• Computers and Concrete
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• 제19권1호
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• pp.7-17
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• 2017

In Chinese Design Codes, for super high-rise buildings with complex structural distribution, which are regarded as code-exceeding buildings, elasto-plastic time history analysis is needed to validate the requirement of "no collapse under rare earthquake". In this paper, a 117-story super high-rise building is discussed. It has a height of 597 m and a height-width ratio of 9.5, which have both exceeded the limitations stipulated by the Chinese Design Codes. Mega columns adopted in this structure have cross section area of about $45m^2$ at the bottom, which is infrequent in practical projects. NosaCAD and Perform-3D, both widely used in nonlinear analyses, were chosen in this study, with which two model were established and analyzed, respectively. Elasto-plastic time history analysis was conducted to look into its seismic behavior, emphasizing on the stress state and deformation abilities under intensive seismic excitation.From the comparisons on the results under rare earthquake obtained from NosaCAD and Perform-3D, the overall responses such as roof displacement, inter story drift, base shear and damage pattern of the whole structure from each software show agreement to an extent. Besides, the deformation of the structure is below the limitation of the Chinese Codes, the time sequence and distribution of damages on core tubes are reasonable, and can dissipate certain inputted energy, which indicates that the structure can meet the requirement of "no collapse under rare earthquake".

• 한국콘텐츠학회논문지
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• 제18권7호
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• pp.74-83
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• 2018

본 연구는 스토리텔링 광고에서 스토리유형에 따른 유명인 모델과 일반인 모델의 효과 차이를 분석하였다. 광고모델유형(유명인, 일반인)과 스토리유형(라이프체험형, 신화상징형)을 조작한 $2{\times}2$ 요인설계 실험이 진행되었다. 수도권에 거주하는 30-40대 여성 200명을 대상으로 온라인 조사를 수행하였다. 연구결과, 라이프체험형 광고의 경우, 광고태도, 브랜드태도, 구매의도 등 세 가지 종속변인 모두에 대해 일반인 모델이 유명인 모델보다 높은 광고효과를 보이는 것으로 나타났다. 신화상징형 광고의 경우, 광고태도에 대해서는 유명인 모델이 일반인 모델보다 높은 광고효과를 보이고 있었으나, 브랜드태도와 구매의도에 있어서는 모델 유형간 차이가 발견되지 않았다. 연구결과의 이론적 실무적 함의는 결론에서 논의되었다.

• Structural Engineering and Mechanics
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• 제13권4호
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• pp.369-385
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• 2002

Ductility capacity is comprehensively studied for steel moment-resisting frames. Local, story and global ductility are being considered. An appropriate measure of global ductility is suggested. A time domain nonlinear seismic response algorithm is used to evaluate several definitions of ductility. It is observed that for one-story structures, resembling a single degree of freedom (SDOF) system, all definitions of global ductility seem to give reasonable values. However, for complex structures it may give unreasonable values. It indicates that using SDOF systems to estimate the ductility capacity may be a very crude approximation. For multi degree of freedom (MDOF) systems some definitions may not be appropriate, even though they are used in the profession. Results also indicate that the structural global ductility of 4, commonly used for moment-resisting steel frames, cannot be justified based on this study. The ductility of MDOF structural systems and the corresponding equivalent SDOF systems is studied. The global ductility values are very different for the two representations. The ductility reduction factor $F_{\mu}$ is also estimated. For a given frame, the values of the $F_{\mu}$ parameter significantly vary from one earthquake to another, even though the maximum deformation in terms of the interstory displacement is roughly the same for all earthquakes. This is because the $F_{\mu}$ values depend on the amount of dissipated energy, which in turn depends on the plastic mechanism, formed in the frames as well as on the loading, unloading and reloading process at plastic hinges. Based on the results of this study, the Newmark and Hall procedure to relate the ductility reduction factor and the ductility parameter cannot be justified. The reason for this is that SDOF systems were used to model real frames in these studies. Higher mode effects were neglected and energy dissipation was not explicitly considered. In addition, it is not possible to observe the formation of a collapse mechanism in the equivalent SDOF systems. Therefore, the ductility parameter and the force reduction factor should be estimated by using the MDOF representation.

