• 한국지진공학회논문집
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• 제10권5호
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• pp.85-97
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• 2006

성능보장설계는 교각이 완전한 소성회전성능을 발휘할 때까지 다른 구조요소들과 교각 자체가 취성파괴 되지 않도록 설계하여 교량 전체 시스템의 연성파괴를 보장하기 위한 것으로서, 현행 도로교설계기준에는 명시적으로 규정되어 있지 않으나 대부분의 외국 교량내진설계기준에 채택되어 있다. 성능보장설계에서는 철근콘크리트 교각의 휨 초과강도를 구하고 이를 변환한 전단력을 교각, 기초, 말뚝에 작용하는 횡하중 설계전단력으로 결정하여 교각의 전단설계, 기초설계, 말뚝설계를 수행하도록 규정한다. 이 때 교각의 최대 소성모멘트를 결정하는 방법은 설계기준별로 각기 다른데, 이는 각 국의 재료 시공환경이 다르기 때문이다. 본 연구에서는 국내에서 사용하는 철근의 인장강도 측정치 3,407개와 콘크리트 압축강도 측정치 5,405개의 분석을 통하여 재료 초과강도계수를 제안하였고, 이를 적용하여 휨 초과강도를 결정하는 방법을 제시하였으며, 1,500개의 교각단면에 대한 모멘트-곡률 해석을 수행한 후 통계분석을 통하여 우리나라 실정에 적합한 초과강도계수를 제안하였다.

• 한국지반공학회논문집
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• 제19권5호
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• pp.223-232
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• 2003

본 연구에서는 DSC를 이용한 구성방정식을 이용하여 토목섬유 사이의 접촉전단 응력과 변위와의 관계를 모델링하였다. DSC 모델은 두 개의 기준 상태, 즉 상대적으로 손상되지 않은 RI 상태와 완전히 파괴된 FA 상태와 한가지의 교란 함수로 구성된다. 본 모델은 통합된 모델로서, RI 상태를 탄성-완전 소성 모델, 계층적 단일 항복곡면 (HiSS) 모델 등 다양한 모델을 이용하여 모사할 수 있다. 한편 본 모델은 탄성과 소성 변위를 동시에 고려할 수 있다는 장점을 가지고 있다. 4가지의 대형 직접전단 시험으로부터 측정된 자료와 측정자료로부터 도출된 모델 변수를 이용하여 재해석한 결과를 서로 비교하여, 둘 사이의 비교 결과가 상당히 일치함을 발견하였으며, 특히 표면이 매끄러운 지오멤브레인의 접촉면에서는 매우 상관관계를 보였다. 비록 표면이 거친 지오멤브레인이 포함된 접촉면에서는 예측 최대 전단강도가 실험결과와 약간의 차이를 보이기는 하였지만, 전체적으로 본 모델이 최대 전단응력이 나타나는 변위점과 대변형에서의 전단강도를 상당히 정확히 예측하였으며, 이를 통해 본 모델이 변형율 연화 현상을 보이는 접촉면 전단거동의 모델링에 유용함을 확인하였다.

• 대한두개안면성형외과학회지
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• 제14권1호
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• pp.1-10
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• 2013

Background: Recently, substances from seaweeds have been widely used in hair growth solutions, and have been proven to be effective. Seaweeds have been documented to possess hair growth activity; however, no report on the effect of seaweed on hair regeneration has been issued to date. In this study, we investigated which exact substance of hair tonic made by JW-bio and our institute shows effects on hair growth by studying the mechanisms of candidate substances. Methods: The study was conducted to investigate the hair restoring effect of domestic natural substances; we categorized the candidate substances as seaweed, cereal, and herbal medicine. Five experimental groups were included in the study as follows: a saline group, a 50% ethanol group, seaweed group, a cereal group, and a herbal medicine group. Results: Three extracts (seaweed, cereal, and herbal medicine) were administered to C57BL/6 mice for two weeks after depilation. Depilated areas were found to be completely covered with fully grown hair, and the hair re-growth score was highest in the seaweed group. Using a hair analysis system, hair characteristics were measured in all groups on days 10 and 14 after depilation. The width and length of hair follicles were largest in the seaweed group. Groups treated with seaweed showed significantly increased gene expression of insulin-like growth factor-1. Groups treated with all the three extracts showed decreased expression of transforming growth factor-${\beta}1$. Conclusion: Findings from our study suggest that seaweeds possess hair-growth effects and may be useful for the treatment of alopecia in the future.

