• Earthquakes and Structures
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• 제7권4호
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• pp.527-552
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• 2014

The development of modern concrete technology makes it much easier to produce high-strength concrete (HSC) or ultra-high-strength concrete (UHSC) with high workability. However, the application of this concrete is limited in practical construction of traditional reinforced concrete (RC) structures due to low-ductility performance. To further push up the limit of the design concrete strength, concrete-filled-steel-tube (CFST) columns have been recommended considering its superior strength and ductility performance. However, the beneficial composite action cannot be fully developed at early elastic stage as steel dilates more than concrete and thereby reducing the elastic strength and stiffness of the CFST columns. To resolve this problem, external confinement in the form of steel rings is proposed in this study to restrict the lateral dilation of concrete and steel. In this paper, a total of 29 high-strength CFST (HSCFST) columns of various dimensions cast with concrete strength of 75 to 120 MPa concrete and installed with external steel rings were tested under uni-axial compression. From the results, it can be concluded that the proposed ring installation can further improve both strength and ductility of HSCFST columns by restricting the column dilation. Lastly, an analytical model calculating the uni-axial strength of ring-confined HSCFST columns is proposed and verified based on the Von-Mises and Mohr-Coulomb failure criteria for steel tube and in-filled concrete, respectively.

• 대한간호
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• 제34권2호
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• pp.66-76
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• 1995

This study was done to identify burnout factors and coping methods surveyed upon 59 out-patients who have continuous peritoneal dialysis. Raw data was collected after being filled the questionnaire by subjects or directly interviewing at the peritoneal dialysis room of the K hospital. Taegu. Then. data was classified and analyzed according to categories of questions and revealed facts. The following results are obtained: The average age of subjects is 43.8 years old and the average duration of continuous peritoneal dialysis is 16.9 months. The reasons of choosing continuous peritoneal dialysis are 61. 0% by recommendation of doctor and nurse ranked as the first, 32. 2% by patient own decision ranked as the second. The 57.6% of subjects were experienced complications related to continuous peritoneal dialysis. The major psychosocial burnout factors because of the dialysis are confinement, wasting time, change in responsibility and role as a member of family, worriment for infection, interference in job: and the major physiological burnout factors are fatigue and weakness. Among the main coping methods, the problem-oriented coping methods are "accept the given situation itself, "actively try to change the situation", "try to maintain some controls over the situation", and the affective-oriented coping method are "give up and accept as fate", "pray", "ask comfort or help from family and friends", "sleep", "cry". Conclusively, it can be said that effective nursing intervention is needed to prevent continuous peritoneal dialysis burnout.

• Structural Engineering and Mechanics
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• 제39권4호
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• pp.559-578
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• 2011

In regions of high seismic risk, high-strength concrete (HSC) columns of tall buildings are designed to be fully ductile during earthquake attack by providing substantial amount of confining steel within the critical region. However. in areas of low to moderate seismic risk, the same provision of confining steel is too conservative because of the reduced seismic demand. More critically, it causes problematic steel congestion in the beam-column joints and column critical region. This will eventually affect the quality of concrete placing owing to blockage. To relieve the problem, the confining steel in the critical region of HSC columns located in low to moderate seismicity regions can be suitably reduced, while maintaining a limited ductility level. Despite the advantage, there are still no guidelines developed for designing limited ductility HSC columns. In this paper, a formula for designing limited ductility HSC columns is presented. The validity of the formula was verified by testing half-scale HSC columns subjected to combined high-axial load and flexure, in which the confining steel was provided as per the proposed formula. From the test results, it is evident that the curvature ductility factors obtained for all these columns were about 10, which is the generally accepted level of limited ductility.

• 한국방재학회 논문집
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• 제7권3호
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• pp.1-7
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• 2007

중공 RC 기둥은 중실 RC 기둥에 비해 자중의 감소 및 재료 절감에 대한 장점을 가진다. 그러나 중공 RC 기둥은 안쪽면의 취성파괴로 인하여 낮은 연성 거동을 할 가능성이 있다. 이러한 문제점을 해결하기 위해 중공 부재 내의 콘크리트 3축 구속 상태로 존재하게 하는 강관으로 보강된 중공 RC 기둥이 개발되었으며, 본 연구에서는 강관으로 보강된 중공 RC 기둥의 중공비를 $0.50{\sim}0.85$까지 변화 시켜 중공비에 따른 작용하중에 대한 안전율, 연성도, 재료비, 교각 총 중량에 대한 거동 특성을 파악하였다.

