영으로 다른 환경에서의 콘텐츠 활용을 토대로 교육자원의 정보들을 통합 운영할 수 있는 관리 중심체인 e-learning 시스템의 중요성과 필요성이 대두되고 있으며, 교육용 어플리케이션은 현재 표준화되지 않은 개발 프로세스를 기반하여 개발하고 있는 실정이다. 따라서, 교육 콘텐츠의 재사용을 높이기 위해 국제적 학습 표준인 SCORM(Sharable Content object Reference Model)을 기반으로 하나의 플랫폼에 있어서 시스템 개발 중 다른 플랫폼으로의 재사용이 가능한 핵심자산을 이용하여 조립, 생산할 수 있는 방안으로 체계적인 교육자원을 개발하고 지원하기 위한 교수-학습지원 시스템 개발에 초점을 둔 연구가 요구된다. 따라서, 본 논문에서는 교육적 도메인으로 접근하여 MDA(Model Driven Architecture)상의 교수-학습지원 시스템을 정의한다. 또한 학습콘텐츠 표준 메타데이터를 이용하여 콘텐츠에 관한 분석 및 설계를 하고 MDA 자동화 툴을 이용한 핵심자산을 통해 실제 교수자가 필요로하는 콘텐츠를 제공할 수 있는 교수-학습지원 시스템을 개발하고자 한다.

• 대한조선학회논문집
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• 제50권2호
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• pp.120-128
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• 2013

This paper presents the results of sloshing experiments having different fluids in model tanks with various density ratios. The experimental model consisting water and air at ambient, which has been commonly used, is not consistent in density ratio with that of an actual LNG cargo tank. Therefore, an advanced experimental scheme is developed to consider the same density ratio of LNG and NG by using a mixed gas of sulfur hexafluoride ($SF_6$) and nitrogen ($N_2$). For experimental observation, a two-dimensional model tank of 1/40 scale and a three-dimensional model tank of 1/50 scale have been manufactured and tested at various conditions. Two different fillings with various excitation frequencies under regular motions have been considered for the two-dimensional model tank, and three different filling levels under irregular motions have been imposed for the three-dimensional model tank. The density ratio between gas and liquid varies from the ratio of the ambient air and water to that of the actual LNG cargo container, and the different composition of gas is used for this variation. Based on the present experimental results, it is found that the decrease of sloshing pressure is predicted when the density ratio increases.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2008년도 정기 학술대회
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• pp.247-252
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• 2008

Systems architecture of information models for construction industry is introduced. The architecture ful fills international standards, such as ISO 10303(STEP) and IAI IFC, etc. It is defined in web service description language(WSDL) and ISO 10303-11(EXPRESS) language. A standard platform for this standard architecture is also developed. This platform has several tools which can transform EXPRESS description file into C++ or Java languages and which also can generate an IDL file or OWL file from an EXPRESS file. System architects, software engineers, information system consultants can use these standards to define their information model for construction industry in standardized way. Construction engineers can test this information model with ease using standard testing tools and testing method, which is also a part of standard architecture of information systems for virtual construction.

• Computers and Concrete
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• 제17권5호
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• pp.655-672
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• 2016

A predictive model for chloride binding isotherms of blended cements with various supplementary cementitious materials (SCMs) was established in this work. Totally 560 data points regarding the chloride binding isotherms of 106 various cements were collected from literature. The total amount of bound chloride for each mixture was expressed a combinational function of the predicted phase assemblage and binding isotherms of various hydrated phases. New quantitative expressions regarding the chloride binding isotherms of calcium-silicate-hydrate (C-S-H), AFm, and hydrotalcite phases were provided. New insights about the roles of SCMs on binding capabilities of ordinary portland cements (OPC) were discussed. The proposed model was verified using separate data from different sources and was shown to be reasonably accurate.

• 센서학회지
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• 제30권5호
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• pp.290-294
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• 2021

Experts have designed popular and successful model architectures, which, however, were not the optimal option for different scenarios. Despite the remarkable performances achieved by deep neural networks, manually designed networks for classification tasks are the backbone of object detection. One major challenge is the ImageNet pre-training of the search space representation; moreover, the searched network incurs huge computational cost. Therefore, to overcome the obstacle of the pre-training process, we introduce a network adaptation technique using a pre-trained backbone model tested on ImageNet. The adaptation method can efficiently adapt the manually designed network on ImageNet to the new object-detection task. Neural architecture search (NAS) is adopted to adapt the architecture of the network. The adaptation is conducted on the MobileNetV2 network. The proposed NAS is tested using SSDLite detector. The results demonstrate increased performance compared to existing network architecture in terms of search cost, total number of adder arithmetics (Madds), and mean Average Precision(mAP). The total computational cost of the proposed NAS is much less than that of the State Of The Art (SOTA) NAS method.