• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2004년도 ICEIC The International Conference on Electronics Informations and Communications
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• pp.87-91
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• 2004

This research presents distributed database and knowledge-base modeling approach for intelligent product design system. The product design information in this study is described by a collection of rules and design knowledge that are utilized according to the product development procedures. In this work, a network-based architecture has been developed to enable dispersed designers to simultaneously accomplish remote design tasks. A client/server communication diagram has also been proposed to facilitate consistent primary information modeling for multi-user access and reuse of designed results. An intelligent product design system has been studied with the concepts of distributed database and network-based architecture in order to support concurrent engineering design and automatic design part assembly. The system provides the capability of composing new designs from proper design elements stored in the database and knowledge-base. The distributed intelligent product design is applied to the design of an automobile part as an example.

• 한국CDE학회논문집
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• 제15권6호
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• pp.467-475
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• 2010

Due to the needs of design optimization and productivity for modernized Korean traditional house, standardization of Korean traditional building components is proceeding by BIM (Building Information Modeling). Currently, most of BIM software support object-based parametric modeling. By means of parameterized Korean traditional building components, the shape and assembly relation can be controlled. Although IFC(ISO/PAS 16739), which is an international standard in the AEC field, has been developed for information exchange among BIM software, IFC and other existing common data formats cannot be exchangeable parametric information. For the exchangeable parametric information within IFC, the authors defined meta-data by using Pset(Property-Set). The authors analyzed results about interoperability test in Revit $Architecture^{TM}$, $ArchiCAD^{TM}$ and Digital $Project^{TM}$. In order to solve found problems, the authors developed a translator to improve interoperability among BIM software.

• Structural Engineering and Mechanics
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• 제70권4호
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• pp.421-429
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• 2019

This paper presents an analytical model for the estimation of initial lateral stiffness of steel moment resisting frames with masonry infills. However, rather than focusing on the single bay-single storey substructure, the developed model attempts to estimate the global stiffness of multi-storey and multi-bay frames, using an assembly of equivalent springs and taking into account the shape of the lateral loading pattern. The contribution from each infilled frame panel is included as an individual spring, whose properties are determined on the basis of established diagonal strut macro-modeling approaches from the literature. The proposed model is evaluated parametrically against numerical results from frame analyses, with varying number of frame stories, infill openings, masonry thickness and modulus of elasticity. The performance of the model is evaluated and found quite satisfactory.

• 화약ㆍ발파
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• 제23권3호
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• pp.27-42
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• 2005

본 연구에서는 $PFC^{3D}$상에서 공내입자들의 반경을 팽창/수축시키는 기법을 통해 공벽입자들에 접촉력의 형태로 폭발압력을 부여하는 폭원모델링을 기법을 소개하고, 제안된 기법을 이용하여 홉킨슨 효과 효과와 스폴링 현상을 응용하여 암석코어에 대한 응력파의 전파 및 반사과정을 기존의 외력을 적용함으로써 서로 비교하여 보았다. 암석코어는 직경 20m, 길이 200mm의 입자결합체로서 접촉결합을 이용하여 구성하였으며, 시료의 선단에 주기 0.050m$(50{\mu}s)$의 펄스형태의 폭발하중을 기존의 방법과 제안된 폭원모델링 기법을 이용하여 각기 입사시켰다. 해석결과 두 기법은 서로 유사한 결과를 보였으며, 입사압축파는 0.060ms$(60{\mu}s)$ 이후 시료의 후단에서 반사되어 반사인장파의 형태로 되돌아오면서 시료의 축방향과 직각방향으로 인장균열을 발생시켰다. 또한 시료 중을 전파하는 응력파의 속도는 4,167m/s로 계산되어 물리시료에 대한 측정치 4,300m/s와 $3\%$ 정도의 근소한 오차를 보였다.

• Journal of Microbiology and Biotechnology
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• 제18권6호
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• pp.1070-1075
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• 2008

IscA was proposed to be involved in the iron-sulfur cluster assembly encoded by the iscSUA operon, but the role of IscA in the iron-sulfur cluster assembly still remains controversial. In our previous study, the IscA from A. ferrooxidans was successfully expressed in Escherichia coli, and purified to be a [$Fe_4S_4$] -cluster-containing protein. Cys35, Cys99, and Cys101 were important residues in ligating with the [$Fe_4S_4$] cluster. In this study, Asp97 was found to be another ligand for the iron-sulfur cluster binding according to site-directed mutagenesis results. Molecular modeling for the IscA also showed that Asp97 was a strong ligand with the [$Fe_4S_4$] cluster, which was in good agreement with the experimental results. Thus, the [$Fe_4S_4$] cluster in IscA from A. ferrooxidans was ligated by three cysteine residues and one aspartic acid.

