구조물의 동특성추정을 위한 개선된 주파수영역 기법

홍규선,윤정방,Hong, Kyu Seon,Yun, Chung Bang 대한토목학회 1993 대한토목학회논문집 Vol.13 No.2

주파수응답함수는 주파수영역에서 구조물의 동특성을 추정하는데 있어 가장 중요하고 기본이 되는 것이다. 본 논문에서는 주파수응답함수의 추정을 위한 개선된 방법을 제안하였다. 제안된 주파수응답 함수는 종래의 주파수응답함수 산정 방법인 $H_1$(f)와 $H_2$(f)의 가중평균으로 구성되었다. 이것은 $H_2$(f)가 공진주파수영역에서 더 정확한 결과를 주는 반면, $H_1$(f)는 비공진주파수영역에서 더 좋은 결과를 주는 특성을 이용한 것이다. 본 논문에서 제안한 방법의 타당성을 검증하기 위하여, 수치모의실험과 함께 실제 실험을 수행하여 얻어진 데이타를 분석하였다. 해석 결과로 부터, 새로이 제안된 주파수응답함수가 다른 주파수응답함수에 비해 좀 더 정확한 결과를 줌을 확인할 수 있었다. Frequency response functions(FRF) are the most fundamental data for the frequency domain identifications of structural systems. In this paper, an improved method for estimating FRF's is presented. The new FRF estimator takes the weighted average of two conventional estimators, $H_1$(f) and $H_2$(f), utilizing the fact that $H_2$(f) gives more accurate estimate at resonance, while $H_1$(f) yields better results at antiresonances. Based on the estimated FRF's, the modal parameters of the structures, such as, natural frequencies, damping ratios and mode shapes, are also estimated. The effectiveness of the proposed method is investigated through numerical and experimental studies. The estimated results indicate that the proposed estimator gives more accurate results than other estimators.

2차 모우드 섭동법에 의한 구조물의 손상도 추정

홍규선,윤정방,류정선 한국전산구조공학회 1992 전산구조공학 Vol.5 No.3

교량, 발전소, 해양구조물과 같은 토목구조물은 사용기간중에 지진, 바람, 파랑하중등에 의해 구조적 손상을 받기 쉽다. 장기간에 걸쳐 구조물에 손상이 누적되면 구조물 전체의 파괴를 초래할 수도 있다. 따라서 현존하는 구조물의 안전성을 분석하기 위한 구조물의 손상도를 추정하는 방법이 필요하다. 본 논문에서는 Inverse Modal Perturbation기법을 이용하여 구조물의 손상도를 추정하는 방법에 대하여 연구하였다. Perturbation식은 구조물의 강성 및 질량행렬의 변화량과 구조물의 고유진동수와 모우드형상의 변화량의 식으로 구성된다. 또한 구조물의 손상은 강성행렬의 변화량으로 표현하였다. 본 연구에서는 구조물의 손상도추정의 효율성을 증대시키기 위하여 2차-Perturbation식을 구성하고, 이것을 반복적인 절차를 거쳐 해를 구하는 방법에 대하여 연구하였다. 제안된 방법의 효율성은 일련의 예제해석을 통하여 검증하였으며, 추정된 결과로 부터 본 방법이 구조물의 손상을 적절히 산정함을 알 수 있었다. Most civil engineering structures such as bridges, power plants, and offshore platforms are apt to suffer structural damages over their service lives caused by adverse loadings, such as earthquakes, wind and wave forces. Accumulation of structural damages over a long period of time might cause catastrophic structural failure. Therefore, a methodology for monitoring the structural integrity is essential for assuring the safety of the existing structures. A method for the damage assessment of structures by the second order inverse modal perturbation technique is presented in this paper. Perturbation equation consists of a matrix equation involving matrices of structural changes(stiffness and mass matrix changes) and matrices of modal property changes(natural frequency and mode shape changes). The damages of a structure are represented as changes in the stiffness matrix. In this study, a second order perturbation equation is formulated for the damage assessment of structures, and solved by an iterative procedure. The effectiveness of the proposed method has been investigated through a series of example analysis. The estimated results for the structural damage indicated that the present method yields resonable estimates for the structural changes.

바이오미미크리에 기반을 둔 건축디자인 사례연구 - 바이오모피즘(Biomorphism)에서 바이오미미크리(Biomimicry)로의 통시적 변화를 중심으로

홍규선,조현의,이성재 한국문화공간건축학회 2016 한국문화공간건축학회논문집 Vol.- No.54

As bio-technology develops and accumulates, the more we realize the shallowness of our current knowledge about surrounding nature. Biomimicry is a field of research sorting out numerous wisdom and recognizing inspiration from nature through 3.8 billion-years’ successful self-proven history to solve our impending problems with far greater efficiency. To understand properly the concept and its’ trends of biomimicry, the research follows several steps. Firstly, the holistic concept and historic traces of biomimicry was analyzed diachronically through the literature study. Secondly, 26 biomimicry relevant architectural precedents were collected from the search of the relevant literature and the internet. Thirdly, those collected examples were analyzed by 4 inspirational criteria; Form & Space, Function & Structure, Response & Kinetics, Integrated System to understand the latest trends of biomimicry architecture and to foresee the desirable directions of it. The results from the research shows the trends of biomorphic architecture is shifting into the preference of biomimicry architecture pursuing an self-supporting efficient city, which can close the open loop of our current eco-system with solutions for our impending environmental problems.

