• 전기학회논문지P
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• 제63권4호
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• pp.356-360
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• 2014

The environmental pollution caused by green-house gases such as $SF_2$ has been becoming the main issue of industrial society. As a part of these efforts, 180 countries signed the Kyoto Protocol in 1997 to cut back on their green-house gas emissions [1]. Therefore, a study on the dielectric characteristics of the $GN_2$ is important for designing a eco-friendly high voltage apparatuses. In this paper, to develop an electrically reliable, stable, and eco-friendly high voltage apparatus, the breakdown voltage and partial discharge inception voltage characteristics in $GN_2$ considering utilization factors are studied for the establishment of insulation design criteria of an high voltage apparatus. Dielectric experiments are performed by using several kinds of sphere-plane electrode systems made of stainless steel. Also, the dielectric characteristics of the $GN_2$ are analyzed by using a Finite Elements Method (FEM) according to various field utilization factors. The results are expected to be applicable to designing the high voltage apparatuses using $GN_2$ as an insulation gas.

• 토지주택연구
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• 제12권3호
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• pp.67-78
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• 2021

모듈러주택은 세계대전 이후 신속하고 효율적인 주택공급을 위해 시도되었다. 국내에서도 30년 이상 품질 및 시공방법 개선을 위한 노력을 했으나 경쟁력있는 주택 상품이 되진 못했다. 모듈러 주택은 라멘구조로 평면구성을 자유롭게 할 수 있지만, 대부분 벽식 구조의 일반적인 아파트 평면을 분절한 형태로 변형하여 시공한다. 모듈러 주택의 생산 및 구조적 측면의 장점을 강화하기 위해서는 평면, 건축 구성재의 부품화 및 표준화, 자재, 제작 및 시공법, 공정관리, 공사비 관리 등 종합적인 측면에서 자동차와 같이 공장생산 시스템에 적합한 모델을 발전시키는 것이 필요하다. 본 연구에서는 생산 및 호환을 위해 MC(Modular Coordination)설계원칙을 적용하여 운반 및 생산 용이한 3m×3m 모듈을 공간의 기본 단위로 설정했다. 빌트인 가구를 포함한 3m×3m공간을 다양한 형태의 제품과 같이 생산하고, 이를 거주자의 기호에 맞게 조합하여 46m² 평면을 완성하는 방법을 제시했다. 생산설비, 운송수단, 시공크레인에 따라 생산 모듈을 다르게 설정할 수 있으며 운반장비가 소형화될수록 생산모듈의 가짓수도 적어질 수 있다. 이와같은 모듈러 주택 생산방식은 거주자의 요구에 맞춰 다양한 평면의 주택을 제공하기에 용이하고, 기술과 시스템의 발전에 따라 시공속도도 가속화할 수 있을 것이다.

• Steel and Composite Structures
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• 제20권1호
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• pp.127-145
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• 2016

Composite column design is strongly influenced by the computation of the critical buckling load, which is very sensitive to the effective flexural stiffness (EI) of the column. Because of this, the behaviour of a composite column under lateral loading and its response to deflection is largely determined by the EI of the member. Thus, prediction models used for composite member design should accurately mirror this behaviour. However, EI varies due to several design parameters, and the implementation of high-strength materials, which are not considered by the current composite design codes of practice. The reliability of the design methods from six codes of practice (i.e., AS 5100, AS/NZS 2327, Eurocode 4, AISC 2010, ACI 318, and AIJ) for composite columns is studied in this paper. Also, the reliability of these codes of practice against a serviceability limit state criterion are estimated based on the combined use of the test-based statistical procedure proposed by Johnson and Huang (1997) and Monte Carlo simulations. The composite columns database includes 100 tests of circular concrete-filled tubes, rectangular concrete-filled tubes, and concrete-encased steel composite columns. A summary of the reliability analysis procedure and the evaluated reliability indices are provided. The reasons for the reliability analysis results are discussed to provide useful insight and supporting information for a possible revision of available codes of practice.

• 디지털융복합연구
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• 제11권12호
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• pp.333-338
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• 2013

본 논문은 스마트폰에서 건축설계를 할 수 있도록 3D로 설계과정을 표현하였다. 먼저 건축자재들을 컴포넌트로 구성하고 컴포넌트들을 패턴으로 조립하여 패턴 단위로 건축설계가 이루어지도록 하였다. 모바일 환경에서 건축설계가 이루어 질수 있도록 4가지의 View로 구성하여 각각의 기능을 기술하였다. 또한 각 View에서 필요한 기술들을 사용된 라이브러리를 통하여 자세히 설명하였다. 이러한 구현 기술을 바탕으로 각 View가 어떻게 그 기능을 수행하여 서로 상호 보완적인 방법으로 동작하는지 그 과정과 자재 계산 결과들을 모바일을 통하여 보여주었다.

