• 대한기계학회논문집A
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• 제35권10호
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• pp.1171-1178
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• 2011

본 논문은 동적 시스템인 구동기의 강건설계를 수행한 결과를 제시한다. 구동기를 구성하는 부품들의 변량은 구동기의 성능에 변량을 유발한다. 따라서 부품들의 변량에 둔감한 구동기의 성능을 확보하기 위해 구동기에 대해서 강건설계를 수행하였다. 구동기를 구성하는 부품들을 전달함수로 표현하여 시뮬링크 모델로 구축하였으며, 시뮬링크 모델을 이용하여 설계 변수 조합에 따른 구동기의 응답을 얻었다. 또한 반응표면법을 적용하여 구동기의 응답을 설계 변수들의 2차 함수로 근사화하였다. 구동기응답을 출력으로 하는 근사화된 모델에 확률적 설계방법을 적용하여 강건한 구동기의 성능을 위한 최적 설계변수를 결정하고 기존 설계와 비교한 결과를 제시하였다.

• 한국산학기술학회논문지
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• 제20권12호
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• pp.475-481
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• 2019

건축물의 생애주기 전반에 걸쳐 중요한 영향을 줄 수 있는 건축물의 성능과 관련하여, 설계 초기단계에서 계획안의 환경성능을 검토할 수 있는 디자인 피드백의 중요성이 점차 부각되고 있다. 그런데, 건설산업 특성에 따른 전문분야 도메인 구분으로 인해, 서로 다른 어플리케이션 사이에서 데이터 호환성의 문제에 따른 제약이 많은 실정이다. 이에, 지식기반 디자인 방법론에 기반하여, 본 연구는 건축물의 형상과 연동 가능한 BIM 객체의 기하정보에 대한 상관관계 정보체계를 제안하도록 한다. 이를 위해, 오피스 건축물의 기획 및 계획설계 단계를 대상으로, 상용 BIM 시스템인 Autodesk Revit을 활용하여 매스 형상에 파라메트릭 제약조건을 설정한다. 나아가, 오피스 매스의 형상정보와 양방향 프로세스로 연동가능하도록, Autodek Green Building Studio 엔진에서 분석가능한 해석모델로 변환함으로써, 파라미터에 의한 형태 변형에 따른 다양한 대안들에 대하여 실내조도 성능을 시뮬레이션한다. 이를 통해, 디자인 조건들을 만족시켜주는 범위 내에서 적절한 환경성능의 검토가 가능한 정량적인 의사결정 방법을 제시하고자 한다.

• 한국연소학회:학술대회논문집
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• 한국연소학회 1997년도 제15회 KOSCO SYMPOSIUM 논문집
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• pp.135-151
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• 1997

The preliminary design and performance test for determining dimensions of gas turbine combustor were investigated. The combustor design program was developed and applied to design our combustor. and detailed design for determining of swirler. dome and liner holes were performed experimentally. The swirler. which govern the combustion characteristics of combustor, was determined $40^{\circ}$ as swirl angle at first performance test. After second performance test the swirler was re-determined by 24 mm i.d.. 34 mm o.d., and swirl angle of $45^{\circ}$. The geometry of liner holes were determined by considering the flame stability and recirculation zone size. It was found that flame can be more easily stabilized by adjusting the swirier dimensions rather than liner holes. The geometry of swirler and liner holes were re-determined by final performance test with dilution holes. Also. the performance of combustor was evaluated by analysis of exhaust gases.

• Earthquakes and Structures
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• 제10권4호
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• pp.735-755
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• 2016

This article presents a proposed analytical methodology to determine seismic force-resisting system R-values for steel diagrid framed systems. As current model building codes do not explicitly address the seismic design performance factors for this new and emerging structural system, the purpose of this study is to provide a sound and reliable basis for defining such seismic design parameters. An approach and methodology for the reliable determination of seismic performance factors for use in the design of steel diagrid framed structural systems is proposed. The recommended methodology is based on current state-of-the-art and state-of-the practice methods including structural nonlinear dynamic analysis techniques, testing data requirements, building code design procedures and earthquake ground motion characterization. In determining appropriate seismic performance factors (R, ${\Omega}_O$, $C_d$) for new archetypical building structural systems, the methodology defines acceptably low values of probability against collapse under maximum considered earthquake ground shaking.

