• Composites Research
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• v.14 no.1
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• pp.47-56
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• 2001

In order to enhance high speed stability the composite air spindle system composed of a high modulus carbon fiber composite shaft, powder contained epoxy composite squirrel cage rotor and aluminum tool holder was designed and manufactured. For the optimal design of the composite air spindle system, the stacking sequence and thickness of the composite shaft were selected by considering the fundamental natural frequency and deformation of the system. The analysis gave results that the composite air spindle system had 36% higher natural frequency relative to a conventional air spindle system. The dynamic characteristics of the composite spindle system were compared with those of a conventional steel air spindle system. From the calculated and test results, it was concluded that the composite shaft and the power contained composite rotor were able to enhance the dynamic characteristics of the spindle system effectively due to the low inertia and high speific stiffness of the composite materials.

• Composites Research
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• v.12 no.6
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• pp.43-52
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• 1999

This paper explains the development of a concurrent engineering system for the rlesign of composite structures. The concurrent engineering system is developed to meet the demand for the better quality products with lower production cost and time. In this study, to compose the architecture of concurrent engineering system, the commercial and noncommercial programs related to design and analysis of composite structures are surveyed and classified. The concurrent engineering system is including various design modules such as design/analysis of composite structures using CLPT and FEM, buckling and post bucking analysis, thermo-elastic analysis of carbon-carbon composite, and optimum design using expert system and genetic algorithm. For the integration and management of softwares, the concurrent engineering system is realized by Microsoft visual $C++{^\circledR}$ that provide multi-tasking and graphic user interface environment.

• Proceedings of the Korea Information Processing Society Conference
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• 2000.10b
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• pp.1309-1312
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• 2000

컴포넌트를 기반으로 하는 소프트웨어 개발 방법론은 시스템의 규모가 크고 구성이 복잡한 지리정보 시스템에 효율적으로 적응될 수 있다. 이것은 특히 개방형 GIS를 위한 설계와 구현 방법에도 이용되고 있다. 본 논문에서는 복합 피쳐를 지원하는 3차원 지리정보시스템의 컴포넌트 기반 설계 사례에 대해 설명한다. 본 논문에서 제안한 시스템은 OpenGIS 규격과의 호환성을 고려하고 복합 피쳐 및 복합 지리요소를 지원하며 객체 지향 분석 설계 방법론을 이용하여 설계되었다. 본 시스템은 3차원 지리요소의 모델링, 가시화, 공간분석 기능과 4차원 공간 데이터에 대한 질의 기능을 포함하고 있다. 향 후 복잡한 도심 건물 지역을 대상으로 층별 시공간 관리 분석 시스템 등으로 응용될 전망이다.

• Aerospace Engineering and Technology
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• v.2 no.2
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• pp.33-44
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• 2003

This paper describes the design and analysis technology of composite flexure and composite paddle-type blade which are all key technologies on hingeless rotor system. Through replacing the existing metal or engineering plastic flexure part with composite part, Several required structural analysis were accomplished, which are static analysis by using NASTRAN and dynamic analysis by using FLIGHTLAB. The dynamic characteristics of composite hingeless hub attached with paddle-type blade was also investigated. Further more, small-scaled paddle-type blade was designed using froude scaled properties of existing full size blade. Through this design procedure of composite paddle-type blade, the structural design method was achieved. These results will be applied to accomplishing current project named as "the development of next-generation helicopter rotor system."

• Journal of Intelligence and Information Systems
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• v.10 no.2
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• pp.39-51
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• 2004

Product factory is a real-time financial product design system for the Internet customers. The hybrid product is a product taking combined characteristics of two different products. Hybrid product factory is a product factory that designs hybrid products from two different products based on both business rules and customer requirements. Though the importance of product factory is emphasized in the industry, there has not been much research peformed regarding product factory. In this research, we developed a product factory system that designs hybrid products. To design a hybrid product, it is necessary to have a method to combine attributes and values of two different products, and a method to control the combining operations to properly reflect business requirements. In this research, we developed low different combining operators and business rule representations. rn addition, to prove the effectiveness of this methods, we implemented a prototypical system and demonstrated on cases regarding financial loan products.

• Journal of Energy Engineering
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• v.8 no.1
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• pp.159-165
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• 1999