국내도매여행업 브랜드의 이미지 포지셔닝에 관한 연구

홍규선,안택균 문화관광연구학회 2001 문화관광연구 Vol.3 No.1

The purpose of this study was to evaluate positioning of the brand image in travel industry. To achieve the purpose of this study, theoretical and empirical study was used. In review of theoretical background, basic concepts and strategy of brand image positioning were studied. Based on the theoretical studies and previous studies, brand image attributes were chosen. An empirical study was conducted with cases of Hana Tour, Freedom Travel Service, Mode Tour, High-Sense Travel Service, Lotte Tour, Hanjin Travel Service. And a list of questions in five categories-brand similarity, perception for attributes, brand image preference, importance for attributes, and personal characteristics of respondents-were constructed and tested. In this research 8 brand images attributes was discussed, they are easiness of remember, easiness of pronunciation, familiarity of brand, good thoughts of brand, freshness(newness) of brand, speciality(originality) of brand, an attribute in connection with product price, an attribute in connection with product quality. The ultimate objectives of this study is to suggest the effective direction to set up a brand positioning strategy by using brand images. But this study had limits on sampling was extracted six travel agencies because of time limitation. Therefore, the more systematic and continuos study should be executed to overcome those kind of limits.

2차 모우드 섭동법에 의한 구조물의 손상도 추정

홍규선,윤정방,류정선 한국전산구조공학회 1992 한국전산구조공학회논문집 Vol.5 No.3

교량, 발전소, 해양구조물과 같은 토목구조물은 사용기간중에 지진, 바람, 파랑하중등에 의해 구조적 손상을 받기 쉽다. 장기간에 걸쳐 구조물에 손상이 누적되면 구조물 전체의 파괴를 초래할 수도 있다. 따라서 현존하는 구조물의 안전성을 분석하기 위한 구조물의 손상도를 추정하는 방법이 필요하다. 본 논문에서는 Inverse Modal Perturbation기법을 이용하여 구조물의 손상도를 추정하는 방법에 대하여 연구하였다. Perturbation식은 구조물의 강성 및 질량행렬의 변화량과 구조물의 고유진동수와 모우드형상의 변화량의 식으로 구성된다. 또한 구조물의 손상은 강성행렬의 변화량으로 표현하였다. 본 연구에서는 구조물의 손상도추정의 효율성을 증대시키기 위하여 2차-Perturbation식을 구성하고, 이것을 반복적인 절차를 거쳐 해를 구하는 방법에 대하여 연구하였다. 제안된 방법의 효율성은 일련의 예제해석을 통하여 검증하였으며, 추정된 결과로 부터 본 방법이 구조물의 손상을 적절히 산정함을 알 수 있었다. Most civil engineering structures such as bridges, power plants, and offshore platforms are apt to suffer structural damages over their service lives caused by adverse loadings, such as earthquakes, wind and wave forces. Accumulation of structural damages over a long period of time might cause catastrophic structural failure. Therefore, a methodology for monitoring the structural integrity is essential for assuring the safety of the existing structures. A method for the damage assessment of structures by the second order inverse modal perturbation technique is presented in this paper. Perturbation equation consists of a matrix equation involving matrices of structural changes(stiffness and mass matrix changes) and matrices of modal property changes(natural frequency and mode shape changes). The damages of a structure are represented as changes in the stiffness matrix. In this study, a second order perturbation equation is formulated for the damage assessment of structures, and solved by an iterative procedure. The effectiveness of the proposed method has been investigated through a series of example analysis. The estimated results for the structural damage indicated that the present method yields resonable estimates for the structural changes.

친환경 건축의 심미성 발현 경향에 대한 연구 - AIA TOP10 사례를 중심으로 -

홍규선,이성재 한국문화공간건축학회 2017 한국문화공간건축학회논문집 Vol.- No.59

Considering a broad consensus on it, Eco-friendly architecture is not a question whether to do it but how to conduct it. From this point of view, it is a critical question for contemporary architects; how eco-friendly architecture has influenced so far and will affect the aesthetic developments of architecture in the upcoming era. For this reason, the purpose of this study is to examine the trends of aesthetic manifestation in eco-friendly architecture based on a balanced standard including the technical and non-technical factors through the case analysis of AIA Top10 projects, which accumulates credible resources regarding the sustainable architectural projects since 1998. In addition, to establish a balanced standard for a case analysis, 6 criteria were derived from the previous studies: Energy Efficiency, Resource Efficiency, Environmental Form, Eco-Cultural, Eco-Social, and Eco-Health. Through the case analysis, we confirmed that the non-technical factors have a relatively high frequency of aesthetical manifestation of Eco-friendly architecture, and Environmental Form plays the most evident role among them. On the other hand, in case of 'technical factors', the number of architectural application is high, but the expression of environmental aesthetics is relatively low. Simultaneously, an acceptable range of architectural beauty has been gradually getting wider from direct visual stimuli to empirical relative participations and community & region based sharing processes aligned with the direction of Eco-Cultural and Eco-Social, which will be a potential research area for further aesthetic developments of architecture.