• 설비공학논문집
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• 제16권9호
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• pp.779-787
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• 2004

Design and off-design program is set up to analyze the performance of a plate heat exchanger. The program is verified by comparing the results with the experiment. The comparison shows that the predicted overall heat transfer coefficients are in good agreement with the measurements. Also the off-design performance according to the variations of inlet water temperature, flow rate, and the number of plates is analyzed to study the performance characteristic of a plate heat exchanger.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2011년도 춘계 학술논문 발표대회 1부
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• pp.207-209
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• 2011

Numerous reports show that alternative project delivery systems (PDSs) such as design-build (DB), construction management at risk (CMR), and design-build-maintain (DBM) are increasingly used in many countries. This study compared characteristics of each PDS (design-bid-build (DBB), DB, CMR, or DBM) by analyzing quantitative data from 9 research articles. In order to compare characteristics between DBB and alternative PDSs, the study is based on principal 3 factors - Time, Cost, and Quality. DB shows the best performance in the time part and also the cost performance depending on facility type and project size. The performance of quality has minor difference among different PDSs. These results support the fact that using an appropriate PDS by the characteristic of a project makes high value of efficiency and productivity.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 추계학술대회 논문집
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• pp.1012-1017
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• 2008

In this study, We examine closely the capacity spectrum method which a kind of displacement-based method evaluated by displacement of structure as an alternative to the load-based analysis method. The displacement-based method can easily review the strength of structure, seismic performance, ductility. Seismic performance by using capacity spectrum method is divided into design response spectrum and capacity spectrum. We can diagram design response spectrum by deciding the design seismic factor depending on performance target, site classification, seismic level, return period as UBC-97. Capacity spectrum is a load-displacement curve obtained by Push-over analysis considering the geometric parameter and the material parameter. We execute the seismic performance evaluation by using the capacity spectrum method to reinforced concrete pier which has been seismic design. As a result, We confirmed that there is a yield point and a ultimate point close by design response spectrum of UBC-97.

• Wind and Structures
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• 제37권2호
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• pp.117-131
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• 2023

Korea Design Standard (KDS) will be updated with two major revisions on the assessment of wind load and performance-based wind design (PBWD). Major changes on the wind load assessment are the wind load factor and basic wind speed. Wind load factor in KDS is reduced from 1.3 to 1, and mean recurrence interval (MRI) for basic wind speed increases from 100 years to 500 years considering the reduction of wind load factor. Additional modification is made including pressure coefficient, torsional moment coefficient and spectrum, and aeroelastic instability. Combined effect of the updates of KDS code on the assessment of wind load is discussed with the case study on the specified sites and building. PBWD is newly added in KDS code to consider the cases with various target performance, vortex-induced vibration, aeroelastic instability, or inelastic behavior. Proposed methods and target performance for PBWD in KDS code are introduced.

• Educational Technology International
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• 제10권2호
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• pp.1-27
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• 2009

Technology use can dramatically enhance teachers' performance in teaching and administrative tasks. An Electronic Performance Support System (EPSS) is a versatile tool that could provide just-in-time and on-the-job training when teachers need it. In order to design an effective EPSS for teachers, it is critical to identify their needs. This study used interviews to identify teachers' needs for technology by asking them about their workloads, the difficulty and time demands of tasks, and useful technologies. The implications of the findings for the design of an EPSS are discussed, including the necessity of an adaptive design of the EPSS.

• Steel and Composite Structures
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• 제5권2_3호
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• pp.159-168
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• 2005

Four design codes/regulations for steel structures in Japan are briefly reviewed. Some of them employ the limit state design concept while the others are still based on the allowable stress design concept. The process for revision is now in action. The directions in the development of structural design codes are also reported herein. It is noted that a current trend in this development is to employ the performance-based design concept that has been successfully implemented in some seismic design codes.