• Journal of Yeungnam Medical Science
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• v.13 no.2
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• pp.234-242
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• 1996

Ten patients with a thoracolumbar spine fractures were treated with Kaneda internal fixation device through anterolateral approach during last 1 year. In all cases, spinal decompression, internal instrument fixation and hone fusion with rib were performed. No patient showed neurological deterioration after surgery and 6(60%) patients improved postoperatively with entering the next Frankel subgroup. Follwo-up patient evaluation showed the correction of the fracture deformity with good bony fusion, but 3 patient arc remained back pain. According to above results we concluded that anterolateral internal fixation combined with hone fusion using rib was good mechanical stability and decompression of protruding ventral bone fragments above conus medullaris level.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.369-374
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• 2011

To solve the combustion instability, especially chuffing phenomena, happened during development process of the drive-away motor that was required for cold launch system of missile, we tried various technical approaches and performed ground firing tests. The supplying content or method of ignition energy, generally that is deeply related with the chuffing phenomena, does not affect suppression of the chuffing, but the addition of 2% ZrC as a damping material is effective to suppress the chuffing. Therefore we could newly experience a special solution of the combustion instability in double base propellant.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.05a
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• pp.279-287
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• 2010

This paper surveys the recent research activities regarding dynamical modeling of high amplitude - high frequency thermo-acoustic instabilities occurring in gas-turbine engines, rockets, and etc, which are fundamental to actively control of such phenomena. For this, we introduces the reduced-order system modeling approaches, conducted after 1990s. Particularly, we deal with the grey-box approach, which determines the structure of the model based on physical rules and uses system's input-output data for estimating parameters of the model, and the black-box approach, which uses model structure without physics-based interpretation. At the end of the paper, we briefly discuss future directions and feasibilities of the research in this field.

• Journal of the Korean Society of Propulsion Engineers
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• v.16 no.4
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• pp.93-98
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• 2012

To solve the combustion instability, especially chuffing phenomena, happened during development process of a drive-away motor that was required for cold launch system of missile, various technical approaches have been performed through ground firing tests. The ignition energy or its supply system, generally closely related with the chuffing phenomena, does not affect suppression of the chuffing, but the increase of characteristic length($L^*$) as well as the addition of 2% ZrC as a damping material is effective to suppress the chuffing. Therefore we could have a typical experience on the combustion instability in double base propellant.

• Proceeding of EDISON Challenge
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• 2014.03a
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• pp.579-584
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• 2014

고속 열차의 속도가 점점 빨라짐에 따라 고속 열차 주행 시 발생하는 여러 공력적인 문제가 대두되고 있다. 그 중 고속 열차와 전력선을 이어주는 판토그래프에서의 소음 발생과 압상력 불안정 문제가 중요시 되어왔고 이에 대한 여러 선행연구가 진행되고 있다. 지금까지의 선행 연구는 원형, 사각형, 에어포일과 같이 기본적인 형상을 이용한 판토그래프 팬헤드의 최적 단면 형상을 찾는 데에 초점을 맞추고 있다. 본 연구는 이러한 주류의 접근 방식에서 벗어나 팬헤드에 구멍을 추가하여 그 효과를 보는 다양한 시도를 해보았고 구멍이 소음 발생과 압상력 불안정에 미치는 영향에 대하여 연구하였다.

• Journal of the Korean Society of Hazard Mitigation
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• v.7 no.4
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• pp.51-57
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• 2007

In this study, the flow in the spillway of Gun-nam flood control reservoir were simulated by using FLOW-3D model. The discharge in the overflow weir and flow stability in approach channel were investigated with the original design plan. The results show that the scale of spillway is unsuitable and the flow in approach channel is unstable. To solve this problem, therefore, the alternative design plan were formulated. The flow in the spillway were simulated with the alternative design plan. The results show that the scale of spillway is suitable and the flow in approach channel is stable.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• v.y2005m4
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• pp.274-280
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• 2005

Experimental investigations were carried out in an atmospheric pressure, optically accessible and laboratory-scale dump combustor. The objective of this study is to obtain the phase-resolved gas temperatures at different phases of the oscillating pressure cycle during unstable combustion. To see the effect of incomplete fuel-air mixing on phase-resolved temperature characteristics, CARS temperature measurements were performed. Results including phase-resolved averaged temperature, normalized standard deviation and temperature probability distribution functions (PDFs) were provided in this paper. It could be found that the profile of mean temperature showed the in-phase relationship with pressure cycle. Temperature PDFs give an insight on the flame behavior as well as NOx emission characteristics. These results would be expected to play an important role in better understanding of driving mechanisms and thermo-acoustic interactions.

• Journal of Advanced Navigation Technology
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• v.27 no.6
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• pp.888-896
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• 2023

When an aircraft is landing, it is expected that the aircraft will follow a specified approach procedure and then land at the airport. However, depending on the airport situation, neighbouring aircraft or the instructions of the air traffic controller, there can be a deviation from the specified approach. Detecting aircraft approach patterns is necessary for traffic flow and flight safety, and this paper suggests clustering techniques to identify aircraft patterns in the approach segment. The Gaussian Mixture Model (GMM), one of the machine learning techniques, is used to cluster the trajectories of aircraft, and ADS-B data from aircraft landing at the Gimhae airport in 2019 are used. The aircraft trajectories are clustered on the plane, and a total of 86 approach trajectory patterns are extracted using the centroid value of each cluster. Considering the correlation between the approach procedure pattern and overshoots, the distribution of overshoots is calculated.

• Journal of Veterinary Clinics
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• v.14 no.1
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• pp.126-130
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• 1997

10개월경의 그리폰 벤딘 수컷 강아지가 8개월경부터 점점 운동 실조 및 마비증상을 나타내어 머독대학 동물병원에 내원 하였다. 내원 했을 때 주변에 매우 민감한 반응과 경계를 늦추지 않았지만 호흡과 심박수 및 체온은 정상이었다. 일반 방사선 사진 및 척수조영사진(myelography)을 촬영하여 확인한 결과 환축추의 불안정에 따른 척수의 복측 압박을 확인할 수 있었다. 외과적 고정은 복측 접근을 통하여 2개의 키르크너 강선(Kirschner wire)과 자가골이식을 실시하였으며 8주동안 외부 고정을 하였다. 수술 후 5개월 동안 지켜본 결과 증상은 꾸준히 좋아졌으며 환축추 관절으 관절고정술(arthrodesis)은 완벽한 고정을 유지하고 있었다.

• Proceedings of the Korea Contents Association Conference
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• 2014.11a
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• pp.335-336
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• 2014

기존의 게임들이 젊은 연령대가 주를 이뤘다면, 2012년 출시된 '애니팡'은 게임을 부정적으로 바라보던 중장년층까지 흡수하면서 모바일게임의 대중화를 이뤄냈다. 하지만 그 인기가 현재까지 지속되지는 않는다. 그 이유로는 세 가지 정도로 요약되는데, 첫번째는 쉽게 질려 버릴 수 있는 단순한 게임방법이며, 둘째는 지인과의 순위경쟁의 긴장감을 지인이 떠나버리면서 잃어버렸기 때문이다. 마지막으로 세 번째는 게임의 불안정성과 더불어 스팸'하트'메시지의 스트레스이다. 반면에 성공요인으로는 첫 번째는 진입장벽의 용이성, 둘째는 친근감과 현대인들의 생활패턴에 접근 가능한 게임 환경, 셋째는 생활정서에 밀착된 '적절한 긴장감' 이라고 할 수 있다.