항공사의 연합패키지 상품 활성화 방안에 관한 연구 : 유럽 지역 항공사를 중심으로 Focused on European carrier

홍규선 문화관광연구학회 2003 문화관광연구 Vol.5 No.1

The purpose of this study is how can maximize the market of consolidation package in europe bound. Recently, European carrier introduced new type of package, consolidation package which is contributed to boost up benefit cost on airlines. Consolidation package is wide spread to all airlines in korea the reason why korean travel market is unstable according to seasonality. Therefore airlines are trying to avoid low yield of off season and achieve their target. In order to raise up to the foundation stone in travel package market, Airlines have to develope many kinds of consolidation package. Consolidation package can break off seasonality and economical crisis in airline industry. Airlines consolidation package should be enforced to manage package travel agents with proper way as like familiarization tour and be invested to develope new competitive products. Airlines and travel agents are unable to divide in tourism industry, Both have to co-operate and pursuit bilateral win-win strategy. That will be followed development of tourism industry.

복합모형을 이용한 점탄성지반의 지반-구조물 상관관계

홍규선,윤정방,Hong, Kyu Seon,Yun, Chung Bang 대한토목학회 1986 대한토목학회논문집 Vol.6 No.1

본 논문에서는 점탄성지반의 지반-구조물 시스템을 해석하는 복합모형기법이 연구되었다. 복합모형은 지반-구조물 시스템을 구조물과 구조물주위의 반구형태의 지반으로 구성된 내부영역과 반구바깥부분의 외부영역으로 나누어 해석하는 방법으로서, 내부영역은 유한요소로 모형화하고 외부영역은 주파수 종속 임피던스로 나타낸다. 점탄성지반에 대한 외부영역 임피던스는 탄성지반에 대하여 구한 임피던스함수에 Hysteretic damping항을 더해주는 방법을 사용하였으며, 이에 대한 검증은 점탄성지반의 강체원형판에 대한 임피던스를 이론적인 값과 비교함으로써 수행되었다. 예제해석은 대형굴뚝에 대하여 수행되었으며, 해석결과를 자주 사용되는 다른 방법에 의한 결과와 비교 검토하였다. A hybrid modelling technique of a soil-structure system on viscoelastic soil medium is studied in this paper. The hybrid model consists of a near-field and a far-field with their common interface passing through the soil region at some distance from the base of the structure. It makes use of frequency-dependent impedances so as to represent the semi-infinite far-field. The far-field impedances are formulate including the radiation damping characteristics as well as the viscoelastic properties of the soil medium. The verification of the method has been carried out using a rigid circular plate on a viscoelastic half-space. The impedances obtained by the method are compared with the theoretical values. Example analyses have been performed for a tall chimney and the results have been compared with those obtained by other methods which are frequently used.

국내 항공운송업의 전략적 제휴에 관한 연구

홍규선 문화관광연구학회 2000 문화관광연구 Vol.2 No.2

The purpose of this study is showing the necessity and the direction of the strategic alliance in national airlines through analyzing the case of the strategic alliance in foreign countries and establishing the direction of the strategic alliance International service network through strong strategic alliance should be developed. The only way to survive in this tough situation is to expand the international network centered on Asia. Also, multiple hub transportation allocation system should be occupied. Lots of efforts are needed to possess steadily growing air transportation market in China and Asia. The airlines in Korea should try to have a strategic alliance with airlines in USA and Europe and the airlines in Korea should try to have a strategic alliance with service-oriented airlines. Nowadays, the number of airlines which try to take the initiative in the market through the qualitys of the service is getting increased. An outcome of the star alliance and one world which are the strategic alliance among airlines is tangible and strategic alliance among airlines is actively being done. Then, the airlines in Korea should grope for the way to join the star alliance or one world, or should make other strong alliance group by choosing mega airlines as a partner.

고령화사회진입에 따른 실버관광개발연구

홍규선(Hong, Kyu-Sun) 한국여행학회 2011 여행학연구 Vol.32 No.-

Recently, Silver aged people are tremendously increased therefore silver tourism development ought to be studied further more. There are so many problems are existed in silver era. Also, government have not make a completed law and fix the policy for silver aged people yet. There are few suggestions about silver tourism throughout this research. First, Government should make the law relevant silver tourism and support the fund to develop silver industry in Korea. Second, Silver resort have to be developed for the silver aged people. Third Medical Silvertel(Silver + Hotel) should be constructed in each province. Fourth, Government have to try to develop the products for silver and invest the finance for the purpose of silver industry deveolpment in the near future.