• Structural Engineering and Mechanics
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• 제27권1호
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• pp.99-115
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• 2007

In this paper, experimental investigations on the inelastic seismic behavior of tunnel form buildings (i.e., box-type or panel systems) are presented. Two four-story scaled building specimens were tested under quasi-static cyclic lateral loading in longitudinal and transverse directions. The experimental results and supplemental finite element simulations collectively indicate that lightly reinforced structural walls of tunnel form buildings may exhibit brittle flexural failure under seismic action. The global tension/compression couple triggers this failure mechanism by creating pure axial tension in outermost shear-walls. This type of failure takes place due to rupturing of longitudinal reinforcement without crushing of concrete, therefore is of particular interest in emphasizing the mode of failure that is not routinely considered during seismic design of shear-wall dominant structural systems.

• Steel and Composite Structures
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• 제42권3호
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• pp.289-298
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• 2022

In the present study, structural behavior of steel beams strengthened with CFRP strips and cables was investigated by a series of experiments. For this purpose, two groups of experimental studies were carried out: one for the beam series strengthened only with CFRP strips and the other for the steel beam series strengthened with CFRP strips and prestressed wires. From this test, it is found that the flexural stiffness and strength of the steel beams strengthened with CFRP strips and cables were significantly improved comparing to the un-strengthened one. Three failure modes such as sudden de-bonding, splitting and rupturing of CFRP strips were observed. The ultimate tensile strains of attached CFRP strips on the steel beams were noticed in the range between 8,000με and 11,000με, and this result disclose the perfect composite reaction CFRP strips and steel beams.

• 한국지반공학회지:지반
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• 제12권3호
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• pp.35-48
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• 1996

보강토구조물은 흙과 보강재 사이에 큰 변형이 발생하며 보강토구조물의 파괴양상도 보강재의 미끄러짐이나 변형에 의해 지배되며, 때때로 보강재의 재료의 파괴보다는 미끄러짐에 의해 보강토구조물이 파괴되므로 큰변형이 발생하는 흙-보강재의 모델링이 필요하다. 고형 및 액체폐기물 매립장에 쓰이는 라인너 시스템은 매립장의 경사와 쓰레기하중에 의해 큰 변형이 발생하게 된다. 이러한 큰 변형의 문제는 기존의 접촉요소로써 모델링하는데 많은 제약 이 따른다. 본 논문에서는 이러한 흙과 토목섬유보강사이의 큰 만행을 모델링할 수 있는 접촉은소를 제안하였으며, 그 이론과 그 모델의 적용성에 대하여 논하였다.

• 한국가스학회지
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• 제11권1호
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• pp.46-50
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• 2007

LPG저장설비나 용기에서 유입되는 LPG가 기화기로부터 충분한 열을 공급받지 못해 액체 상태로 기화기 출구를 통해 나가게 될 경우를 대비하여 설치한 액 유출 방지장치가 정상적으로 기화기 출구부를 차단하지 못하면 기화기 후단부에 설치한 계량기등이 LPG의 순간적인 부피팽창으로 인하여 고장나거나 파열하게 된다. 따라서 이와 같은 기화기 관련 사고를 분석하기 위하여 새롭게 개발한 투명기화통을 이용하여 기화기의 성능평가 및 액유출 방지장치를 분석하였다. 이로부터 액 유출 방지장치 플로트 밸브의 적절한 비중값과 자연대류만으로 열전달을 수행하는 LPG 기화기에 적합한 온도조절 범위를 결정하였다.

• 설비공학논문집
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• 제24권10호
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• pp.745-749
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• 2012

Heating pipes burst was occurred in the apartment complex that was applied floor radiant heating system. There were two opinions for the cause of the bursted heating pipes that was the flaw during construction and defects in the product and also there were conflicting among them. Officials analyzed it in order to investigate the cause of the rupture. Tensile test results showed different tensile strength between the lower part of heating pipe and the upper part of heating pipes. The lower tensile strength is maintained while the top was not secured. The reason why rupture heating pipes is that flow velocity isn't secured and then the air get stagnant. Stagnant air makes hardening. It is caused rupturing. The proper flow rate was confirmed 0.166 m/sec after experiment. It isn't make stagnant air inside heating pipes.