• Clinical and Experimental Pediatrics
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• 제63권12호
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• pp.477-482
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• 2020

The childhood obesity pandemic has emerged as an important public health problem in many countries. Obese children are likely to become obese adults, and adult obesity is associated with an increased risk of morbidity. Therefore, controlling the childhood obesity epidemic has become a top public health priority worldwide. The current coronavirus disease 2019 (COVID-19) pandemic may significantly impede this important mission and constitute an unprecedented tragedy in the global battle against childhood obesity. This manuscript presents evidence that the COVID-19 pandemic will aggravate the childhood obesity epidemic and lead to significant weight gain in school children by creating an unprecedented obesogenic environment. Within the last few months, many countries took uncompromising measures in response to the COVID-19 pandemic, including school closures and quarantine. While these steps are often necessary to ensure infection control, they may have a significant negative effect on children's mental and physical health. Physical, nutritional, and psychosocial factors that promote obesity in children during this special situation complementarily contribute to an unprecedented obesogenic environment. Large-scale quarantine and home confinement will impose new and unfamiliar stressors on children, thereby worsening the childhood obesity epidemic. Most importantly, adverse childhood events resulting from a predicted increase in domestic violence within the next few months will significantly contribute to this concern. The scenario presented in this review is of paramount public health importance and must be considered during future pandemic planning. Involved stakeholders, including governments, schools, and families, must make all possible efforts to minimize the impact of the COVID-19 epidemic on childhood obesity.

• Geomechanics and Engineering
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• 제30권4호
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• pp.363-372
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• 2022

One of the most frequent issues in tunnel excavation is the collapse of rock blocks and the dropping of rock fragments from the tunnel face. The tunnel face can be reinforced using a number of techniques. One of the most popular and affordable solutions is the use of face longitudinal dowels, which has benefits including high strength, flexibility, and ease of cutting. In order to examine the reinforced face, this work shows the longitudinal deformation profile and ground response curve for a tunnel face. This approach is based on assumptions made during the analysis phase of problem solving. By knowing the tunnel face response and dowel behavior, the interaction of two elements can be solved. The rock element equation derived from the rock bolt method is combined with the dowel differential equation to solve the reinforced ground response curve (GRC). With a straightforward and accurate analytical equation, the new differential equation produces the reinforced displacement of the tunnel face at each stage of excavation. With simple equations and a less involved computational process, this approach offers quick and accurate solutions. The FLAC3D simulation has been compared with the suggested analytical approach. A logical error is apparent from the discrepancies between the two solutions. Each component of the equation's effect has also been described.

• Nuclear Engineering and Technology
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• 제55권6호
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• pp.2172-2194
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• 2023

A variational nodal method (VNM) with unstructured-mesh is presented for solving steady-state and dynamic neutron diffusion equations. Orthogonal polynomials are employed for spatial discretization, and the stiffness confinement method (SCM) is implemented for temporal discretization. Coordinate transformation relations are derived to map unstructured triangular nodes to a standard node. Methods for constructing triangular prism space trial functions and identifying unique nodes are elaborated. Additionally, the partitioned matrix (PM) and generalized partitioned matrix (GPM) methods are proposed to accelerate the within-group and power iterations. Neutron diffusion problems with different fuel assembly geometries validate the method. With less than 5 pcm eigenvalue (k_eff) error and 1% relative power error, the accuracy is comparable to reference methods. In addition, a test case based on the kilowatt heat pipe reactor, KRUSTY, is created, simulated, and evaluated to illustrate the method's precision and geometrical flexibility. The Dodds problem with a step transient perturbation proves that the SCM allows for sufficiently accurate power predictions even with a large time-step of approximately 0.1 s. In addition, combining the PM and GPM results in a speedup ratio of 2-3.