• 복식
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• 제29권
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• pp.23-38
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• 1996

The purpose of this study was to analyze the characteristics of the Minimal Art represented in the second half 20th century fashion. All the mode of dress worn this century have developed from the stimulus of a chang-ing society fired by new discoveries and a zest for the new and different. It would appear that even more dramatic changes will soon occur in our clothing styles the effects of which will be farreaching. Many of today's styles intended to dress our psyche rather than our bodies and this if fully understood by the new designers whose influ-ence will become increasingly more potent as we approach the new century. The highly developed material civilization resulted in human alienations environmental distruption, l By this fact human being of the 20th century was to overcome social com-plexity. Accordingly their search for simplicity was interested in the 60's style. Especially the formativeness of the 60s style was repre-sented in the second half 20th century fashion. In this paper it was focused that how the characteristics of the Minimal Art was expressed in the second half 20th century fashion. minimalism was a quest for basic elements repesenting the fundamental esthetic values of art. without regard to issues of content. At its most extreme it reduced art not ot an eter-nal essence but to an arid simplicity. "Primary Structure" the most suitable name suggested for this type conveys its two salient characteristics : extreme simplicity of shapes and a kinship with architecture. minimalist works are charcterized by huge dimensions coldness and absolute aesthetic neutrality. minimalist artists ambition is to de-fine through the most rudimentary materials such as plywood galvanized iron aluminum plastic and wood a new order of the space. The environment is just as important as the object itself. Similary the use of new tough materials. such as vinyl metal and plastic at late half of the 20th century fashion related to the formativeness of the Minimal Art. And the style of 20th fashion was holded the internal meanings in common the formativeness of the Minimal Aet thorough the various texture pat-tern silhouette etc.uette etc.

• 대한기계학회논문집
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• 제9권2호
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• pp.140-149
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• 1985

본 연구는 오오스테나이트계 STS 316 스테인레스강에 대하여 온도 550.deg. C의 대 기중에서, 변형율제어에 의한 인장-압축에 크리이프 유지시간을 갖는 고온저사이클 피 로시험을 하여 변형율폭 및 크리이프 유지시간이 피로수명에 미치는 영향과 파단면을 주사형 전자현미경으로 관찰하여 크리이프-피로 상호작용이 피로파단면에 미치는 크리 이프 효과를 실험 고찰하였다.

• Archives of Reconstructive Microsurgery
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• 제19권1호
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• pp.46-49
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• 2010

Purpose: It has been reported that the ear perfusion can maintain by a very small pedicle because the ear has good vascularized system. Replantation of an amputated ear with vascular anastmosis, has been reported before and offers the succeessful reconstructive results. But, in this paper we report a case of complete nonmicrosurgical salvage of a nearly amputated ear based on 7 mm-wide small skin pedicle with adjunctive therapies. Methods: A 49-year-old man was referred with a nearly complete detachment of left ear. The blood supply to the ear was maintained exclusively on 7 mm-wide small skin pedicle in the lobule. After we identified the fresh bleeding at the distal margin of the detached ear, we performed the primary repair. At the end of the procedure, the areas of the concha bowl and helical root appeared to be congested. So the immediate postoperative treatment for improving the tissue survival was done with Lipo-Prostaglandin E1 (Eglandin$^{(R)}$) injection, leech apply and antibiotics medications. Results: Assessment of the replanted ear on postoperative day 14 revealed a nearly viable auricle including the helical root. The ear appeared to be entirely healed, with excellent projection and fully restored normal elasticity. Conclusion: We found the complete salvage of a nearly amputated ear based on 7 mm-wide small skin pedicle with adjunctive therapies including Lipo-Prostaglandin E1 (Eglandin$^{(R)}$) injection, leech apply and antibiotics without microsurgery.

• Computers and Concrete
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• 제1권3호
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• pp.325-354
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• 2004