• Journal of Korean Neurosurgical Society
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• 제53권5호
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• pp.300-302
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• 2013

Reports of traumatic leptomeningeal cysts (TLMC) are rare in adults. The standard treatment approach is craniectomy with careful exposure of the intact dural edges, followed by duroplasty. However, occasionally, the location of the TLMC makes achieving watertight duroplasty impossible. Herein, we report the case of a 28-year-old male who presented with a soft growing mass on the vertex of his head 16 months after the head trauma. Upon enhanced CT examination, a bony defect involving both the inner and outer table of the cranium was observed close to the sagittal sinus, and a well-defined cystic mass, 5 cm in diameter, was nested within the defect. The risks associated with extension craniotomy were high because the lesion was located superficial to the sagittal sinus, we opted to use fibrinogen-based collagen fleece (TachoCombR$^{(R)}$) to repair the dural defect. Two months after surgery, the patient remained asymptomatic with a good cosmetic result. In cases like ours, when the defect is near the major sinuses and the risk of rupturing the sinus during watertight dural closure is high, fibrinogen-based collagen fleece (TachoCombR$^{(R)}$) is an effective alternative approach to standard dural suture techniques.

• 대한족부족관절학회지
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• 제10권2호
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• pp.259-263
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• 2006

The acute Achilles tendon rupture usually occurs to the people who participate in sports-related activities between 30 and 40 years of age. Recently surgical repair is the standard treatment in acute Achilles tendon rupture. After the Achilles tendon rupture in the left ankle, a 30-years old young man had been suffered from re-rupturing within three months after the primary repair. 2 years later, right-side Achilles tendon was reruptured after primary repair consequently. In the revision surgery, we performed V-Y advancement of the gastrocnemius-soleus fascia and reinforcement of the semitendinosus tendon. None of the English-literature was reported about using the semitendinosus tendon in revision surgery of the Achilles tendon retear previously. Therefore, we report this case and surgical technique because of the simple technique and the excellent results.

• Corrosion Science and Technology
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• 제11권3호
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• pp.89-95
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• 2012

U.S. Electric Power Research Institute (EPRI) has developed CHECWORKS program and applied it to power plant piping lines since some lines were ruptured by flow-accelerated corrosion (FAC) in 1978. Nowadays the CHECWORKS program has been used to manage pipe wall thinning phenomena caused by FAC. However, various erosion mechanisms can occur in carbon-steel piping. Most common forms of erosion are cavitation, flashing, liquid droplet impingement erosion (LDIE), and Solid Particle Erosion (SPE). Those erosion mechanisms cause pipe wall thinning, leaking, rupturing, and even result in unplanned shutdowns of utilities. Especially, in two phase condition, LDIE damages a wide scope of plant pipelines. Furthermore, LDIE is the major culprit to cause such as power runback by pipe leaking. This paper describes the methodologies that manage wall thinning and also predict LDIE wall thinning area. For this study, current properties of two-phase condition are investigated and LDIE areas are selected. The areas are checked by B-Scan method to detect the effect of wall thinning phenomena.

• 미생물학회지
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• 제38권2호
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• pp.103-106
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• 2002

사상균류의 세포자체로부터 직접 PCR을 하는 방법은 세포벽 파괴의 어려움 때문에 모든 곰팡이에 적용될 수 없다. 극초단파 조사는 사상균류의 DNA를 추출함에 있어서 그 유용함이 이미 검중된 바 있는데, 본 논문에서는 극초단파 조사를 이용하여 Aspergillus nidulans의 포자로부터 손쉽게 주형 DNA를 얻어 PCR증폭하는 방법을 소개하고자 한다. 본 실험에서는 극초단파 조사시간과 PCR에 필요한 주형 DNA의 양 등을 최적화하였으며, 이렇게 수행된 PCR결과는 single copy유전자를 대상으로도 약 3 kb크기의 산물가지 증폭 가능하여, 형질전환체를 선별하기에 충분한 크기의 산물들도 효과적으로 얻어짐을 보여주었다. 따라서 이 방법은A. nidulans의 형질전환체를 보다 손쉽게, 시간을 절약하여 선별할 수 있는 효과적인 방법이라 생각된다.

• Food Science and Biotechnology
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• 제15권4호
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• pp.506-510
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• 2006

To be used as a source of astaxanthin by animals, the red yeast Xanthophyllomyces dendrorhous needs to be dried and the cell wall ruptured. Spray-drying and flat-roller milling successfully prepared the yeast as a feed additive with little loss of astaxanthin. Spray-drying successfully dried the yeast with negligible decomposition of astaxanthin compared to drum-drying. By repeated milling with a flat-roller mill, astaxanthin extracted with ethanol increased from 0.01 to 1.31 mg astaxanthin/g yeast. This method did not decompose astaxanthin in contrast to chemical digestion of the cell wall. Flat-roller milling effectively flattened and cracked the dried cells. Astaxanthin in yeast prepared by spray-drying and flat-roller milling was well absorbed by animals. Specifically, when spray-dried and milled yeast was supplied in the feed (40 mg astaxanthin/kg feed), astaxanthin was successfully absorbed (1,500 ng/mL blood and 1,100 ng/g skin) by laying hens.