• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2006년도 추계학술발표논문집
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• pp.290-293
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• 2006

본 연구는 웹 기반 선례검색 시스템을 개발하였다. 기존의 연구들에 대한 사례 조사를 통해서 지금까지의 선례 검색 방법의 한계: 변환과정에서의 의미 손실과 자료 공유의 시공간제한성 밝혔다. 해결책으로 의미기반 공통표현모듈을 도입하고 웹 환경을 이용하여 효과적인 선례검색 해결방법을 찾아냄으로써 검색과 자료 공유가 용이한 선례검색 시스템을 개발했다.

• 생명과학회지
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• 제21권7호
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• pp.1009-1015
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• 2011

거미의 건축물인 웹의 구조는 먹이 포획을 위한 자원의 투자이자 그 자체가 포식 전략이다. 잠재적인 먹이종으로부터 제공되는 감각정보를 바탕으로 포식 전략을 수정하는 개체는 그렇지 못한 개체에 비해 더 높은 적응도를 가질 것이다. 본 연구는 공중에 둥근 웹을 건축하는 긴호랑거미(Argiope bruennichi)를 대상으로 자외선을 인식하는 비행성 곤충인 서양뒤영벌(Bombus terrestris)의 정보를 경험한 개체가 자신의 건축 행동을 수정하는지를 알아보기 위해 수행되었다. 서양뒤영벌(B. terrestris)의 정보를 제공받은 실험군의 개체가 건축한 웹의 구조를 대조군(정보 없음)의 웹과 비교하였다. 본 연구의 가설은 실험군 개체들은 웹과 흰띠줄 건축에 더 많은 투자를 할 것이라는 것이다. 실험 결과는 당초의 가설을 기각했다. 웹과 흰띠줄 건축은 실험군과 대조군 모두에서 전반적으로 감소하는 경향을 나타냈다. 개체는 꽃꿀채집자의 정보에도 불구하고 흰띠줄을 더 길게 만들지도 웹을 확장하지도 않았다.

• 한국습지학회지
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• 제13권1호
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• pp.139-148
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• 2011

거미의 웹 건축 행동은 먹이 사냥을 위한 투자 행동이며, 적극적인 포식 전략의 반영이다. 성공적인 포식전략 수립을 위해서 개체는 먹이 동물로부터 오는 감각 정보를 반영해야 할 것이다. 본 연구는 우리나라에 널리 분포하는 대표적 논거미인 긴호랑거미(Argiope bruennichi)의 건축 행동이 피식자인 왕귀뚜라미(Teleogryllus emma)에 의해 제공되는 감각 정보를 바탕으로 수정되는가를 알아보기 위해 수행되었다. 웹의 물리적 구조가 수정되는 양상을 보기 위해 감각 자극 전과 후에 건축된 웹의 구조를 정량적으로 측정하고 대조군과 비교 분석하였다. 먹이가 공급되지 않는 상황에서 웹 건축 행동을 보인 개체의 수는 대조군(자극 없음)과 실험군(자극 공급)에서 모두 감소하는 경향을 보였다. 대조군과 실험군에서 나타난 증감 양상이 뚜렷한 차이를 드러내 않았다. 왕귀뚜라미에 의한 자극 공급 1일째에 해당하는 날에 실험군 웹 건축 행동은 전일 대비 3.7% 감소한대 반해 대조군은 11.8% 감소하는 차이를 나타냈다. 흰띠줄 건축 행동 역시 전반적으로 감소하는 경향이 나타났다. 대조군에서 흰띠줄을 건축한 개체수가 자극 1일에 14.7% 감소한데 비해, 실험군에서는 7.4%로 두 배 가량 감소 경향이 낮게 나타났다. 본 실험 디자인에 의한 연구 결과는 개체가 감각 정보에 따라 웹의 높이와 넓이를 수정하지 않는 것으로 나타났다.

• Journal of Information Technology Applications and Management
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• 제17권4호
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• pp.39-56
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• 2010

We are sometimes interacting with people who we know nothing and facing with the difficult task of making decisions involving risk in social network. To reduce risk, the topic of building Web of trust is receiving considerable attention in social network. The easiest approach to build Web of trust will be to ask users to represent level of trust explicitly toward another users. However, there exists sparsity issue in Web of trust which is represented explicitly by users as well as it is difficult to urge users to express their level of trustworthiness. We propose a fuzzy-based inference model for Web of trust using user behavior information in social network. According to the experiment result which is applied in Epinions.com, the proposed model show improved connectivity in resulting Web of trust as well as reduced prediction error of trustworthiness compared to existing computational model.

