• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제16권3호
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• pp.190-194
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• 2013

Internal hernia (IH) is a rare cause of small bowel obstruction occurs when there is protrusion of an internal organ into a retroperitoneal fossa or a foramen in the abdominal cavity. IH can be presented with acute or chronic abdominal symptom and discovered by accident in operation field. However, various kinds of imaging modalities often do not provide the assistance to diagnose IH preoperatively, but computed tomography (CT) scan has a high diagnostic accuracy. We report a case of congenital IH in a 6-year-old boy who experienced life threatening shock. CT scan showed large amount of ascites, bowel wall thickening with poor or absent enhancement of the strangulated bowel segment. Surgical exploration was performed immediately and had to undergo over two meters excision of strangulated small bowel. To prevent the delay in the diagnosis of IH, we should early use of the CT scan and take urgent operation.

• Archives of Plastic Surgery
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• 제36권6호
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• pp.795-798
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• 2009

Purpose: The repair of complex chest wall defects presents a challenging problem for the reconstructive surgeon. In particular, a free flap is often required when the defect is large, in which case suitable recipient vessels must be found to insure revascularization. The authors report a case of persistent bronchopleural - cutaneous fistula developed after undergoing lobectomy for lung cancer. Methods: The defect area was repaired using a free vertical rectus abdominis muscle flap revascularized by microvascular anastomosis to the 6th intercostal pedicle. The flap obliterated the right chest cavity, closed the site of empyema drainage, and aided healing of a bronchopleural - cutaneous fistula. Results: The patient has remained healed for 14 months without any postoperative complications and recurrent infection or fistula. Conclusion: We suggest that a rectus abdominis musculocutaneus free flap and intercostal pedicle as a recipient could be a useful method for repair of chest defects.

• 한국추진공학회지
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• 제11권2호
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• pp.18-25
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• 2007

공동부 위에 설치된 슬롯판을 이용한 경사충격파와 난류 경계충의 간섭유동의 피동제어에 관한 수치적 연구가 수행되었다. 수치해석에서 얻어진 결과는 간섭전방에서 압축성 난류경계층 이론을 잘 따르고 있었으며, 또한 벽압력 분포와 쉴리렌 유동가시화와 같은 실험결과와 서로 잘 일치하고 있음이 확인되었다. 또한 슬롯의 위치와 개수, 슬롯의 각도 등 슬롯판의 다양한 형상변화가 간섭유동 특성에 미치는 영향이 관찰되었으며, 간섭유동 후방의 전압변화, 경계층 특성변화, 그리고 슬롯판을 통하여 공동부로 순환하는 질량유량의 변화 등이 서로 비교분석 되었다.

• 한국추진공학회지
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• 제17권3호
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• pp.9-14
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• 2013

수소를 연료로 사용하는 마하 5 스크램젯 엔진 모델에 대해 불어내기식 시험 설비를 사용해 연소 시험을 수행했다. 두 가지 모델 형상에 대해 각각 연료가 없는 경우와 두 가지 당량비로 연료를 공급한 경우를 시험했다. 모델 내부의 벽면 정압력을 측정해 시간에 대한 데이터와 시간 평균한 공간적 데이터 분포를 사용해 모델 내부의 유동과 연소 현상을 분석했다. 모델 길이가 짧은 경우는 두 가지 당량비 모두에서 초음속 연소가 일어났다. 모델 길이가 긴 경우는 낮은 당량비에서는 초음속 연소가, 높은 당량비에서는 열질식이 발생하면서 아음속 연소가 일어났다. 이 때 흡입구 불시동은 발생하지 않았다.

• Structural Engineering and Mechanics
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• 제60권2호
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• pp.337-350
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• 2016

Even though extensive researches have been performed for steam explosion due to their complex mechanisms and inherent uncertainties, establishment of severe accident management guidelines and strategies is one of state-of-the arts in nuclear industry. The goal of this research is primarily to examine effects of vessel failure modes and locations on nuclear facilities under typical steam explosion conditions. Both discrete and integrated models were employed from the viewpoint of structural integrity assessment of steel components and evaluation of the cracking and crushing in reinforced concrete structures. Thereafter, comparison of systematic analysis results was performed; despite the vessel failure modes were dominant, resulting maximum stresses at the all steel components were sufficiently lower than the corresponding yield strengths. Two failure criteria for the reinforced concrete structures such as the limiting failure ratio of concrete and the limiting strains for rebar and liner plate were satisfied under steam explosion conditions. Moreover, stresses of steel components and reinforced concrete structures were reduced with maximum difference of 12% when the integrated model was adopted comparing to those of discrete models.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1997년도 추계학술발표회논문집(1)
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• pp.713-718
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• 1997

