• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 추계 학술발표회 제17권2호
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• pp.363-366
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• 2005

When widening or repairing concrete deck slab, there is a joint inevitably. However, joining-construction method have following problem, that is the additional stress in existing part of bridge resulting from the specific process of joining-construction and the difference of amount of shrinkage between new and existing bridge. On this study, compared shrinkage stress of the direct joining construction method with the indirect joining construction method, and concluded the proper substitution rate of expansion cement. The rate of replacement was proper at $10\%$. but more than $15\%$, concrete had excessive expansion and weeker compressive strength. The time of placing closure concrete, considering the shinkage stresses and creep, was suitable in $45\~60$ days after placing the new concrete deck slab.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2001년도 봄 학술발표회 논문집
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• pp.335-342
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• 2001

In this paper, an improved Element-Free Galerkin (EFG) method is proposed by adding enrichment function to the standard EFG approximation and a discontinuity function is implemented in constructing the shape function across the crack surface. In this method, the singularity and the discontinuity of the crack are efficiently modeled by using initial node distribution to evaluate reliable stress intensity factor, though the standard EFG method requires placing additional nodes near the crack tip. The proposed method enables the initial node distribution to be kept without any additional nodal d.o.f. and expresses the asymptotic stress field near the crack tip successfully. Numerical example verifies the improvement and the effectiveness of the method.

• 한국해안·해양공학회논문집
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• 제32권6호
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• pp.516-523
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• 2020

항만구조물의 노후화가 가속화되면서 상향된 설계파 조건에 대응하기 위한 연구가 필요한 상황이다. 특히 피복재가 거치되는 경사식구조물의 경우, 상향된 설계파고에 안정중량을 확보하기 위해서는 피복재의 중량 증가가 필요하다. 그렇지만 그와 관련된 연구는 진행된 사례가 없다. 본 연구에서는 기존 피복재가 거치된 경사식구조물에 추가 피복재를 거치하는 경우, 추가 피복재의 안정중량 산정을 위한 수리모형실험을 수행하였다. 피복재로는 콘크리트 이형블록인 테트라포드를 적용하였다. 실험결과에 의하면 비월파 조건에서 기존 피복재(테트라포드)가 정적 거치이고 사면경사의 변화가 거의 없는 경우 실험조건 내에서 추가피복재(테트라포드)의 안정계수(Kd)는 일반적인 테트라포드 안정계수(Kd = 8)에 비하여 주기별로 차이가 있으나 최대 10% 증가하는 것으로 나타났다.

• 설비공학논문집
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• 제2권4호
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• pp.295-302
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• 1990

The purpose of this study is augmentation of heat transfer without additional power in two-dimensional impinging air jet. The technique of heat transfer augmentation used in this experiment is to place rod bundles in front of the flat heated surface. The effects of rod diameter, nozzle-to-target plate distance and the nozzle exit velocity on heat transfer have been investigated. The main conclusions obtained from this experiment are as follows. High heat transfer augmentation is achieved by means of flow acceleration and thinning of boundary layer by placing rod bundles in front of the flat plate. Average heat transfer coefficient becomes maximum in the case of H/B=10,D=4mm. For H/B=2,D=4mm, maximum heat transfer augmentation has been determined to be about 1.5 times larger than that of the flat plate. Heat transfer augmentation by placing the rod bundles at 12m/s is to be about 2 times more than increasing nozzle exit velocity from 12m/s to 18m/s.

• 동의생리병리학회지
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• 제29권3호
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• pp.240-245
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• 2015

Pulse diagnosis, the most popular diagnostic tool in traditional Korean medicine, had had many forms but had been fixed on using wrist pulse and placing internal organs on Cun, Guan and Chi(寸 關 尺). Wang Shuhe(王叔和) suggested placing six viscera(六腑) on Cun, Guan and Chi based on relationship between external and internal meridian vessel, and Zhang Jiebin(張介賓) criticized his suggestion and insisted that pulse diagnosis should be based on the organ system. But the origin of pulse diagnosis which can be found in "(Huangdi's) Internal Classic(黃帝內經)" is a tool mainly for diagnosis of not internal organ system but meridian system. Most of material about pulse diagnosis after Ming dynasty(明代) reinterpreted pulse diagnosis in the aspect of organ system, So there has to be additional discussion about it.

