• Wind and Structures
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• 제7권6호
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• pp.393-404
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• 2004

The design of truss type sign support structures is based on the guidelines provided by the American Association of State Highway and Transportation Officials Standard Specifications for Highway Signs, Luminaries and Traffic Signals and the American Institute of Steel Construction Design Specifications. Using these specifications, the column design strength is normally determined using the effective length approach. This approach does not always accurately address all issues associated with frame stability, including the actual end conditions of the individual members, variations of the loads in the members, and the resulting sidesway buckling for truss type sign support structures. This paper provides insight into the problems with the simplified design approach for determining the effective lengths and discusses different approaches for overcoming these simplifications. A system buckling approach, also known as a rational buckling analysis, is used in this study to determine improved predictions for design strength of truss type sign support structures.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2001년도 가을 학술발표회 논문집
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• pp.201-210
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• 2001

In this study, large-scale distributed design approach for a life cycle cost (LCC) optimization of steel box girder bridges was implemented. A collaborative optimization approach is one of the multidisciplinary design optimization approaches and it has been proven to be best suited for distributed design environment. The problem of optimum LCC design of steel box girder bridges is formulated as that of minimization of the expected total LCC that consists of initial cost maintenance cost expected retrofit costs for strength, deflection and crack. To discuss the possibility of the application for the collaborative optimization of steel box girder bridges, the results of this algorithm are compared with those of single level algorithm. From the numerical investigations, the collaborative optimization approach proposed in this study may be expected to be new concepts and design methodologies associated with the LCC approach.

• 국제학술발표논문집
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• The 2th International Conference on Construction Engineering and Project Management
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• pp.356-365
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• 2007

The development in the design process is usually based on the choice of a method for designing the system, in which this method is frequently faced with tightening environmental requirements, reducing development cycle times and growing complexity. To tackle such factors, the paper proposes a comprehensive approach focusing on applying systems engineering approach to the building design support. In particular, this paper addresses all capabilities of using some available systems engineering standards (like EIA-632) in the design process. Then, a methodological approach is proposed for the practice of requirements engineering by applying quality assessment and control to design in early phase. The paradigm used, here is to extend and particularly to adapt the work carried out in military and space systems to modern building services by taking into account the semantics of buildings in terms of different engineering fields and architecture issues.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 춘계 학술발표회 논문집
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• pp.17-24
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• 2005

Recently construction activities increase in reclaimed onshore areas. It is therefore considered an important factor for the design of pile foundation with problems in terms of settlements due to soft grounds. Nevertheless the design of piles for negative skin friction(or downdrag forces) is probably poorly understood by many engineers. It is mainly because the most of design specification give a way to design pile foundation in bearing capacity aspect although the negative skin friction is related to settlement(downdrag). Under LRFD(load resistance factor design) approach it is to separately consider ultimate limit state and serviceability limit state. This paper discusses LRFD approach to the design of piles for negative skin friction and compares this approach to traditional design approach. And also a case history is analyzed in that point of view.

• International Journal of Concrete Structures and Materials
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• 제2권2호
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• pp.137-143
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• 2008

In recent years, much research work has been performed on durability design and long-term performance of concrete structures in marine environments. In particular, the development of new procedures for probability-based durability design has been shown to provide a more realistic basis for the analysis. This approach has been successfully applied to several new concrete structures, where requirements for a more controlled durability and service life have been specified. For reinforced concrete structures in a marine environment, it is commonly assumed that the dominant degradation mechanism is the corrosion of the reinforcement due to the presence of chlorides. The design approach is based on the verification of durability limit states, examples of which are: depassivation of reinforcement, cracking and spalling due to corrosion, and collapse due to cross section loss of reinforcement. With this design approach the probability of failure can be determined as a function of time. In the present paper, a probability-based durability performance analysis is used in order to demonstrate the importance of the durability design approach of concrete structures in marine environments. In addition, the sensitivity of the various durability parameters affecting and controlling the durability of concrete structures in a marine environment is studied. Results show that the potential of this approach to assist durability design decisions making process is great. Based the crucial information generated, it is possible to prolong the service life of structures while simultaneously optimizing the final design solution.