• 미술이론과 현장
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• 제8호
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• pp.123-144
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• 2009

The history of art during the first half of the last decade was founded the discussion with highly impressive and confident. The art might establish its unique area based on self recognition at that era. The self-confidence of modern art may be possible on enlightenment, which is the firm relationship for knowledge and reality. However the faith of modernism which shows rational tendency, objective, and the existence of universal knowledge has been drastically doubted and criticized thereafter. A internal ideological system which had leaded the modern art was exhausted. Postmodernism revolved to the dramatic openness leaning against the deoedipalizational confession. According to the dissipation of the vitality of modern art postmodern art has been evolved and then various phenomena which follow the trends has been emerged. The avant-garde and resisteive attribute of modern art was diluted fast due to the influx of popular culture. As time goes it can be attracted by spectacle taste than metaphysical peculiarity. It has to inevitably justified the drift of light and quick themes, contents, and images. Such as these phenomena realistically shows fact that postmodern art had been failed to open a new chapter of consilience which intermediates beauty and usual communication to overcome the solipsism of modernism. A trial to pursuit the opened esthetics conceived more 'heroic' 'Star-Subject' than before by dismantling the modern 'Hero-Subject'. Postmodernism has been recorded as a regression of art, which is the technology of profound spirit that mitigates antagonism and confrontation and mediates mutual encountering of human being. Prevailing of postmodern freedom had been accompanied by popularity, osetentation consumption, marketing, gambling level exitement, mixtures of desires with price fluctuations. We witness 'self-confinement' and 'lasting absence of exit' phenomena in postmodernism ideology and practice. We have to deal postmodernism as an 'ideology which closes the discussion for the future' in the context of 'absence of way' at this point. We are going to investigate how postmodern ideology and practice takes part in the prospection beyond thereafter through discussion. We also pay attention to the 'absence of prospection' as a internal problem in itself nevertheless mention the three merge points such as tradition or memory, earthy thought, the self who confrontation others as the clue of prospecting thought which is allowing coming over postmodern absence.

• 한국방재학회 논문집
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• 제10권4호
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• pp.17-24
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• 2010

중공 RC 교각은 중실 RC 교각에 비해 자중의 감소 및 재료 절감에 대한 장점을 가진다. 그러나 중공 RC 교각은 안쪽면의 취성파괴로 인하여 낮은 연성 거동을 할 가능성이 있다. 이러한 문제점을 해결하기 위해 중공 부재 내의 콘크리트 3축 구속 상태로 존재하게 하는 내부 구속 중공 RC 교각이 개발되었다. 본 연구에서는 내부 구속 중공 RC 교각의 매개변수(중공비, 내부강관두께, 횡방향 철근 간격, 종방향 철근 개수, 콘크리트 강도)변화에 따른 안전율, 연성도, 재료비 및 교각 총 중량에 대한 거동 특성을 파악하였다. 매개변수 변화에 따른 내부 구속 RC 교각의 거동 특성 결과 내부 강관 두께는 최소한의 내부강관 두께를 적용하는 것이 효과 적인 것으로 파악되었다.

• 한국사회복지학
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• 제63권2호
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• pp.291-317
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• 2011

본 연구는 가정폭력과 음주문제의 동시발생 현상과 그 피해의 심각화 및 만성화에 주목하여 음주문제를 가진 가정폭력배우자로 인해 피해를 당한 여성(이하: 음주폭력피해여성)의 경험을 이해하는 데 목적을 두었다. 이를 위해 10명의 음주폭력피해여성을 대상으로 심층 인터뷰한 후, Giorgi의 현상학적 연구방법을 활용하여 결과를 도출하였다. 연구 결과, 시간성과 관계성을 고려하여 혼전 음주폭력 몰이해단계, 음주폭력 피해와 대처단계, 음주폭력 휴지기단계로 구분할 수 있었다. 혼전 음주폭력 몰이해 단계에서는 상위구성요소로서 '음주폭력문제를 간과함'이 나타났다. 음주폭력 피해와 대처단계에서는 '음주폭력의 악순환에 갇힘'과 '지역사회에서 음주폭력을 다룸'이 도출되었다. 마지막으로 음주폭력 휴지기 단계에서는 '관계 재정립'의 의미가 나타났다. 이와 같은 연구결과에 근거하여 실천적, 정책적 함의를 제안하였다.