• Proceedings of the Korea Concrete Institute Conference
• /
• 2005.05a
• /
• pp.143-146
• /
• 2005

최근 들어 90도 표준갈고리의 대안으로 정착판을 지니는 헤드 철근(headed bar)에 대한 관심이 높아지고 있다. 헤드 철근의 정착내력은, 정착판의 지압력과 위험단면에서 헤드까지 정착길이의 부착력으로 발현된다. 실제 구조물에서는 정착되는 부재의 재료 및 기하학적 물성에 의해 다양한 파괴가 발생된다. 따라서 헤드 철근의 정착내력은 단순히 지압력과 부착력의 합으로 산정될 수 없으며, 발생 가능한 모든 파괴양상을 고려한 최소 내력으로 결정되어야 한다. 헤드 철근의 정착내력을 산정하기 위한 기본적인 해석모델로, CCT 절점에 정착된 헤드 철근의 트러스 모델을 제안하였다. 제안된 트러스 모델의 파괴는 부착파괴와 콘크리트의 압축파괴로 구분되며, 재료 및 기하학적 물성에 의해 파괴 양상이 결정된다. 이러한 트러스 모델은 외부 보-기둥 접합부와 같이 보다 복잡한 부위에 정착된 헤드철근의 정착 기구를 설명하는데 활용될 수 있다.

• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2020.07a
• /
• pp.675-679
• /
• 2020

최근 이미지 분류의 성능 향상을 위해 깊은 레이어와 넓은 채널을 가지는 모델들이 제안되어져 왔다. 높은 분류 정확도를 보이는 모델을 제안하는 것은 과한 컴퓨팅 파워와 계산시간을 요구한다. 본 논문에서는 이미지 분류 기법에서 사용되는 딥 뉴럴 네트워크 모델에 있어, 프루닝 방법을 통해 상대적으로 불필요한 가중치를 제거함과 동시에 분류 정확도 하락을 최소로 하는 동적 필터 프루닝 방법을 제시한다. 원샷 프루닝 기법, 정적 필터 프루닝 기법과 다르게 제거된 가중치에 대해서 소생 기회를 제공함으로써 더 좋은 성능을 보인다. 또한, 재학습이 필요하지 않기 때문에 빠른 계산 속도와 적은 컴퓨팅 파워를 보장한다. ResNet20 에서 CIFAR10 데이터셋에 대하여 실험한 결과 약 50%의 압축률에도 88.74%의 분류 정확도를 보였다.

• Prospectives of Industrial Chemistry
• /
• v.22 no.6
• /
• pp.2-12
• /
• 2019

최근 암 면역치료는 임상연구에서 긍정적인 결과를 보이고 있으며 암 질환의 표준치료법으로 자리 잡아가고 있다. 암 면역치료는 암의 재발과 전이를 획기적으로 개선시킬 수 있다는 이점이 있다. 하지만 전체 암 환자의 15~20%에서만 치료 효과를 보이고 심각한 부작용을 유발할 수 있다는 임상적 한계가 있다. 이러한 문제점들을 개선하기 위해서 기존에 약물전달 또는 조직공학 분야에서 활용되었던 생체재료를 도입하여 면역치료의 효과를 개선하고 부작용은 줄이려는 시도가 활발하다. 본 기고문에서는 효율적인 암 면역치료를 위한 생체재료(나노입자, 리포좀, 미립구, 및 하이드로젤)에 관한 최신 연구동향을 다루고자 한다. 고기능성 생체재료 개발과 종양 면역학 분야의 깊은 이해는 효과적인 암 면역치료제를 개발하는데 있어서 매우 중요하다.

• Journal of the Korean Geosynthetics Society
• /
• v.20 no.2
• /
• pp.45-56
• /
• 2021

As the utilization of the underground space is activated, deep excavation of ground has been conducted for the installation of underground structures, the earth retaining wall has widely used to minimize deformation of the excavated ground. In particular, as deep excavation is actively progressing in an urban area where structures are concentrated, methods to minimize the deformation of wall have been devised to prevent damage to the structure adjacent to the wall, and one of these methods is the pre-loading method. This method is a method of suppressing the deformation of wall by actively applying a load on the strut to be installed in wall, and research on this method has been conducted recently. However, although related studies have been actively conducted, the management standard for the pre-loading of bracing has not been clearly presented until now. In addition, since the working force in the strut may increase depending on the depth of excavation or the soil condition of the backfill, the magnitude of the pre-loading that can be applied to the brace may decrease. Nevertheless, the magnitude of the pre-loading (more than 50% of the working load) proposed by the previous research results has been uniformly applied to the strut. In this study, 3D finite element analysis was performed to evaluate the application range of the pre-loading of H-beam strut according to the soil conditions of backfill. As a result of the analysis, it was found that there is a very high possibility that a problem may occur in the stability of the structure of strut due to the earth pressure and the pre-loading when the soil condition is weak and deep excavation proceeds. And it was found that the application range of the pre-loading was 5%~70% of the working load in strut.

