• Smart Structures and Systems
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• 제24권1호
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• pp.1-14
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• 2019

Transmission tower-line system is one of most critical lifeline systems to cities. However, it is found that the transmission tower-line system is prone to be damaged by earthquakes in past decades. To mitigate seismic demands, this study introduces a tuned-mass damper (TMD) using superelastic shape memory alloy (SMA) spring for the system. In addition, considering the dynamic characteristics of both tower-line system and SMA are affected by temperature change. Particular attention is paid on the effect of temperature variation on seismic behavior. In doing so, the SMA-TMD is installed into the system, and its properties are optimized through parametric analyses. The considered temperature range is from -40 to $40^{\circ}C$. The seismic control effect of using SMA-TMD is investigated under the considered temperatures. Interested seismic performance indices include peak displacement and peak acceleration at the tower top and the height-wise deformation. Parametric analyses on seismic intensity and frequency ratio were carried out as well. This study indicates that the nonlinear behavior of SMA-TMD is critical to the control effect, and proper tuning before application is advisable. Seismic demand mitigation is always achieved in this wide temperature range, and the control effect is increased at high temperatures.

• Structural Monitoring and Maintenance
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• 제9권3호
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• pp.271-287
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• 2022

This study investigates the bending behavior of a composite concrete slab roof with different methods of externally strengthing using steel plates and carbon fiber reinforced polymer (CFRP) strips. First, the concrete slab model which was reinforced with CFRP strips on the bottom surface of it is validated using experimental data, and then, using numerical modeling, 7 different models of square-shaped composite slab roofs are developed in ABAQUS software using the finite element modeling. Developed models include steel rebar reinforced concrete slab with variable thickness of CFRP and steel plates. Considering the control sample which has no external reinforcement, a set of 8 different reinforcement states has been investigated. Each of these 8 states is examined with 6 different uncertainties in terms of the properties of the materials in the construction of concrete slabs, which make 48 numerical models. In all models loading process is continued until complete failure occurs. The results from numerical investigations showed using the steel plates as an executive method for strengthening, the bending capacity of reinforced concrete slabs is increased in the ultimate bearing capacity of the slab by about 1.69 to 2.48 times. Also using CFRP strips, the increases in ultimate bearing capacity of the slab were about 1.61 to 2.36 times in different models with different material uncertainties.

• Smart Structures and Systems
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• 제32권1호
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• pp.49-59
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• 2023

A bridge transportation network supplies products from various source nodes to destination nodes through bridge structures in a target region. However, recent frequent earthquakes have caused damage to bridge structures, resulting in extreme direct damage to the target area as well as indirect damage to other lifeline structures. Therefore, in this study, a surrogate model-based comprehensive framework to estimate the seismic resilience of bridge transportation networks is proposed. For this purpose, total system travel time (TSTT) is introduced for accurate performance indicator of the bridge transportation network, and an artificial neural network (ANN)-based surrogate model is constructed to reduce traffic analysis time for high-dimensional TSTT computation. The proposed framework includes procedures for constructing an ANN-based surrogate model to accelerate network performance computation, as well as conventional procedures such as direct Monte Carlo simulation (MCS) calculation and bridge restoration calculation. To demonstrate the proposed framework, Pohang bridge transportation network is reconstructed based on geographic information system (GIS) data, and an ANN model is constructed with the damage states of the transportation network and TSTT using the representative earthquake epicenter in the target area. For obtaining the seismic resilience curve of the Pohang region, five epicenters are considered, with earthquake magnitudes 6.0 to 8.0, and the direct and indirect damages of the bridge transportation network are evaluated. Thus, it is concluded that the proposed surrogate model-based framework can efficiently evaluate the seismic resilience of a high-dimensional bridge transportation network, and also it can be used for decision-making to minimize damage.

• Geomechanics and Engineering
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• 제31권3호
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• pp.319-328
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• 2022

Ensuring the integrity of a country's infrastructure is necessary to protect surrounding communities in case of disaster. Embankment dam systems across the US are an essential component of infrastructure, referred to as lifeline structures. Embankment dams are crucial to the survival of life and if these structures were to fail, it is imperative that states be prepared. Southern California is particularly concerned with the stability of embankment dams due to the frequent seismic activity that occurs in the state. The purpose of this study was to create a numerical model of an existing embankment dam simulated under seismic loads using previously recorded data. The embankment dam that was studied in Los Angeles, California was outfitted with accelerometers provided by the California Strong Motion Instrumentation Program that have recorded strong motion data for decades and was processed by the Center for Engineering Strong Motion Data to be used in future engineering applications. The accelerometer data was then used to verify the numerical model that was created using finite element modeling software RS2. The results from this study showed Puddingstone Dam's simulated response was consistent with that experienced during previous earthquakes and therefore validated the predicted behavior from the numerical model. The study also identified areas of weakness and instability on the dam that posed the greatest risk for its failure. Following this study, the numerical model can now be used to predict the dam's response to future earthquakes, develop plans for its remediation, and for emergency response in case of disaster.