• 디자인학연구
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• 제18권2호
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• pp.233-242
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• 2005

본 연구는 디자인의 사회사가 한국디자인의 역사를 연구하고 교육하는데 있어서 하나의 유용한 방법론이 될 수 있는가 하는 문제의식에서 출발하였다. 디자인에 대한 사회사적 접근방식을 이해하기 위해 우선 제2장에서는 니콜라우스 페브스너 이래 지속되어 온 디자이너 중심의 디자인사 서술 방식과 이를 비판하며 사회사적 관점의 디자인사를 주장했던 에이드리언 포티의 디자인사 서술 방식을 비교하였다. 제3장에서는 한국 근현대기 일상문화와 시각문화에 대한 사회문화적 접근을 시도했던 <일상 기억 역사>, <캠페인을 보면 사회가 보인다>, <신화 없는 탄생: 한국 디자인 1910 - 1960> 등 세 개의 국내 전시회를 통해 한국디자인에 대한 사회사적 접근 방식의 사례를 찾아보고자 했다. 제4장에서는 디자인사 연구와 교육에 있어서 디자인의 사회사적 접근 방식이 갖는 의미와 특성 등을 고찰해보고 질적연구방법론 도입의 필요성에 대해서 논하였다.

• 시스템엔지니어링학술지
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• 제3권2호
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• pp.39-48
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• 2007

In this study, an overall product design process will be presented by using the Analytic Hierarchy Process(AHP) and robust design. From the conceptual design stage, the logical methods are used to select the appropriate concepts satisfying the customer requirements and the other conditions. The next phase is the embodiment design phase in which the deterministic and robust design approach are used to obtain the improvement in product design. Typically, this approach is applied for developing the simple bookshelf design. The results show the efficient approach which can be supported to develop the new product.

• International Journal of CAD/CAM
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• 제3권1_2호
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• pp.67-75
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• 2003

Viewpoint-dependent feature-based modelling in computer-aided design is developed for the purposes of supporting engineering design representation and automation. The approach of this paper uses a combination of a multi-level modelling approach. This has two stages of mapping between models, and the multi-level model approach is implemented in three-level architecture. Top of this level is a feature-based description for each viewpoint, comprising a combination of form features and other features such as loads and constraints for analysis. The middle level is an executable representation of the feature model. The bottom of this multi-level modelling is a evaluation of a feature-based CAD model obtained by executable feature representations defined in the middle level. The mappings involved in the system comprise firstly, mapping between the top level feature representations associated with different viewpoints, for example for the geometric simplification and addition of boundary conditions associated with moving from a design model to an analysis model, and secondly mapping between the top level and the middle level representations in which the feature model is transformed into the executable representation. Because an executable representation is used as the intermediate layer, the low level evaluation can be active. The example will be implemented with an analysis model which is evaluated and for which results are output. This multi-level modelling approach will be investigated within the framework aimed for the design automation with a feature-based model.

• Advances in Computational Design
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• 제1권1호
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• pp.87-103
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• 2016

This paper adopts and investigates the non-dominated sorting approach for extending the single-objective Cuckoo Search (CS) into a multi-objective framework. The proposed approach uses an archive composed of primary and secondary population to select and keep the non-dominated solutions at each generation instead of pairwise analogy used in the original Multi-objective Cuckoo Search (MOCS). Our simulations show that such a low computational complexity approach can enrich CS to incorporate multi-objective needs instead of considering multiple eggs for cuckoos used in the original MOCS. The proposed MOCS is tested on a set of multi-objective optimization problems and two well-studied engineering design optimization problems. Compared to MOCS and some other available multi-objective algorithms such as NSGA-II, our approach is found to be competitive while benefiting simplicity. Moreover, the proposed approach is simpler and is capable of finding a wide spread of solutions with good coverage and convergence to true Pareto optimal fronts.

• 한국조사연구학회:학술대회논문집
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• 한국조사연구학회 2001년도 춘계학술논문발표대회 발표논문집
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• pp.45-56
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• 2001

복합표본조사 데이터 분석에서 회귀모형 접근법은 크게 표본설계 기반 접근법(design-based approach)과 일반화 추정 방정식 접근법(generalized estimating equations approach)으로 구분된다. 본 논문은 이들 접근법과 모형기반 접근법을 비교하여 설명하고, 각 접근법에서 표본설계가 모수 추정에 미치는 영향을 설계 효과와 가중치 효과 분석을 통해서 살펴보았다.