• Structural Engineering and Mechanics
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• 제84권1호
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• pp.129-141
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• 2022

It has previously been proposed that the yield-line method of analysis for reinforced concrete slabs could be automated via the use of rigid finite elements, assuming all deformations occur along element edges. However, the solutions obtained using this approach can be observed to be highly sensitive to mesh topology. To address this, a revised formulation that incorporates modified yield criteria to account for the presence of non-zero shear forces at interfaces between elements is proposed. The resulting formulation remains simple, with linear programming (LP) still used to obtain solutions for problems involving Johansen's square yield criteria. The results obtained are shown to agree well with literature solutions for various slab problems involving uniform loading and a range of geometries and boundary conditions.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1998년도 가을 학술발표대회 논문집(III)
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• pp.809-814
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• 1998

Recently many cases that using strengthening method with a steel plate or carbon-fiber sheet in a construction field are increasing. In this reason, it is demanded that developing a plan of preventing delamination of strengthening material. So in this research, for the case of strengthening method of steel plate, it is made use of notch and anchor bolt and for the case of carbon fiber sheet, it is made use of notch, anchor bolt, line anchor and shear strengthening. After all the cases were applied, we made 15 specimen beams. The beams was measured and analyzed about the behavior property of strengthened beams, the ability strengthening method, the relation between load and the shape of failure, the crack load, the yield load, the shape of crack pattern, the increasing rate from yield load and maximum load and the strain of rebar. All the strengthening methods results in almost same value until the yield load, and it wasn't quite different from the theoretical value. But for the case of increasing rate from the yield load and maximum load, comparing with the existing method, the new strengthening methods are proved to be profitable about the safety.

• 대한토목학회논문집
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• 제8권2호
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• pp.51-58
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• 1988

철근(鐵筋)콘크리트 설계(設計)를 위하여 강복선이론(降伏線理論)을 이용하는 경우에는 강복선(降伏線)을 따라서 발생(發生)하는 과도(過度)한 모멘트분배(分配)로 인하여 국부적(局部的)인 파괴(破壞)가 일어날 수 있다. 주열대(柱列帶)의 중간대(中間帶)의 소성저항(塑性抵抗)모멘트를 하나의 매개변수(媒介變數)를 이용하여 다르게 취하므로써 이러한 국부적(局部的) 파괴(破壞)를 줄일 수 있는 강복선이론(降伏線理論)에 의한 해석공식(解析公式)이 제안(提案)되었다. 또한 강복선이론(降伏線理論)에 의한 해석공식(解析公式)에 포함되어 있는 여러 가지 매개변수(媒介變數)들의 이상적(理想的)인 값을 제안(提案)하므로써 강복선법(降伏線法)에 의한 철근(鐵筋)콘크리트 슬래브의 설계(設計)를 보다 용이하고 합리적(合理的)으로 실시할 수 있게 하였다.

• 한국식품영양학회지
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• 제1권2호
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• pp.31-36
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• 1988

An adaptive on-line optimization method has been applied to test the ability to maximize the cellular productivity of a continuous methylotroph culture system which was simulated by a variable yield Monod-type model. Optimum dilution rate and productivity were successively obtained and maintained at all times by the algorithm that utilizes steepest descent technique as optimization method and recursive least-square method with forgetting factor as dynamic model identification.

• Computers and Concrete
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• 제3권6호
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• pp.439-454
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• 2006

This paper develops an artificial neural network (ANN) model for uniformly loaded restrained reinforced concrete (RC) slabs incorporating membrane action. The development of membrane action in RC slabs restrained against lateral displacements at the edges in buildings and bridge structures significantly increases their load carrying capacity. The benefits of compressive membrane action are usually not taken into account in currently available design methods based on yield-line theory. By extending the existing knowledge of compressive membrane action, it is possible to design slabs in building and bridge decks economically with less than normal reinforcement. The processes involved in the development of ANN model such as the creation of a database of test results from previous research studies, the selection of architecture of the network from extensive trial and error procedure, and the training and performance validation of the model are presented. The ANN model was found to predict accurately the ultimate strength of fully restrained RC slabs. The model also was able to incorporate strength enhancement of RC slabs due to membrane action as confirmed from a comparative study of experimental and yield line-based predictions. Practical applications of the developed ANN model in the design process of RC slabs are also highlighted.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.251.1-251.1
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• 2013

Combination of oxidative vacuum annealing and oxygen plasma treatment can serve as a simple and efficient method of line-width modification of imprinted nanopatterns. Since the vacuum annealing and oxygen plasma could lead mass loss of polymeric materials, either one of the process can yield a narrowed patterns. However, the vacuum annealing process usually demands quite high temperatures (${\geq}300^{\circ}C$) and extended annealing time to get appreciable line-width reduction. Although the plasma treatment may be considered as an effective low temperature rapid process for the line-width reduction, it is also suffering for the lowered controllability on application to very fine patterns. We have found that the vacuum annealing temperature can be lowered by introducing the oxygen in the vacuum process and that the combination of oxygen plasma treatment with the vacuum annealing could yield the best result in the line-with reduction of the imprinted polymeric nanopatterns. Well-defined line width reduction by more than 50% was successfully demonstrated at relatively low temperatures. Furthermore, it was verified that this process was applicable to the nanopatterns of different shapes and materials.