• 한국사회복지학
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• 제58권4호
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• pp.291-312
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• 2006

본 연구는 행동심리학의 견고한 이론적 기반을 가지고 북미에서 약물남용자에게 효과성이 실증적으로 입증된 접근방법인 인센티브치료를 국내 지역사회기관에서 두 명의 알코올남용클라이언트에게 실시하고 그 효과성을 알아보는 것을 목적으로 한 탐색적 조사이다. 이를 위해 ABA단일체계설계를 활용하여 총 12주간의 기초선 단계, 인센티브치료 개입단계, 개입철회단계동안 표적행동으로 클라이언트의 음주여부를 음주측정기로 측정하였다. 시행결과 음주사용의 감소가 인센티브치료 개입단계 중반 무렵부터 발생하였다. 개입철회단계에서는 한 사례의 경우 다시 음주가 시작된 반면, 또 한 사례에서는 단주가 유지되어 일관된 결과를 발견할 수 없었다. 하지만 인센티브치료는 알코올남용자의 단주에 대한 동기를 유발시켜 지속적인 심리사회적 상담 및 사회복지개입의 기회를 제공한다는 점에서 지역사회에서 실행가능성이 높은 방법임이 제시되었다.

• 디지털융복합연구
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• 제11권4호
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• pp.109-119
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• 2013

본 논문은 e-비즈니스에 따른 거래비용의 변화를 파악하고, 이를 바탕으로 한 적용분야로 에너지 및 환경 문제, 그리고 글로컬 전략에 대한 개념적인 측면을 경제학적 관점에서 살펴보았다. 먼저, 오프라인 거래와 온라인 거래 간에 발생하는 경제적 비용의 차이를 고려하여 두 채널간의 거래비용을 서로 다른 세 가지 경제학적 관점에서 비교함으로써 소비자와 판매자간에 발생하는 거래비용의 상충관계를 적시하였다. 둘째, 지속가능성의 관점에서 에너지 및 환경사업에 영향을 미치는 e-비즈니스의 역할을 파악하기 위해 물류시스템, 제품설계 프로세스, 그리고 에너지 절감에 대한 고려사항을 검토하였다. 이를 통해 e-비즈니스가 에너지 및 물류시스템의 효율성을 최적화하는 과정에서 저탄소 환경문제에 장단기적으로 다른 영향을 미칠 것으로 분석하였다. 마지막으로 글로벌 시대의 기회와 도전에 있어서 e-비즈니스에 의한 글로컬 전략을 네트워크 경제학의 관점에서 고찰하였다. 특히, e-비즈니스가 글로벌 시장으로 진출하는 지렛대로서의 역할을 최대화할 수 있도록 사업자간 네트워크의 통합, 사회문화적 환경을 고려한 지역화 및 현지화 전략, 그리고 표준화에 따른 세계적인 법적 기준의 주도적 설정 등이 중요한 글로벌 경영전략이 될 수 있다. 향후 e-비즈니스 성장모델은 거래비용의 관점에서 이러한 경제적 효과들의 상충관계를 조정할 수 있도록 지속가능한 형태로 진화되어야 할 것이다.

• 대한간호
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• 제28권3호
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• pp.83-93
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• 1989

This study analysed marital comflicts, related factors, and adjustments to those conflicts described by urban Korean women. The purpose was to discover directions for resolution that would enhance the helpfulness of volunteers or prfessionals working with women in counselling settings. The investigator interviewed 20 married women, all mothers and housewives living in Seoul, attending marriage encounter programs and the Lifeline telephone counselling service. An interview schedule using six open-ended questiona guided the data colleciton which took place between May 31 and December 29, 1988. Content analysis of the data revealed, in order of reported frequency, the following areas of conflict: relationships between husband wife, relationships with children, relationships between the wife and her mother-in-Law, unsatisfied sexual needs, the husband's extra marital relationships, lack of self actualization and finacial matters. Analysis of the data suggested the following factors were related to the conflicts: reasons for marriage, traditional views about marriage and divorce including to accept a marriage arranged by the parents, the husband's traditonal attitude toward the sex role of the wife, the husband's patriarchical authoritarianism, and his attitude toward the wife;s empolyment outside the home. The women thought these conflicts severely affected their relationships within the famaily, particularly with their children. Literature suggests links with such poor parent-child-family relationships and adolescent or young people's social problems. Volunteers or professionals working with married women in counselling situation need to be conscious of the possibility of these conflict during assessment, and direct their guidance toward such conflict resolution. The researcher makes several suggestions which include the need for the husband to give emotional supports to his wife, to recognize the worth of housework, to share the work of the home, to fine ways to enhance the wife's self-actualization and to ease dreary housework routines by prviding modern appliances.