In the TMI-2 accident, approximately twenty(20) tons of molten core material drained into the lower plenum. Early advanced light water reactor (LWR) designs assumed a lower head failure and incorporated various measures for ex-vessel accident mitigation. However, one of the major findings from the TMI-2 Vessel Investigation Project was that one part of the reactor lower head wall estimated to have attained a temperature of 1100$^{\circ}C$ for about 30 minutes has seemingly experienced a comparatively rapid cooldown with no major threat to the vessel integrity. In this regard, recent empirical and analytical studies have shifted interests to such in-vessel retention designs or strategies as reactor cavity flooding, in-vessel flooding and engineered gap cooling of the vessel Accurate thermohydrodynamic and creep deformation modeling and rupture prediction are the key to the success in developing practically useful in-vessel accident/risk management strategies. As an advanced in-vessel design concept, this work presents the COrium Attack Syndrome Immunization Structures (COASIS) that are being developed as prospective in-vessel retention devices for a next-generation LWR in concert with existing ex-vessel management measures. Both the engineered gap structures in-vessel (COASISI) and ex-vessel (COASISO) are demonstrated to maintain effective heat transfer geometry during molten core debris attack when applied to the Korean Standard Nuclear Power Plant(KSNPP) reactor. The likelihood of lower head creep rupture during a severe accident is found to be significantly suppressed by the COASIS options.

• 설비공학논문집
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• 제17권8호
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• pp.714-721
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• 2005

The water jet impingement cooling with boiling is one of the techniques to remove heat from high heat flux equipments. The configuration of surface roughness is one obvious condition of affecting the performance on heat transfer in nucleate boiling, The present study investigates the water jet impinging single-phase convection and nucleate boiling heat transfer for the effect of surface roughness to enhance the heat transfer in free surface and submerged jet. The distributions of the averaged wall temperature as well as the boiling curves are discussed. Jet velocities are varied from 0.65 to 1.7 m/s. Surface roughness by sand blast and sand paper varies from 0.3 to 2.51 ${\mu}m$ and cavity shapes on surface are semi-circle and v-shape, respectively The results showed that higher velocity of the jet caused the boiling incipience to be delayed more. The incipient boiling and heat transfer increase with increasing surface roughness due to a large number of cavities of uniform size.

• 설비공학논문집
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• 제18권12호
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• pp.971-976
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• 2006

The objectives of this paper are to study the characteristics of pool boiling heat transfer for enhanced tubes used in the evaporator of turbo chiller and to provide a guideline for optimum design of an evaporator using HFC134a. Three different enhanced tubes are tested at 4 different saturation temperatures. The wall super heated temperature difference ranges from $0.5^{\circ}C\;to\;3.5^{\circ}C$. The refrigerant, HFC134a evaporates on the outside of the tube while the chilled water flows inside the tube. This study provides experimental heat transfer coefficients for evaporation on the enhanced tubes. It is found that the turbo-II tube provides the highest heat transfer coefficient.

• 대한조선학회논문집
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• 제39권3호
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• pp.1-7
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• 2002

검증된 프로그램을 통하여 수축 팽창 운동에 대한 해석을 수행하였으며, 해석 결과 레이놀즈수가 작아지게($R_n{\fallingdotseq}1$) 되면 점성력을 이용한 추진이 효과적일 것으로 나타났고, 계산 결과를 꼭지점법과 비교하였다. 본 연구를 통하여 극도로 점성이 큰 지역에서 통상의 추진기로 추진이 불가능한 곳에서도 추진할 수 있는 새로운 추진 시스템을 제안하였으며, 이 시스템은 micro-hydro-machine의 추진 장치로 활용될 수 있으리라 기대된다.

• Archives of Pharmacal Research
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• 제23권5호
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• pp.482-487
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• 2000

The antitumor activity of Bifidobacterium breve K-110, and K-I11, and B. infantis K-525 was investigated. These Bifidobacterial cells and their cell wail preparations (WPG) significantly increased the survival rate of mice who had been intraperitoneally implanted with sarcoma 180 cells. Solid tumor growth was inhibited even when the sarcoma 180 cells were implanted into the groins of the mice. However, the Bifidobacterial cells did not show in vitro cytotoxicity against tumor cell lines. Cell kinetic studies revealed that these WPGs induced neutrophils, which were followed by macrophages, at the site of peritoneal injection. The WPGs directly activated these cells to inhibit the growth of tumor cells in vitro assays. Our results suggest that Bifidobacterial WPGs induce and activate nonspecific phagocytes in situ to reject growing tumor cells in the mouse peritoneal cavity.