• Steel and Composite Structures
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• 제8권5호
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• pp.389-402
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• 2008

In December 2005, one(A) of the two pre-engineered warehouse buildings in the port of K City of Korea was completely destroyed and the other(B) was seriously damaged to be demolished. Over-loaded snow and unexpected blast of wind were the causes of the accident and destructive behavior was brittle fracture caused by web local buckling and lateral torsional buckling at the flange below rafter. However, the architectural design technology of today based on material non-linear method does not consider the tolerances to solve the problem of such brittle fracture. So, geometric non-linear evaluation which includes initial deformation, width-thickness ratio, web stiffener and unbraced length is required. This study evaluates the structural safety of 4 models in terms of width-thickness ratio and unbraced length using ANSYS 9.0 with parameters such as width-thickness ratio of web, existence/non-existence of stiffener and unbraced length. The purpose of this study is to analyze destructive mechanism of the above-mentioned two warehouse buildings and to provide ways to promote the safety of pre-engineered buildings.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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• pp.897-902
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• 2001

The purpose of this experimental study is to investigate the shear behavior of high-strength concrete deep beam and to grasp the conservatism of ACI Building Code. Experimental results on 12 deep beams under two equal symmetrically placed point loads are reported. Main variables are vertical and horizontal web reinforcement and shear span-to-overall depth ratio. Test results indicated that web reinforcement dose not affect on formation of inclined cracks but shear span-to-overall depth ratio affect on inclined shear cracks and ultimate shear strength. Addition of vertical web reinforcement improves ultimate shear strength of H.S.C. deep beams that shear span-to-overall depth ratio is 1.0. Considerable increase in ultimate shear strength of H.S.C. deep beams with increasing horizontal web reinforcement that shear span-to-overall depth ratio is 0.5. Especially with increasing concrete strength($f_{ck}$) the ACI code is conservative in estamating the ultimate shear strength of deep beams.

• 한국데이타베이스학회:학술대회논문집
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• 한국데이타베이스학회 2010년도 춘계국제학술대회
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• pp.277-287
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• 2010

We are sometimes interacting with people who we know nothing and facing with the difficult task of making decisions involving risk in social network. To reduce risk, the topic of building Web of trust is receiving considerable attention in social network. The easiest approach to build Web of trust will be to ask users to represent level of trust explicitly toward another users. However, there exists sparsity issue in Web of trust which is represented explicitly by users as well as it is difficult to urge users to express their level of trustworthiness. We propose a fuzzy-based inference model for Web of trust using user behavior information in social network. According to the experiment result which is applied in Epinions.com, the proposed model show improved connectivity in resulting Web of trust as well as reduced prediction error of trustworthiness compared to existing computational model.

• Steel and Composite Structures
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• 제35권3호
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• pp.305-325
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• 2020

Beams of steel frame-tube structures (SFTSs) typically have span-to-depth ratios of less than five. This makes a flexural beam unsuitable for such an application because the plastic hinges at the beam-ends cannot be adequately developed. This leads to lower ductility and energy dissipation capacities of SFTSs. To address this, SFTSs with bolted web-connected replaceable shear links (SFTS-BWSLs) are proposed. In this structural system, a web-connected replaceable shear link with a back-to-back double channel section is placed at the mid-length of the deep beam to act as a ductile fuse. This allows energy from earthquakes to be dissipated through link shear deformation. SFTS and SFTS-BWSL buildings were examined in this study. Several sub-structures were selected from each designed building and finite element models were established to study their respective hysteretic performance. The seismic behavior of each designed building was observed through static and dynamic analyses. The results indicate that the SFTS-BWSL and SFTS have similar initial lateral stiffness and shear leg properties. The SFTS-BWSL had lower strength, but higher ductility and energy dissipation capacities. Compared to the SFTS, the SFTS-BWSL had lower interstory drift, base shear force, and story shear force during earthquakes. This design approach could concentrate plasticity on the shear link while maintaining the residual interstory drift at less than 0.5%. The SFTS-BWSL is a reliable resistant system that can be repaired by replacing shear links damaged due to earthquakes.

• 한국지진공학회논문집
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• 제3권3호
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• pp.55-62
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• 1999

철골조 및 합성구조의 건축물이 강한 지진하에서 효율적으로 거동하도록 유도하는 연구중의 하나로서 개구부를 가진 합성보의 이력거동을 조사하고 있다 실험적 연구와 비선형 FEM 해석 연구 모두가 그러한 합성보의 연성도를 입증하엿다 합성보 단부 즉 기둥 면에서 발생할 수 있는 취성파괴 이전에 직사각형 개구부의 모서리 주변에 있는 4개의 T형 단면에서 소성힌지를 형성하며 합성보 전체의 연성도를 유지하고 있다. 본연구는 직사각형 웨브 개구부를 가진 합성보의 강도와 초기강성도를 산정하는 약산식을 제시하였고 그결과를 실험 및 비선형 FEM 해석의 결과와 비교 분석하였다.

• Steel and Composite Structures
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• 제8권2호
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• pp.145-158
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• 2008

In slender sections there is a substantial post-buckling strength provided after the formation of local buckling waves. These waves happened due to normal stresses or shear stresses or both. In this study, a numerical investigation of the behavior of slender I-section beams in combined pure bending and shear has been described. The studied cases were assumed to be prevented from lateral torsional buckling. To achieve this aim, a finite element model that simulates the geometric and material nonlinear nature of the problem has been developed. Moreover, the initial geometric imperfections were included in the model. Different flange and web width-thickness ratios as well as web panel aspect ratios have been considered to draw complete set of interaction diagrams. Results reflect the interaction behavior between flange and web in resisting the combined action of moments and shear. In addition, the web panel aspect ratio will not significantly affect the combined ultimate shear-bending strength as well as the post local buckling strength gained by the section. Results are compared with that predicted by both the Eurocode 3 and the American Iron and Steel specifications, AISI-2001. Finally, an empirical interaction equation has been proposed.