• Structural Engineering and Mechanics
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• 제51권2호
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• pp.277-297
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• 2014

Since the isolation bearings undergo large displacements in base-isolated structures, impact with adjacent structures is inevitable. Therefore, in this investigation, the effect of impact on seismic response of isolated structures mounted on double concave friction pendulum (DCFP) bearings subjected to near field ground motions is considered. A non-linear viscoelastic model of collision is used to simulate structural pounding more accurately. 2-, 4- and 8-story base-isolated buildings adjacent to fixed-base structures are modeled and the coupled differential equations of motion related to these isolated systems are solved in the MATLAB environment using the SIMULINK toolbox. The variation of seismic responses such as base shear, displacement in the isolation system and superstructure (top floor) is computed to study the impact condition. Also, the effects of variation of system parameters: isolation period, superstructure period, size of seismic gap between two structures, radius of curvature of the sliding surface and friction coefficient of isolator are contemplated in this study. It is concluded that the normalized base shear, bearing and top floor displacement increase due to impact with adjacent structure. When the distance between two structures decreases, the base shear and displacement increase comparing to no impact condition. Besides, the increase in friction coefficient difference also causes the normalized base shear and displacement in isolation system and superstructure increase in comparison with bi-linear hysteretic behavior of base isolation system. Totally, the comparison of results indicates that the changes in values of friction coefficient have more significant effects on 2-story building than 4- and 8-story buildings.

• 한국콘텐츠학회논문지
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• 제19권7호
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• pp.47-53
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• 2019

이 논문은 영화의 결말과 열린 결말에 관한 분석이다. 특히 열린 결말의 정의와 해석을 다루는 것이 이 연구의 핵심이다. '결말'에 대한 정의를 먼저 내리고, 데이비드 하워드와 로버트 맥키의 목표 추구모델로 결말을 '닫힌'과 '열린'으로 구분하는 작업을 진행했다. 연구 결과 창작자의 의도와 더불어 관객의 생각이 결말을 정의하는데 매우 큰 비중이 있음을 확인하게 되었다. 이야기는 창작자가 설계한 것이지만, 그것을 해석하는 것은 결국 관객의 몫이며, 관객은 자신이 가진 가치나 이야기에 대한 흥미에 따라 원하는 결말이 다를 수 있고 결국 결말의 정의 역시 결정할 수 있었다. 물론 열린 결말로 거론된 영화들을 포함하여, 대다수 영화가 닫힌 결말을 갖고 있는 것은 전통적 사실이며 앞으로 이런 이야기의 구조는 크게 변하지 않을 것이다. 그러나 창작자의 의도나 관객의 생각에 따라 닫힌 결말로 설계된 이야기도 열린 결말로 변모될 수 있으며, 열린 결말의 의도를 오히려 관객이 받아들이지 않을 수도 있다.

• Earthquakes and Structures
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• 제20권3호
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• pp.295-307
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• 2021

The gap provided between adjacent structures in the metropolitan cities is mostly narrow due to architectural and financial issues. Consequently, structural pounding occurs between adjacent structures during earthquakes. It causes damages, ranging from minor local to more severe ones, especially in the case of seismically isolated buildings, due to their higher displacements. However, due to the increased flexibility of isolated buildings, the problem could become more detrimental to such structures. The effect of the seismic pounding of moat walls on the response of buildings isolated by Triple Friction Pendulum Bearing (TFPB) is investigated in this paper. To this propose, two symmetric three-dimensional models, including single-story and five-story buildings, are modeled in Opensees. Nonlinear Time History Analyses (NTHA) are performed for seismic evaluation. Also, five different sizes with four different sets of friction coefficients are considered for base isolators to cover a whole range of base isolation systems with various geometry configurations and fundamental period. The results are investigated in terms of base shear, buildings' drift, and roof acceleration. Results indicated a profound effect of poundings against moat walls. In situations of potential pounding, in some cases, the influence of impact on seismic responses of multistory buildings was more remarkable.