• Journal of Applied Biological Chemistry
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• 제57권4호
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• pp.301-305
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• 2014

On-line screening high performance liquid chromatography (HPLC)-$ABTS^+$ assay를 이용한 청호로부터 chlorogenic acid, caffeic acid, vitexin, queretin, aremisinin의 항산화 활성을 온라인스크리닝 하였다. 이때 침적방법을 적용한 추출시간과 추출용매 조성으로부터 추출효율을 확인하였다. 이 결과 100% 물 추출물에서 수율이 가장 좋왔고 chloroenic acid의 항산화 활성이 가장 높았다. 또한 on-line screening HPLC-$ABTS^+$ assay 분석은 천연물에서 항산화 활성을 신속하게 탐색하는데 효율적이다.

• 한국작물학회지
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• 제53권4호
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• pp.388-393
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• 2008

광범위한 지역의 재배면적과 생산량을 신속하고 경제적으로 모니터링 할 수 있는 광학(LANDSAT) 중해상도 위성 영상을 활용하여 벼 재배면적, 생육 및 수량을 모니터링 할 수 있는지를 검토하였다. 1. 식생지수와 수량과의 관계를 살펴보면, EVI를 제외한 모든 식생지수와 수량간에는 정의 상관관계를 보였으며, NDVI_SWIR이나 EVI_SWIR과는 유의성이 없었다. NDVI가 RVI보다 수량과의 상관도가 다소 높았으며, 수량과 가장 밀접한 식생지수는 $NDVI_R$(r = 0.68)이었다 2. LANDSAT 단일시기 영상(2004년 7월 29일)을 활용하여 서산간척지 지역내 벼 수량을 모니터링한 결과 $NDVI_R$와 백미수량간에는 1차 직선관계($R^2$ = 0.46)가 성립하였으며, 필 지중에서 면적이 다소 적거나 주변에 반사특성에 영향하는 요인이 있는 지역을 제외하여 살펴본 결과 추정도가 다소 높아졌다($R^2$ = 0.66). 3. 논구역 벡터를 사용하여 논구역 정보를 추출하는 기존의 방법 대신 raster 기반의 논구역 masking을 제작하여 논 구역 정보를 추출하였는데 이 방법을 통해 쉽고 빠르게 논구역 정보를 추출할 수 있었다. 4. 연차별 지역적용가능성을 검토하기 위해 1994년 7월 26일 경기도내 7개 시군의 논구역 masking을 제작하여 NDVIred를 추출하고 $NDVI_R$-수량관계식을 이용하여 수량을 추정한 결과 1:1 line에 근접하여 비교적 잘 일치되었다.

• 대한전자공학회논문지SD
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• 제46권9호
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• pp.14-24
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• 2009

System on panel 프레임 버퍼를 위한 메모리 셀 어레이와 주변회로가 설계되었다. 또한, system on panel 공정의 낮은 yield를 극복하기 위해, 블럭 단위의 parallel test 방안이 제안되었다. 기존의 메모리 테스트 보다 빠르게 fault detection이 가능하며, 다양한 embedded memory나 일반 SRAM 테스트 분야에도 적용 가능하다. 또한 기존의 다양한 test vector pattern이 그대로 적용될 수 있어 fault coverage가 높고, 최근의 추세인 hierarchical bit line과 divided word line 구조에도 적용될 수 있다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 봄 학술발표회 논문집(I)
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• pp.727-732
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• 1999

In this research, we made an experiment on the 10 specimen beams that we made. The specimen beams consist of 4 steel plate strengthening beams and 5 carbon fiber sheet strengthening beams. We applied the methods of notch, rounding off a edge, anchor bolt and side shear strengening to the steel plate and for the case of carbon fiber sheet, we applied the methods of anchor bolt, line anchor and shear strengthening. After all the cases were applied, the beams was measured and analyzed about the behavior property of strengthened beams, th ability of strengthening method, the relation between load and the shape of failure, the crack load, the yield load, the shape of crack pattern, the increasing rate from yield load and maximum load and the strain of rebar. All the strengthening methods resulted in almost same value until the yield load, and it wasn't quite different from the theoretical value. In comparison with existing method, the SER, SEAS for the steel plate and the CEA, CESS, CCESS for carbon fiber sheet showed the increasement of ductility with big displacement.