• 한국지진공학회논문집
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• 제20권2호
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• pp.103-112
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• 2016

Resonance occurrence conditions are explored by performing dynamic interaction analysis of arch bridge and KTX trains. The target bridge is a 3D tied-arch bridge having span length of 120m. KTX trains consist of two power carriages, two power and passenger carriages and sixteen passenger carriages. When KTX trains run on the target bridge with the uniform speed of 100 to 500km/h, the dynamic responses of the bridge induced by moving trains are obtained from railway arch bridge-train interaction analysis. Two resonance conditions are presented and whether the resonance phenomena occur or not at the suspicious resonance velocities is rigorously investigated through bridge deflections and accelerations and their FFT analysis.

• Structural Engineering and Mechanics
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• 제39권5호
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• pp.683-701
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• 2011

In this study, inelastic displacement ratios and ductility demands are investigated for SDOF systems with period range of 0.1-3.0 s. with elastoplastic behavior considering soil structure interaction. Earthquake motions recorded on different site conditions such as rock, stiff soil, soft soil and very soft soil are used in analyses. Soil structure interacting systems are modeled with effective period, effective damping and effective ductility values differing from fixed-base case. For inelastic time history analyses, Newmark method for step by step time integration was adapted in an in-house computer program. Results are compared with those calculated for fixed-base case. A new equation is proposed for inelastic displacement ratio of interacting system ($\tilde{C}_R$) as a function of structural period of interacting system ($\tilde{T}$), strength reduction factor (R) and period lengthening ratio ($\tilde{T}/T$). The proposed equation for $\tilde{C}_R$ which takes the soil-structure interaction into account should be useful in estimating the inelastic deformation of existing structures with known lateral strength.

• Structural Engineering and Mechanics
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• 제41권3호
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• pp.365-378
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• 2012

In this study, strength reduction factors are investigated for SDOF systems with period range of 0.1-3.0 s with elastoplastic behavior considering soil structure interaction for 64 different earthquake motions recorded on different site conditions such as rock, stiff soil, soft soil and very soft soil. Soil structure interacting systems are modeled and analyzed with effective period, effective damping and effective ductility values differing from fixed-base case. For inelastic time history analyses, Newmark method for step by step time integration was adapted in an in-house computer program. Results are compared with those calculated for fixed-base case. A new equation is proposed for strength reduction factor of interacting system as a function of structural period of system (T), ductility ratio (${\mu}$) and period lengthening ratio (T/T). It is concluded that soil structure interaction reduces the strength reduction factors for soft soils, therefore, using the fixed-base strength reduction factors for interacting systems lead to non-conservative design forces.

• 한국과학교육학회지
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• 제32권7호
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• pp.1251-1268
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• 2012

이 연구는 자연사 전시관에서 중학생들의 또래간 자유 관람 시 형성되는 전시물을 매개로 한 상호작용적 학습 과정의 사례를 조사하였다. 연구 자료로 관람객들의 상호작용이 활발했던 5건의 관람 사례를 선정하였다. 각 관람 사례에서 대화의 흐름에 근거한 관람객의 의미 구성 과정 및 전시물의 특성에 따른 관람 대화의 특징을 이해하기 위하여 관람 대화의 레지스터 분석 및 상호작용 양상 분석을 수행하였다. 연구결과는 다음과 같다. 전시물이 제공하는 정보는 관람객의 대화에 주제부로 반영되고, 관람객들은 주제부에 대한 정보를 설명부에 제시하여 서로 교환함으로써 전시물에 대한 주체적인 의미를 구성하였다. 한편, 전시 패널에 의문형의 문장을 사용하여 관람객의 논증을 유도하거나, 유사한 전시물들이 함께 제시되어 관람객에게 전시물 간의 비교를 유발하는 방식으로 관람객들의 의미 형성을 촉진하였다. 전시물을 매개로 한 관람객 간의 상호작용 양상의 특징을 보면, 관람객들의 의미 구성 과정에서 전시물에 대한 관람객의 의견뿐만 아니라 전시물이 가진 '정보' 자체도 의미를 구성하기 위한 심층인지적인 사회적 상호작용의 요소로 빈번하게 사용되어 관람 대화에서 정보의 구조가 상호작용 양상에 중요함을 알 수 있었다. 연구결과를 바탕으로 자연사 전시관에서 관람객의 협력적인 과학 학습을 발전시키기 위해서 관람객들이 전시물의 정보를 선택하여 관람 담화로 구성하는 양상을 자세히 이해하는 것이 중요함을 논의하였다.

• 예술인문사회 융합 멀티미디어 논문지
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• 제7권9호
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• pp.509-518
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• 2017

본 연구는 국내 거주 중국동포 여성 단체장에 대한 생애사 연구로 연구주체의 생애사 재구성 작업을 통해 한국사회와의 긍정적인 상호작용인 인정투쟁의 경험을 살펴보고자 했다. 연구는 내러티브-생애사 분석 방법으로 진행되었다. 생애사 자료는 심층 인터뷰을 통해 수집했다. 연구결과 생애사 연구주체의 생애는 끊임없는 도전의 결과로 한국을 기회의 땅으로 생각하고 한국으로 자발적으로 이주를 하였다. 그는 한국에서 긍정적인 적응전략을 활용하여 인정을 획득하기 위한 치열한 삶으로 분석할 수 있다. 즉 인정투쟁이라는 긍정적인 상호작용을 통하여 주류사회와 협상하고, 긍정적인 경험들을 통하여 자신의 정체성을 확립해 나갔다. 또, 단체활동을 통하여 개인뿐 만 아니라 동포사회 전반의 권리수호와 이미지 향상을 도모하며 주류사회와 융합되기 위해 끊임없이 노력하였다. 이러한 생애사 재구성을 통하여 중국동포 단체장의 생활 실상에 대하여 이해할 수 있고, 그들이 한국사회에서 받고 싶은 인정의 모습들에 대하여 알 수 있다. 따라서 이러한 개별적인 생애사 재구성을 통하여 사회복지 실천에 함의하는 점도 제언하였다.