• 창의정보문화연구
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• 제5권3호
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• pp.329-343
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• 2019

본 연구에서는 자폐성장애 학생들의 사회적 기술 향상을 위한 상황이야기 중재 콘텐츠를 담은 모바일 애플리케이션을 개발하고 평가하였다. 본 연구를 위해 자폐성장애 학생을 지도해 본 경험이 있는 교사 20명을 대상으로 요구조사를 실시하여 애플리케이션의 필요성을 확인하였고, 요구조사의 결과를 바탕으로 자폐성장애 학생의 특성과 요구를 고려한 모바일 애플리케이션을 개발하였다. 개발된 애플리케이션은 안드로이드 앱 스토어에 심사를 거쳐 등록하고, 현장 교사 10명에게 휴리스틱 사용성 평가를 진행하였다. 평가 결과 교육적 가치, 콘텐츠 구현 기술, 콘텐츠 정보 및 편의성 영역에서 모두 '매우 양호'에 가까운 결과를 얻었으며, 평가 결과에서 제시된 보완해야 할 사항들을 반영하여 애플리케이션을 완성하였다. 본 연구는 장애 학생의 사회적 기술 지도와 관련된 소프트웨어가 전무한 실정에서 관련 소프트웨어 개발 연구 활성화에 토대가 될 것으로 기대된다.

• Earthquakes and Structures
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• 제25권6호
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• pp.399-415
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• 2023

In this study, we investigate the use of a negative stiffness tuned inerter damper system to improve the performance of a base-isolated structure. The negative stiffness tuned inerter damper system consists of a tuned inerter damper connected in parallel with a negative stiffness element. To find the optimal parameters for the base-isolated structure with negative stiffness tuned inerter damper system, we develop an optimization method based on performance criteria. The objective of the optimization is to minimize the superstructure acceleration response ratio, while ensuring that the base displacement response ratio remains below a specified target value. We evaluate the proposed method by conducting numerical analyses on an eight-story building. The structure is modeled using both a simplified 3-degree-of-freedom system and a more detailed story-by-story shear-beam model. Lastly, a comparative analysis using time history analysis is performed to compare the performance of the base-isolated structure with negative stiffness tuned inerter damper system with that of the base-isolated structure and base-isolated structure with tuned inerter damper systems. The results obtained from the comparative analysis show that the negative stiffness tuned inerter damper system outperforms the tuned inerter damper system in reducing the dynamic seismic response of the base-isolated structure. Overall, this study demonstrates that the negative stiffness tuned inerter damper system can effectively enhance the performance of base-isolated structures, providing improved seismic response reduction compared to other systems.

• Smart Structures and Systems
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• 제29권5호
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• pp.729-746
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• 2022

In this paper, a nonlinear structural model updating methodology based on the Deep Belief Network (DBN) is proposed. Firstly, the instantaneous parameters of the vibration responses are obtained by the discrete analytical mode decomposition (DAMD) method and the Hilbert transform (HT). The instantaneous parameters are regarded as the independent variables, and the nonlinear model parameters are considered as the dependent variables. Then the DBN is utilized for approximating the nonlinear mapping relationship between them. At last, the instantaneous parameters of the measured vibration responses are fed into the well-trained DBN. Owing to the strong learning and generalization abilities of the DBN, the updated nonlinear model parameters can be directly estimated. Two nonlinear shear-type structure models under two types of excitation and various noise levels are adopted as numerical simulations to validate the effectiveness of the proposed approach. The nonlinear properties of the structure model are simulated via the hysteretic parameters of a Bouc-Wen model and a Giuffré-Menegotto-Pinto model, respectively. Besides, the proposed approach is verified by a three-story shear-type frame with a piezoelectric friction damper (PFD). Simulated and experimental results suggest that the nonlinear model updating approach has high computational efficiency and precision.

• 한국지진공학회논문집
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• 제2권4호
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• pp.191-197
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• 1998

This paper described the dynamic characteristics of 20-story apartment buildings from the results of full-scale measurements and analysis. The natural frequencies and mode shapes are quantified by measuring and analyzing ambient vibrations of the structure and compared with the results from dynamic analysis. Comparison with computed mode shapes and frequencies shows good agreement with the experimental results. It proved that it is important to estimate coupling beam and soil parameters through a comparison of the measured results with calculated results.