• 대한방사선기술학회지:방사선기술과학
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• 제44권6호
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• pp.629-633
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• 2021

This article is designed to look into the radiation exposure dose to each body part and the shielding effect for workers using an additional shielding to reduce their radiation exposured by scattering radiation which is generated in a space between the operating table and lead curtain during interventional radiology(IR) procedures. After placing a human phantom on the table of SIEMENS' angiography machine, the following measurements were taken, depending on the presence of an additional shield of lead equivalent of 0.25 mmPb, manufactured for this purpose: dose to gonad, dose to an area where the personal dosimeter is placed, and dose to an area of eye lens is located. An ion chamber(chamber volume 1,800 cc) was utilized to measure scattering radiation. The two imaging tests were carried out as follows: fluoroscopy of the abdomen (66 kV, 100 mA, 60 seconds) and of the head (70 kV, 65 mA, 60 seconds); and digital subtraction angiography(DSA) of the abdomen (67 kV, 264 mA, 20 seconds) and of the head (79 kV, 300 mA, 20 seconds). In all the experiments, the shielding efficiency of the gonad position was the largest at 59.8%. In case an additional shielding was used as protection against scattering radiation that came through the operating table and the lead curtain during an IR, the radiation shielding efficiency was estimated to be up to 59.8%, leading to a conclusion that its presence may effectively reduce the radiation exposure dose of medical staffs.

• Computers and Concrete
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• 제7권6호
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• pp.523-532
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• 2010

If an infill wall in a reinforced concrete frame is shorter than the column height and there is no initial gap between the column and the infill wall, the short column effect can occur during an earthquake shaking. This form of damage is frequently observed in many earthquake-damaged buildings all around the world and especially in Turkey. In this study, an effective method, which consists of placing additional infill wall segments surrounding the short column, to prevent this type of failure is examined. The influence of adding infill wall in the reduction of the shear force in the short column is also investigated. A parametric study is carried out for one-storey infilled frames with one to five bays using the percentage of the additional infill wall surrounding the short column and the number of spans as the parameters. Then the investigation is extended to a case of a multistorey building damaged due to short column effect during the 1998 Adana-Ceyhan earthquake in Turkey. The results show that the addition of the infill walls around the potential short columns is an effective way to significantly reduce the shear force.

• Plant Resources
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• 제1권2호
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• pp.98-104
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• 1998

The effects of basal media, sucrose and phytohormone concentrations, and gelling agent combinations on in vitro frond proliferation of Lemna gibba G3 and 24 additional Lemna gibba strains were examined. Frond proliferation was equivalent on Schenk and Hidebrand. Murashige and Skoog. Nitsch and Nitsch, and Gamborg's B5 media and poor on murashige and Skoog medium in the absence of benzyladenine. With the addition of benzyladenine, Schenk and Hildebrand and Gamborg's B5 Were superior and equivalent. The addition of benzuyladenine increased equally frond proliferation at either 1 or $10{\mu}M$, however at $10{\mu}M$ fronds were severely curled or fused. Benzyladenine and thidiazuron suppressed root growth but kinetin was found to greatly enhance root growth. Gibberellic acid inhibited frond proliferation. Frond proliferation was significantly different on the four sucrose concentrations of 0, 1, 3, and 5% Among them, 3% sucrose was found to be superior. The reduced frond size observed in cultures grown on 8% sucrose could be explained by showing medium osmotic potential in excess of frond water potential. Gell agents also varied significantly in their ability to promote frond proliferation with 0.25% Gelrite or a mixture of 0.15% Gelrite and 0.4% agar. Proliferation of 25 Lemna gibba strains on medium neat optimal for Lemna gibba G3 showed a six-fold variation across strains with Lemna gobba G3 placing in the top 5 fastest proliferating strains.

• Journal of Chest Surgery
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• 제30권4호
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• pp.428-431
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• 1997

승모판파 재치환술후 발생하는 판막주위 누출은 판륜 주위에 잔촌하는석회화나 약한 판륜조직에 의해서 발생한다. 이는 임상적으로 혈관내 용혈성 빈혈이나 혈역학적 인 변화를 야기하는데 서서히 나타나기 때문에 외래에서의 추적 관찰이 중요하다. 재치환한 판막의 구조적인 변화가 없고 비교적 적은 부위의 판막주위 누출이고 기존의 판륜이 약해져 있는 경우에는 새로이 판막을 치환하는 것보다 단순히 패취로 복구시 킬 수 있다.

• ETRI Journal
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• 제31권6호
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• pp.778-783
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• 2009

To fabricate uniform and reliable thin gold stripes that provide low-loss optical waveguides, we developed a novel liftoff process placing an additional $SiN_x$ layer under conventional photoresists. By patterning a photoresist and over-etching the $SiN_x$, the photoresist patterns become free-standing structures on a lower-cladding. This leads to uniform metal stripes with good reproducibility and effectively removes parasitic structures on the edge of the metal stripe in the image reversal photolithography process. By applying the newly developed process to polymer-based gold stripe waveguide fabrication, we improved the propagation losses about two times compared with that incurred by the conventional image-reversal process.