• Korean Journal of Ichthyology
• /
• v.2 no.2
• /
• pp.182-202
• /
• 1990

Gobiid fish were collected monthly in Cheonsu Bay by a beach seine from the shallow water and by an otter trawl from the deep water from September, 1984 to August, 1986. Seasonal variation in species composition and biology of the major species were examined with the data of length and age composition. Fourteen speices of gobies were identified. Gobiid fish were more abundant in the shallow water than in the deep water. In the shallow water, they constituted 66% and 39% of the fish collected in the mud flat and the sand beach, respectively. The suction discs of the gobies explains that they inhabit successfully in the surf zone where the wave action is strong. Of the major species, Chaenogobius mororanus predominated in the shallow mud flat. A large number of adults of this species were obtained in Spring and their juveniles were collected from Summer through Autumn. Favonigobius gymnauchen was abundant in the shallow water, especially in the sand beach. This fish seemed to spawn from May through June, about two months later than Chaenogobius mororanus. Acanthogobius hasta juveniles lived in the shallow water and moved into the deep water as the fish grew. Chaturichthys stigmatias was collected mainly in the deep zone.

• Journal of the Korea Concrete Institute
• /
• v.23 no.3
• /
• pp.273-280
• /
• 2011

Ten high-strength concrete beam specimens, which have various combinations of different types of flexural reinforcement and short fibers were constructed and tested. Six beams were reinforced with two layers of steel, CFRP, and GFRP bar combinations. The other four beams were reinforced with two layers of single type CFRP and GFRP bars, with steel and synthetic short fibers. An investigation was performed on the influence of the parameters on the load-carrying capacity, post cracking stiffness, cracking pattern, deflection behavior, and ductility. The low post cracking stiffness, large deflection, deep crack propagation, large crack width, and low ductility of FRP bar-reinforced beams were controlled and improved by positioning steel bars in the inner layer of the FRP bar layer. In addition, the addition of fibers increased the first-cracking load, ultimate flexural strength, and ductility as well as the deep propagating cracks were controlled in the FRP bar-reinforced concrete beams. The increased ultimate concrete strain of fiber-reinforced concrete should be determined and considered when FRP bar-reinforced concrete members with fibers are designed.

• Journal of Korean Society of Steel Construction
• /
• v.16 no.6 s.73
• /
• pp.747-757
• /
• 2004

With steel and concrete composite beams, the incomplete interaction between the steel and the concrete slab leads to an appreciable increase in beam deflections. Moreover, encased composite beams using a deep deck plate or hollow-core PC slabs are critical to deflection due to their inherent geometry. In this paper, by using the calculation tools that were developed for a previous study on the deflection of encased composite beams considering the slip effects and load-slip curve, the shear bond stress and additional deflection induced due to interface slip of the encased composite beam are presented. It was found that the slip effects significantly contribute to the encased composite beam deflections and result in stiffness reduction of up to 30% compared to that of full shear interaction beams. The predicted results were compared with the measurement of 18 specimens tested in this study, and comparisons show a high degree of accuracy, within 6%.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.48 no.1
• /
• pp.1-6
• /
• 2011

We have developed the process of forming one body S-type cantilever probe in the recessed trench for fine-pitched MEMS probe card. The probe (cantilever beam and pyramid tip) was formed using Deep RIE etching and wet etching. The pyramid tip was formed by the wet etching using KOH and TMAH. The process of forming the curved probe was also developed by the wet etching. Therefore, the fabricated probe is applicable for the probe card for DRAM, Flash memory and RF devices tests and probe tip for IC test socket.

• Resources Recycling
• /
• v.10 no.1
• /
• pp.7-15
• /
• 2001

We can reuse the portion of simple reclamation and the construction by-products. Until now, we have discarded concrete by simply throwing away or dumping in underground. Therefore, we attempted to propose the technical directions for the reuse of waste concrete as the recycled concrete aggregates and concrete structural materials. As a testing result, It is reasonable that standards are substitution of recycled aggregates under 30%, maximum steel ratio, under 70% of balanced steel ratio, under shear span ratio 0.2 for deep beam criteria for safety and Zsutty's equation is reasonable for estimation of factored shear strength

• Ocean and Polar Research
• /
• v.36 no.2
• /
• pp.111-119
• /
• 2014

This study examined the spatial and temporal variation of dissolved inorganic radiocarbon in the East Sea. Five vertical profiles of radiocarbon values were obtained from samples collected in 1999 in three basins (Japan Basin, Ulleung Basin, Yamato Basin) of the East Sea. Radiocarbon values decreased from 63- 85‰ at the surface to about -50‰ with increasing depth (up to 2,000 m) and were nearly constant in the layer deeper than 2,000 m in all basins. Radiocarbon values did not show significant basin-to-basin differences in the surface and the bottom layers. In the intermediate layer (200-2,000 m), however, they decreased in the order of Japan Basin > Ulleung Basin > Yamato Basin, which is consistent with the suggested circulation pattern in the intermediate layer of the East Sea. Radiocarbon was found to have decreased at ~2%/year in the surface water of the East Sea. In contrast, in the interior of the East Sea, radiocarbon values have increased with time in all three basins. In the Central Water, the annual increase rate was about 3.3‰, which is faster than the rates in the Deep and Bottom Waters. The radiocarbon in the Deep and Bottom Waters had increased until mid-1990s, after which time it has been almost constant.