• 한국방재학회 논문집
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• 제10권1호
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• pp.1-7
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• 2010

최근 급속도로 가속화되는 농촌인구의 고령화 등으로 인해 농촌시설물도 기업화, 대형화, 대공간 시설물로 변경되어야 할 필요성이 있다. 이 논문에서는 현행 한국형유리온실의 대표적인 시스템인 벤로형 유리온실을 장경간화하기 위해 변단면 부재를 이용한 선설계기법을 적용하여 최적의 구조시스템을 개발하였다. 설계하중은 기존의 설계기준들을 검토하여 합리적인 값들을 적용하였다. 그 결과 스팬이 16 m 이상인 구조시스템에서 선설계기법을 적용하면 효율적이었으며 종방향 간격도 기존의 4 m 보다는 12 m로 증가시키는 것이 철골물량측면에서 유리함을 알 수 있었다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.643-648
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• 2005

Generally, ships have marks of various shapes on outside of the hull. Among them, so called "Draft Mark" indicates the distance from the bottom of the keel to the waterline. Draft marks are used to determine the displacement and other properties of the ship for stability and control purposes. These marks are made up of welding bead or sticking the steel plate on outside of the hull. To improve the confidence level of the ship owner, quality and accuracy of the draft mark is very important. So the automatic mark welding robot is used to enable a high quality and accurate manufacturing line. To improve the system portability, the system is divided into two distinct parts, namely mechanical part and control part. Mechanical part is robust, a lightweight, and easy to dismantle. The control part consists of an in-house developed controller, which is based on embedded Linux. Also, the control part consists of power line communication module to ensure the applicability of the controller in manufacturing line. In this paper, the methodologies of control and configuration of the robot are discussed.

• KIEAE Journal
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• 제9권2호
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• pp.73-80
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• 2009

In the early twentieth century, many architects still practised eclectic design elements. Emergence of new building materials such as steel, concrete and glass were not yet found fresh roles in architectural design. It was Brussels that the use of modern materials gave rise to their new forms and gave influence to not only building skins but also spatial organization. Art Nouveau architecture is often seen as revolutionary and pioneering modern architecture against eclectic classicism prevalent in the 18th and 19th centuries. Despite the fact that some scholars point out that Art Nouveau is more a transient phenomenon than modern architecture proper, no one would deny that Art Nouveau carries a good deal of modern characteristics. This paper intends to show rather ambivalent perspectives upon Art Nouveau architecture. Although it insinuates overly dynamic nature in architectural languages, it does not hamper us from reading Art Nouveau as a vital component of modern architecture. Through a careful analysis of the early domestic designs of Victor Horta, it becomes evident that his work can provide modern architecture a meaningful alibi for its growth. Victor Horta's house design is well known to the public, both for his classical tastes and for its changing implementation. Horta's modern quality is never adequately recognized, partly due to his eye catching modern iron properties and sinuous ornamentation. This paper tries to offer an insight into the complicated stage set of the fin-de-$si{\grave{e}}cle$ through the work of Victor Horta whose influence has been immense in the making of modern architecture.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.296-301
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• 2003

A study on the engineering design and numerical thermo-hydraulic analysis for KSTAR TF coil structure cooling system has been conducted. The numerical analyses have been done to verify the engineering design of cooling using the commercial code, FLUENT and in-house code for calculating helium properties which varies with cooling tube's heat transfer. Through the engineering design process based on the steady heat balance concepts, the circular stainless steel tube with inner diameter of 4 mm for TF coil has been selected as cooling tube. From normal operation mode analysis results, total 28 cooling tubes were finally chosen. Also, three dimensional cool down analysis for TF coil with designed cooling tube was satisfied with next three design criteria. First is cooling work termination within a month, second is maximum temperature difference within 50 K in TF coil structure and third is exit helium pressure above 2 bar. Consequently, these cool down scenario results can afford to adopt as operating scenario data when KSTAR facilities operate.

• 한국기계가공학회지
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• 제8권4호
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• pp.69-75
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• 2009

Recently developed automotive components are getting lighter providing a higher fuel efficiency and performance. Following the current trend, this study proposes a structural optimization method for the lower control arm installed at the front side of a Vehicle. Lightweight design of lower control arm can be achieved through design and material technology. In this research, the shape of lower control arm was determined by applying the optimization technology and aluminum was selected as a steel-substitute material. Strength performance is the most important design requirement in the structural design of a control arm. This study considers the static strength in the optimization process. For the optimum design, the durability analysis is performed to predict its fatigue life. In this study, the kriging interpolation method is adopted to obtain the minimum weight satisfying the strength constraint. Optimum designs are obtained by the in-house program, EXCEL-Kriging. Also, based on the optimum model obtained for the static strength, the optimization of Index of Fatigue Durability is carried out to get th optimum fatigue performance.

• Journal of Welding and Joining
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• 제29권5호
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• pp.63-71
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• 2011

Three-dimensional finite element analysis is performed to study the temperature distribution phenomenon of TIG assisted friction stir welding (TAFSW) between dissimilar plates (Al 6061-T6 and stainless steel 304). TAFSW is a solid-state welding process that integrates TIG (Tungsten Inert Gas) into a friction stir welding (FSW), to preheat the harder material ahead of FSW tool during welding. In order to facilitate the industrial application of welding, 3D numerical modeling of heat transfer has been carried out applying Finite Element Method (FEM). The temperature distribution due to heat generation during TAFSW on dissimilar materials joint is analysed using in-house solver. Moving heat source along with frictional heat between the work specimens and tool surface is considered to calculate the heat input. The analytical model used predicts successfully the maximum welding temperatures that occur on the dissimilar materials during TAFSW. Comparison with the infra red camera and thermocouple measurement results shows that the results from the current numerical simulation have good agreement with the measured data.