Slabs in buildings and bridge decks, which are restrained against lateral displacements at the edges, have ultimate strengths far in excess of those predicted by analytical methods based on yield line theory. The increase in strength has been attributed to membrane action, which is due to the in-plane forces developed at the supports. The benefits of compressive membrane action are usually not taken into account in currently available design methods developed based on plastic flow theories assuming concrete to be a rigid-plastic material. By extending the existing knowledge of compressive membrane action, it is possible to design slabs in building and bridge structures economically with less than normal reinforcement. Recent research on building and bridge structures reflects the importance of membrane action in design. This paper describes the finite element modelling of membrane action in reinforced concrete slabs through optimisation of a simple concrete model. Through a series of parametric studies using the simple concrete model in the finite element simulation of eight fully clamped concrete slabs with significant membrane action, a set of fixed numerical model parameter values is identified and computational conditions established, which would guarantee reliable strength prediction of arbitrary slabs. The reliability of the identified values to simulate membrane action (for prediction purposes) is further verified by the direct simulation of 42 other slabs, which gave an average value of 0.9698 for the ratio of experimental to predicted strengths and a standard deviation of 0.117. A 'deflection factor' is also established for the slabs, relating the predicted peak deflection to experimental values, which, (for the same level of fixity at the supports), can be used for accurate displacement determination. The proposed optimised concrete model and finite element procedure can be used as a tool to simulate membrane action in slabs in building and bridge structures having variable support and loading conditions including fire. Other practical applications of the developed finite element procedure and design process are also discussed.

• 한국응용과학기술학회지
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• 제32권4호
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• pp.685-693
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• 2015

본 연구에서 개발 예정인 해조류 펄프 분리 가공은 해조류자체의 배당체 및 다당류의 복합체로서 개발상 많은 어려움이 있다. 그러나 정제 공정을 개발하고 응용기술을 도입하여 아직 미개척분야인 펄프 응용기술을 확립할 수 있도록 한다. 따라서 본 제품이 개발 대량 생산되어지면 수출향상에 기여함은 물론 생분해성 기능성소재 개발의 실용화로 어민 소득증대 향상에 기여할 수 있다. 따라서 연구의 최종 목표는 1,2차년도의 기술적 데이터를 종합하여 해조류 펄프를 적용하여 생분해성이 향상되고, 고분자의 특수성질을 갖는 새로운 기능성 생분해성 플라스틱, 포장재료 등의 원재료 제품 및 시제품개발을 목표로 한다.

• 콘크리트학회지
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• 제11권1호
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• pp.267-277
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• 1999

현재 일방향 가력 해석기법은 세계적으로 기존 건물의 지진평가를 위해 구조물의 탄성 및 비탄성 거동을 예측하는데 가장 유용한 방법이다. 그러나, 이 해석기법은 특히 비내진 상세를 가진 철근콘크리트 골조에 대해 실험결과와 충분히 검토되지 않았다. 본 연구의 목적은 비내진 상세를 가진 고층 R.C. 골조에 대해 실험과 해석의 상관성을 검증하는데 있다. 본 연구의 목적은 DRAIN-2DX를 이용한 해석결과와 이미 수행된 비내진 상세를 가진 1:12축소 10층 철근콘크리트 골조의 실험결과를 서로 비교, 검토함으로써 그 응용상의 문제점과 신뢰성을 확인하는 데 있다. 본 연구는 실험과 해석의 상호 비교결과 다음과 같은 결론을 얻었다. 충전단력과 층간변위 및 소성회전각 같은 국부 변형의 전체적인 거동은 실험결과와 해석결과가 잘 일치하는 것으로 나타났다.

• Archives of Reconstructive Microsurgery
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• 제25권2호
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• pp.29-36
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• 2016

Purpose: Skin grafting is used for the transfer of cutaneous tissue from one site of the body to another. To improve graft survival, close contact between the graft and the wound bed is essential for vessels to grow across the gap. Here, we introduce an easy and efficient dressing method to improve graft survival. Materials and Methods: A retrospective chart review was performed to identify patients who underwent split thickness skin graft and negative pressure wound therapy (NPWT) or conventional treatment between January 2007 and April 2015. Overall, 25 consecutive patients were included in the NPWT group and 49 were included in the conventional dressing group to compare the outcome of the procedure. The data were obtained from medical records, including age, sex, cause of the skin defect, size of graft, time for healing, wound preparation time, and complications. Results: Of the NPWT group, the average wound size was $147.04{\pm}146.74cm^2$ (range, $9{\sim}900cm^2$). With the exception of one patient, all wounds healed without the need for further procedure. The average duration of time required for the NPWT group, which was defined as removal of stitches (or staples) and no need for additional active dressing, was $6.4{\pm}1.97days$ (range, 5~15 days). The average time for the conventional dressing group was $10.78{\pm}2.38days$ (range, 5~15 days). Conclusion: NPWT can be used to cover regions in which wound healing does not occur fully or when neither tie-over nor compressive dressings are applicable. This treatment also reduced wound healing time and allowed earlier patient mobilization and hospital discharge.