• Earthquakes and Structures
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• 제5권6호
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• pp.679-702
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• 2013

During an earthquake, soils filter and send out the shaking to the building and simultaneously it has the role of bearing the building vibrations and transmitting them back to the ground. In other words, the ground and the building interact with each other. Hence, soil-structure interaction (SSI) is a key parameter that affects the performance of buildings during the earthquakes and is worth to be taken into consideration. Columns are one of the most crucial elements in RC buildings that play an important role in stability of the building and must be able to dissipate energy under seismic loads. Recent earthquakes showed that formation of plastic hinges in columns is still possible as a result of strong ground motion, despite the application of strong column-weak beam concept, as recommended by various design codes. Energy is dissipated through the plastic deformation of specific zones at the end of a member without affecting the rest of the structure. The formation of a plastic hinge in an RC column in regions that experience inelastic actions depends on the column details as well as soil-structure interaction (SSI). In this paper, 854 different scenarios have been analyzed by inelastic time-history analyses to predict the nonlinear behavior of RC columns considering soil-structure interaction (SSI). The effects of axial load, height over depth ratio, main period of soil and structure as well as different characteristics of earthquakes, are evaluated analytically by finite element methods and the results are compared with corresponding experimental data. Findings from this study provide a simple expression to estimate plastic hinge length of RC columns including soil-structure interaction.

• 대한예방한의학회지
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• 제17권1호
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• pp.1-11
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• 2013

Objectives : The aim of this research is to produce information by gathering up the data on the interaction between medicinal herbs which lie scattered in oriental medical books, and to provide people with easy access to the information by visualizing it. Methods : For this purpose, this study established the fundamental data by organizing the patterns of interaction into some kinds after selecting a part of Bonchogangmok(本草綱目) and extracting its text. In addition, in an effort to visualize the data, the study converted the data into 'net' file and visualized the interaction between medicinal herbs on Pajek. The visualization was done targeting a total of three patterns, such as 1 medicinal herb, 2 medicinal herbs, and 1 prescription. With the data on 'Chinese Lacquer(乾漆)' for 1 medicinal herb, data on 'Licorice(甘草)' and 'Chinese Lacquer(乾漆)' for 2 medicinal herbs, and data on 'Iijin-tang(二陳湯)' for prescription, the research conducted the analysis of the network using 'Kamada-Kawaii Algorithm' on Pajek. Results : As a result of the analysis, it was possible to see the meanings at a single glance as the scattered and fractional meanings were integrated with focus on medicinal herbs, but the increasing number of analyzed medicinal herbs tended to more and more complicate their relationships, thus, requiring additional work like filtering. Conclusions : Such results are fairly applicable in on-line database, and it is judged that if further research expands its scope to include systematic classification of medicinal herbs or cover other medical books than Bonchogangmok, it will create more objective, abundant information.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회B
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• pp.2506-2511
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• 2007

The coupled simulation is performed to find out the interaction of arc plasmas with surrounding materials in a thermal puffer plasma chamber. In order to be more realistic, PTFE nozzle ablation and Cu electrode evaporation, which are caused by high temperature of arc plasmas, are considered together. Pressure rise and temperature inside the chamber generated during the whole arcing history are investigated with the applied currents. It is very important to define how thermal flow and mass transfer are processing between the arc plasma and surrounding materials for further understanding complex physics inside the chamber. It is concluded that the result might be very useful to understand the mechanism happened inside and to design thermal puffer plasma chambers, but further experimental studies are required to verify the results for the more practical applications.

• Earthquakes and Structures
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• 제10권6호
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• pp.1347-1367
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• 2016

The purpose of this work is to investigate the seismic behavior of St. Titus Church in Heraklion, Crete, Greece as well as the need of its seismic retrofitting. A numerical model of the Church is constructed using shell finite elements and it is then seismically examined using response spectrum and linear time-history analyses. Effects of soil-structure interaction have been also taken into account. The Church without retrofit is expected to exhibit extensive tensile failures and many compressive ones. Aiming to maintain the architectural character of the structure as well as to increase its seismic resistance, a retrofitting procedure involving injection of cement grout in conjunction with reinforced concrete jacketing to the internal side of the masonry walls is proposed. A numerical implementation of the proposed seismic retrofitting is performed and its effect is evaluated by response spectrum and linear time-history analyses. From the results of these analyses, it is shown that compressive failures are eliminated while only few tensile failures of local character take place.

• Structural Engineering and Mechanics
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• 제17권3_4호
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• pp.573-591
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• 2004

A hybrid control system is presented for seismic-resistant building structures with and without soil-structure interaction (SSI). The hybrid control is a damper-actuator-bracing control system composed of passive and active controllers. An intelligent algorithm is developed for the hybrid system, in which the passive damper is designed for minor and moderate earthquakes and the active control is designed to activate when the structural response is greater than a given threshold quantity. Thus, the external energy for active controller can be optimally utilized. In the control of a multistory building, the controller placement is determined by evaluating the optimal location index (OLI) calculated from six earthquake sources. In the study, the soil-structure interaction is considered both in frequency domain and time domain analyses. It is found that the interaction can significantly affect the control effectiveness. In the hybrid control algorithm with intelligent strategy, the working stages of passive and active controllers can be different for a building with and without considering SSI. Thus SSI is essential to be included in predicting the response history of a controlled structure.