• Industrial Engineering and Management Systems
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• 제12권2호
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• pp.85-94
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• 2013

This research investigates the supply chain contract between a distributor and a supplier in which the selling period is relatively short in comparison with long production lead time. At the first stage, supplier who is a Stackelberg leader offers the distributor a contract with a set of parameters, and subjected to those parameters, the distributor places the number of initial orders as well as options. In order to purchase the option, the distributor pays non-linear option premium price with respect to the number of purchased options. At the second stage, based on realized demand, the distributor has the right to exercise option as either put or call which is limited up to the number of purchased options. The wholesale price contract is used as a benchmarking contract. This research has confirmed that the supply chain contract with a non-linear option premium price can help to coordinate the supply chain.

• Fisheries and Aquatic Sciences
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• 제18권3호
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• pp.287-296
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• 2015

Although rotifers have been considered the best feeding option for several species of fishes in aquaculture, they are sometimes larger than appropriate for the early larval stage of some marine fishes. Thus, we aimed to determine whether size-based selection of the parents could affect the average body size of their progeny in two clonal populations of the rotifer Brachionus rotundiformis. From each of the clones, 20 individuals were bi-directionally selected toward both smaller and larger sizes and each individual-based selection was conducted for 10 consecutive generations. The results showed that although there were sometimes differences in mean body size between parents and their progeny, no directional trend was observed in all selected lines of both clones. We demonstrated that artificial selection in a rotifer stock cannot lead to an expected size range although they appear to exhibit a large degree of body size polymorphism.

• 한국유체기계학회 논문집
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• 제16권4호
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• pp.35-43
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• 2013

Most of the nuclear power plants(NPPs) adopts pressure difference type flow meters such as venturi and orifice meters for the measurement of feedwater flow rates to calculate reactor thermal power. However, corrosion products in the feedwater deposits on the flow meter by fouling as operating time goes. These effects lead to severe errors in the flow indication and then determination of reactor thermal power. The averaging BDFT, which has developed by Yun et al., has a potentiality to minimize this problem thanks to its inherent measurement principle. Therefore, it is expected that the averaging BDFT can replace the venturi meter for the feedwater pipe of steam generator of NPPs. The present work compares the amplification factor, K, based on CFD calculation against the K obtained from experiments in order to confirm whether a commercial CFD code can be applicable to the evaluation of characteristic for the averaging BDFT. In addition to this, the simulations to take into account of fouling effect are also carried out by rough wall option. The results show that the averaging BDFT is a promising flow meter for the accurate measurement of flow rates in the fouling condition of the NPPs.

• Archives of Plastic Surgery
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• 제48권1호
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• pp.69-74
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• 2021

Background In inferomedially rotated zygomatic fractures sticking in the maxillary sinus, it is often difficult to achieve complete reduction only by conventional intraoral reduction. We present a new intraoral reduction technique using a Kirschner wire and its clinical outcome. Methods Among 39 inferomedially impacted zygomatic fractures incompletely reduced by a simple intraoral reduction trial with a bone elevator, a Kirschner wire (1.5 mm) was vertically inserted from the zygomatic body to the lateral orbital rim in 17 inferior-dominant rotation fractures and horizontally inserted to the zygomatic arch in nine medial-dominant and 13 bidirectional rotation fractures. A Kirschner wire was held with a wire holder and lifted in the superolateral or anterolateral direction for reduction. Following reduction of the zygomaticomaxillary fracture, internal fixation was performed. Results Fractures were completely reduced using only an intraoral approach with Kirschner wire reduction in 33 cases and through an additional lower lid or transconjunctival incision in six cases. There were no surgical complications except in one patient with undercorrection. Postoperative 6-month computed tomography scans showed complete bone union and excellent bone alignment. Four patients experienced difficulty with upper lip elevation; however, these problems spontaneously resolved after manual tissue lump massage and intralesional steroid (Triamcinolone) injection. Conclusions We completely reduced infraorbital rim fractures, zygomaticomaxillary buttresses, and zygomaticofrontal suture fractures in 84% of patients through an intraoral approach alone. Intraoral Kirschner wire reduction may be a useful option by which to obtain effective and powerful reduction motion of an inferomedially rotated zygomatic body.

• Journal of Chest Surgery
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• 제39권3호
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• pp.177-183
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• 2006

배경: 양방향성 상대정맥-폐동맥 단락술은 복잡심기형의 일차적 고식수술 중 하나로, 여러가지 장점이 있으나 유아 환아들에서는 수술 후 위험성이 높은 것으로 알려져 있다. 대상 및 방법: 1995년부터 2003년까지 48명의 1세 이하 환아들이 연세대학교 심장혈관병원에서 양방향성 상대정맥-폐동맥 단락술을 시행 받았다. 모든 환아들은 단심실로 인한 폰탄수술의 대상자였다. 환아들은 수술당시의 나이에 따라 두 군으로 분류되었다 A군(<3개월, 12명)과 B군(3${\~}$12개월, 36명) 간에 평균 나이(67.58$\pm$3.78 vs. 212.91 $\pm$ 13.44일)와 평균 몸무게(4.51 $\pm$0.29 vs. 6.62 $\pm$0.27 kg)를 제외한 술 전 변수들은 차이가 없었다. 결과: A군에서 연속적으로 측정한 동맥혈 산소 포화도가 통계학적으로 유의하게 낮게 나타났다. 병원 내 사망률은 각각 $25\%$와 $19\%$였다. 추적관찰 기간동안 A군에서 2명, B군에서 5명의 만기 사망이 있었다. 결론: 본 연구에서는 유아기의 환아들에서도, 수술 위험성이 나이가 든 환아들과 비교하여 비슷하여 양방향성 상대정맥-폐동맥 단락술이 후에 시행될 폰탄수술의 위험성을 높일 수 있는 반복적인 고식적 수술을 피할 수 있는 수술방법이라고 생각한다. 하지만, 폐동맥고혈압이나 Heterotaxia 증후군 등이 동반된 고위험군 환아에서는 다른 고식적 수술을 고려하는 것이 좋을 것으로 생각한다.