복합화력 발전플랜트의 운전에서 특히 하절기의 첨두부하시에 외기온도의 상승으로 인한 가스터빈의 출력 감소를 해결하기 위한 방법으로 LNG 연료가 보유하고 있는 냉열을 이용하여 압축기로 유입되는 공기 온도를 감소시키는 냉각시스템의 개념을 개발하고자 복합화력 발전플랜트에 대한 설계점 및 외기온도 변화에 대한 탈설계점 모델링 연구를 수행하였다. 대상 프랜트는 940 MW 서인천 복합 발전플랜트 모듈의 단위 블록을 선택하였으며 발전플랜트 전용 해석코드인 GateCycle을 이용하여 가스터빈과 증기사이클의 주요 기기 들에 대한 모델을 개발하였다. 개발된 모델의 결과를 대상플랜트의 시운전결과와 비교하여 모델의 적정성을 검증하였다. 출력, 효율, 온도 및 유량 등 주요 설계인자들이 최대 ~1.3%의 상대오차 범위 안에서 만족할 만한 신뢰도를 갖는 것을 확인하였다. 탈설계점 성능해석은 본 논문과 관련한 연구의 주목적인 LNG 냉열에 의한 유입공기 냉각시스템 설계시의 경계변수인 외기온도 증가에 대한 각 사이클의 특성변화를 대상으로 하였다. 종합적으로 외기온도가 증가하면 압축기로 유입되는 공기의 양과 이에 대응하는 소요 연료량이 동시에 감소하므로 연소에 따른 가스터빈의 팽창비가 감소한다. 이로 인하여 외기온도 증가시에 가스터빈 출력감소율은 0.5%/$^{\circ}C$로서 배기가스를 이용하는 증기사이클의 출력감소율 0.2%/$^{\circ}C$에 비해 민감하므로 가스터빈 유입공기의 냉각시스템의 설계는 복합화력발전 플랜트의 효율 향상에 크게 기여할 것으로 예상된다.

• Proceedings of the Korean Information Science Society Conference
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• 2003.04c
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• pp.609-611
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• 2003

현재 건축 설계 분야에 사용되고 있는 시스템들은 대부분 데스크탑을 기반으로 하고 있고 설계시에 건축물을 입면, 측면, 평면 등으로 분리하는 인터페이스를 제공하고 있다. 그렇기 때문에 현재 설계되고 있는 건축물이 실제 거리에 적용되었을 때의 느낌을 제대로 파악하기 어렵다. 이에 대해, 실재감을 중시한 가상현실을 통한 건축 응용들이 있었으나 3차원에서의 상호작용이 쉽지 않기 때문에 가능한 상호작용이 제한되는 경향이 있었다. 이러한 한계를 극복하기 위해 본 논문에서는 실감 있는 3차원 입체 경관을 보여주면서, 설계에 필요한 상호작용의 특성에 따라 2차원과 3차원의 인터페이스 미디어를 복합 활용하는 이른바 복합 인터페이스를 활용한 거리경관 디자인 시스템을 제시한다. 이 시스템을 사용함으로써 사용자들은 실재감 있는 경관을 몰입형 벽면 디스플레이를 통해 확인하면서 모바일 기기를 활용한 복합 인터페이스를 통해 설계할 수 있게 된다.

• Journal of the Korean Society for Marine Environment & Energy
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• v.19 no.3
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• pp.194-202
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• 2016

This study aims to review a topology optimization based on finite element analysis (FEA) for conceptual design of platform in the 10MW class floating type wave-wind hybrid power generation system (WHPGS). Two topology optimization theories, density method (DM) and homogenization design method (HDM) were used to check which one is more effective for a simplified structural design problem prior to the topology optimization of platform of WHPGS. From the results of the simplified design problem, the HDM was applied to the topology optimization of platform of WHPGS. For the conceptual platform design of WHPGS, FEA model was created and then the structural analysis was performed considering offshore environmental loads at installation site. Hydrodynamics analysis was carried out to calculate pressure on platform and tension forces in mooring lines induced from the offshore environmental loads such as design wave and current. Loading conditions for the structural analysis included the analysis results from the hydrodynamic analysis and the weights of WHPGS. Boundary condition was realized using inertia relief method. The topology optimization of WHPGS platform was performed using the HDM, and then the conceptual arrangement of main structural members was suggested. From the results, it was confirmed that the topology optimization might be a useful tool to design the conceptual arrangement of main structural members for a newly developed offshore structure such as the floating type WHPGS.

• Journal of Aerospace System Engineering
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• v.11 no.4
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• pp.30-35
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• 2017

In this work, a manufacturing and structural test of 1kW class horizontal axis wind turbine blade using natural-fiber composite was performed. The aerodynamic design of blade was performed after investigation on design requirement. The structural design load was investigated after aerodynamic design of blade. And also, structural design of blade was carried out. The structural design of blade was carried out using the simplified methods such as the netting rule and the rule of mixture applied to composite. The structural safety of the designed blade structure is investigated through the various load cases, stress, deformation and buckling analyses using the FEM method. Finally, the blade manufacturing and structural test using natural composite was carried out.

• Journal of the military operations research society of Korea
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• v.36 no.3
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• pp.57-68
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• 2010

This Study proposes that a SoS(System of Systems) Conceptual Design Model which is developed for the SoS establishment, requirement and decision, utilizing SoS engineering and architecture methodology, and the Model performed with the Process Transition Map using subject matter expert survey. Establishing an Integrated Battle Experimentation System(IBES) for the future force development, the process product of IBES was conceptually designed using a SoS Conceptual Design Model.