• 성인간호학회지
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• 제12권4호
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• pp.497-506
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• 2000

The purpose of this phenomenological study was to explore and describe the experience of people with HIV/AIDS. Three men and three women with HIV/AIDS participated in the study. They were asked open-ended and descriptive questions in order for them to talk about their experience in their own terms. Interviews were audiotaped and transcribed to maintain data integrity and to reduce perceptual bias. The transcripts were analyzed by the Colaizzi method. Member checks from the participants were used to validate the emergent themes. Seven themes emerged from the analysis. 1. People with HIV/AIDS have a strong impact and emotional reaction when receiving positive HIV test results. 2. All people with HIV/AIDS attempt to conceal HIV infection because of fear of stigma or rejection. 3. After the initial brief traumatic reaction to HIV/AIDS diagnosis, all participants feel lonely because they had no one to express or share their own experiences. 4. People with HIV/AIDS reflect on their life, think about the death and dying process and they become depressed. 5. Most participants feel that the family members who know his/her diagnosis are a big source of support. 6. According to the normativeness of infection route of HIV, the degree of guilty feeling differs among participants. 7. Although all participants think medication is a lifeline, the adherence to medication is not maintained because of side effects, denial and concealment of HIV/AIDS. The results of this study may help nurses and other health care workers to implement more efficient nursing strategies for people with HIV/AIDS by more deeply understanding their experience.

• 한국도로학회논문집
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• 제5권2호
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• pp.25-35
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• 2003

원형지하매설관의 경우 관의 하단부의 다짐이 매우 어렵고, 또한 다짐효율이 떨어져서 지하매설물의 안정성을 저감시키고, 이로 인해 각종 파손이 발생하는 문제점을 가지고 있다. 이러한 문제점을 해결할 수 있는 하나의 대안으로 저강도 콘크리트 개념을 지반공학에 적용하여 만들어진 CLSM을 이용하는 것이다. 본 연구에서는 지금까지의 CLSM 실내실험결과를 이용하여 현장적용성 시험을 하기 위한 중간단계로서 베딩재, 뒤채움재, 관의 종류를 변화시킨 20가지 사례에 대한 PENTAGON 유한요소 프로그램을 이용하여 수치해석을 실시하였다. 수치해석을 실시한 결과 뒤채움재로 CLSM을 사용하는 경우에 토사나 일반모래를 사용한 경우보다 지표면 및 관의 침하를 현저히 감소시키는 것으로 해석되었다. 관의 연직변위를 놓고 볼 때 토사 뒤채움을 사용한 경우에 연성관의 변위량이 강성관의 2배 정도에 달했으나 CLSM으로 대체한 경우에는 오히려 토사 뒤채움에 강성관을 사용한 경우보다 변위가 줄어들었다. CLSM 뒤채움에 강성관을 사용한 경우도 유사하게 나타났고, CLSM이 구조적인 지지 역할을 확실히 함을 보여준다.

• 고문화
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• 57호
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• pp.157-194
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• 2001

태실이란 왕실에서 자손이 태어나면 의식과 절차를 거처 태를 묻은 시설을 말한다. 태는 태어난 아기의 생명선이며 근원이 된다고 하여 예로부터 소중하게 다루어졌다. 특히 왕실에서 아기가 태어나면 그 태를 소중하게 취급하여 길지를 골라 태실을 만들어 안태하였다. 태를 봉안한 최초의 문헌기록은 $\ulcorner$삼국사기$\lrcorner$로서 신라 때 김유신의 태를 묻었다고 한다. 신라이후 고려시대 왕실에서 태 봉안의식이 성립된후 조선시대까지 그 맥락이 이어진 오랜 전통을 가진 제도라 하겠다. 이런 태실이 울진지역에서 필자에 의해 1997. 12부터 2000. 7까지 약 2년7개월간이라는 조사기간을 통해 신래태실, 나곡태실, 화구태실과 절태봉 등 4곳이 확인되었다. 본 글에서는 이러한 관점을 바탕으로 각 태실의 주인공과 그 유물의 실체를 밝혀 보았다. 신래태실은 그 동안 행방조차 파악되지 않던 태지석, 태호, 조선통보의 유물을 모두 찾게 되었으며 조선 성종 17년(AD1486) 12월6일 오후9$\~$11시 사이에 태어나 다음해 4월7일 오전11$\~$오후1시 사이에 장태한 성종의 아들인 견석왕자의 태실로 밝혀졌다. 나곡태실은 도굴되었던 태지석의 명문도 밝혀졌으며 이 태실은 조선 광해군 11년(AD1619) 5월23일 오후9$\~$11시 사이에 태어나서 그 해 11월4일 오전9$\~$11시 사이에 장태한 광해군의 딸 태실이다. 화구태실은 신라시대 왕자의 태실로 구전되어 오는데, 풍수지리적 여건으로 보아 태실임이 분명하나 더 이상의 태실에 대한 단서를 찾을 수가 없었다. 절태봉도 태실로 추정된다. 지금까지 태실에 대한 연구가 조선왕실의 장태처리에 관한 귀중한 연구임에도 불구하고 거의 진행되고 있지 않은 실정이다. 이러한 시점에서 울진지역에서 발견된 태실들은 태실제도를 규명하는데 귀중한 정보를 제공해 줄 것으로 기대된다.