• 한국항공우주학회지
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• 제37권9호
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• pp.837-842
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• 2009

구성 모드(Component mode) 합성법을 이용하여, 태양전지판의 유연구조 진동특성을 고려한 위성의 축약된 동적 모델링 기법을 수립하였다. 유연구조 위성의 본체와 태양전지판을 서로 다른 두 개의 부구조물로 나누고, 각각의 국부좌표계에 대하여 유도된 부구조물 표현식들을 위성 전체의 기준좌표계에 대해서 합성하였다. 수립된 부구조물 합성법은 단일 태양전지판을 갖는 유연구조 위성의 수치적 예제에 적용되었으며, 태양전지판의 회전을 고려한 전달함수 결과의 고찰을 통하여 동적 모델링 기법의 타당성을 확인하였다.

• 한국BIM학회 논문집
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• 제5권1호
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• pp.1-7
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• 2015

Modular technology has become a major issue of the construction industries to enhance their productivity. Modular bridge construction generally requires the data exchange between the contractors, designers, fabricators and constructors. Therefore, a readily accessible information model interface module based on BIM technology is essential for their communication during a project life-cycle. In this study, BIM based information model interface module for a modular pier was developed. For the information models, the PBS(Product Breakdown Structure) and LOD(Level of Development) were defined. Next, all components of a modular pier were conducted by the parametric modeling technique, and then 3D cell library interface was developed. An nterface module was also developed using VBA(Visua basic Application) for exchanging a data from 3D model library to other softwares such as Microstation, AutoCad and Excel and was connected with MS Access database. The developed information model interface module would improve the design quality of the modular pier and reduce the time and cost for design. Updated 3D information models could be utilized for the fabrication, assembly, and construction process for modular piers.

• 대한조선학회논문집
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• 제50권5호
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• pp.314-323
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• 2013

Production simulation technology is beneficial to solve the complicated and fluctuated problems in a shipyard. It takes too much time and effort to build simulation models in the field, though. This research proposes a feasible method to reduce the difficulties related to simulation modeling for the factory or shop capacity analysis. In addition, a proposed neutral data format for production information is efficient to manage information acquisition for simulation modeling automation. A panel block shop model is contributed to comparison between the conventional technique and the automated one. The automation technique is highly recommended to run a rapid simulation in the shipyard problem.

• 디지털산업정보학회논문지
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• 제10권1호
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• pp.181-193
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• 2014

The environment of supply chains is rapidly changed to global and eco-freindly work process. However, at current environment, it is not easy to grasp work flow and to analyze energy efficiency. Improving energy efficiency and visibility for goods flow can contribute to increases in customer attitudes and reductions in overall production costs Additionally, it can lead to increases in work efficiency and reductions in overall production costs. Until recently, efforts to improve energy performance focused on manufacturing industry. Those efforts have expanded to the supply chain. In this paper, we perform business process modeling about supply chain for visibility and sustainability - information and component flows - from assembly plants to logistics. This paper defines the work and information flows by modeling the underlying logical structures of the supply chain and the business processes that determine impact of visibility and sustainability. We model processes using the modeling methodology specified by UN/CEFACT. This methodology explains business process functionality and business transactions by UML diagram. The output of this paper would be useful in grasping work flow and capturing the used energy.

• 한국정밀공학회지
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• 제13권7호
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• pp.90-99
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• 1996

In the area of assembly process of micro-chips and electronic parts on the printed circuit board, surface mounting device(SMD) is used as a fundamental tool. Generally speaking, the motion of the SMD is based on the ball screw system operated by any type of actuators. The ball screw system is a mechanical transformed which converts the mechanical rotational motion to the translational one. Also, this system could be considered as an efficient motion device against mechanical backlash and friction. Therefore a dynamic modeling and state sensitivity analysis of the ball screw system in SMD have to be done in the initial design stage. In this paper, a simple mathematical dynamic model for this system and the sensit- ivity analysis are mentioned. Especially, the bond graph approach is used for graphical modeling of the dynamic system before analysis stage. And the direct differentiation method is used for the state sensit- ivity analysis of the system. Finally, some trends for the state variables with respect to the design variables could be suggested for the better design and faster operating based on the results of dynamic and state sensitivity.