다중절단수지의 재접합술

권순범,박지웅,조상헌,서형교,황종익 대한성형외과학회 2011 Archives of Plastic Surgery Vol.38 No.5

Purpose: The recent advances in microsurgical techniques and their refinement over the past decade have greatly expanded the indications for digital replantations and have enabled us to salvage severed fingers more often. Many studies have reported greater than 80% viability rates in replantation surgery with functional results. However, replantation of multi-level amputations still remain a challenging problem and the decision of whether or not to replant an amputated part is difficult even for an experienced reconstructive surgeon because the ultimate functional result is unpredictable. Methods: Between January of 2002 and May of 2008,we treated 10 multi-level amputated digits of 7 patients. After brachial plexus block, meticulous replantation procedure was performed under microscopic magnification. Postoperatively, hand elevation, heat lamp, drug therapy and hyperbaric oxygen therapy were applied with careful observation of digital circulation. Early rehabilitation protocol was performed for functional improvement. Results: Among the 19 amputated segments of 10digits, 16 segments survived completely without any complications. Overall survival rate was 84%. Complete necrosis of one finger tip segment and partial necrosis of two distal amputated segments developed and subsequent surgical interventions such as groin flap, local advancement flap and skin graft were performed. The overall result was functionally and aesthetically satisfactory. Conclusion: We experienced successful replantations of multi-level amputated digits. When we encounter a multi-level amputation, the key question is whether or not it is a contraindication to replantation. Despite the demand for skillful microsurgical technique and longer operative time, the authors’ results prove it is worth attempting replantations in multi-level amputation because of the superiority in aesthetic and functional results.

증기터빈 익렬유동에 관한 실험적 연구

권순범,윤의수,김병지 대한기계학회 1994 대한기계학회논문집 Vol.18 No.8

The rapid expansion or condensible gas such as moist air of steam gives rise to nonequilibrium condensation. As a result of irreversibility of condensation process in the supersonic cascade flow of low pressure steam turbine, the entropy of the flow is increased, and the efficiency of the turbine is decreased. In the present study, to investigate the flow of moist air in 2-dimensional cascade made as the configuration of the tip section of the last actual steam turbine moving blade, the static pressure at both sides of pressure and suction of blade are measured by static pressure taps and the distribution of Mach number on both surfaces of the blade are obtained by using the measured static pressure. Also, the flow field is visualized by a schlieren system. From the experimental results, the effects of the stagnation temperature and specific humidity on the flow properties in a 2-dimensional stationary cascade of a practical steam turbine blade are clearly identified.

정보시스템 프로젝트 계획 수립을 위한 XML 기반의 사례기반 추론 시스템 개발

권순범,김서형 한국경영정보학회 2002 한국경영정보학회 학술대회논문집 Vol.2002 No.-

조석의 주기를 고려한 해상 암굴착 공사의 경제성 분석 및 작업가능시간 산정 방법에 관한 연구

권순범,옥종호,이승현,Kwon, Soon-Boum,Ock, Jong-Ho,Lee, Seung-Hyun 한국건설관리학회 2007 건설관리 : 한국건설관리학회 학회지 Vol.8 No.5

해상에서 이루어지는 암굴착 공사는 평균해수면 이하를 기준으로 수중으로 설계가 되어 있다고 하더라도, 조석간만의 차가 심한 서해와 남해의 경우에는 조석의 주기에 따라 해수면 위로 작업면이 노출되는 동안 육상작업이 가능해진다. 이를 활용할 경우 수중 작업 시 작업자의 위험성 증대, 작업효율의 저하 및 공사비 증대에 관한 수중공사의 단점을 보완할 수 있는 하나의 대안이 될 수 있다. 그러나 작업해야할 암굴착면의 높이와 조석에 따라 변화하는 수면의 높이에 따라 작업면의 노출시간, 즉 작업가능시간이 변화하게 되며 이에 따라 공사비의 변화도 발생하게 된다. 따라서 본 연구에서는 해상 암굴착 공사를 수행할 때 수중 작업과 비교하여 조석간만의 차를 이용한 공사의 경제성을 분석하고, 작업가능시간을 산정하여 작업시간별 경제성을 분석할 수 있는 방법을 제시함으로써, 조석간만의 차를 이용한 해상 암굴착 공사방식의 적용가능성을 모색해 보고자한다. The rock excavation work on the sea is planned as underwater process if the elevation of the rock is lower than the M.S.L.(Mean Sea Level). However, in case of West and South sea which are largely different between the rise and fall of the tide, the earth work can be performed on the ground while the work surface is exposed above the sea according to the tide cycle. Thus, it may a good substitute to make up for shortcomings of underwater construction works such as safety problems of workers, loss of efficiency and increasement of construction costs. But the difference between the height of the rock excavation surface and the water surface changed by the tide makes the exposure time of work surface, that is the possible working hours be changed. Also, it may cause the changes of construction cost. Thus, this study analyzes the economical efficiency of the construction method using the difference between the rise and fall of the tide in comparison with the construction method which is performed under the sea, and it also suggests the way to analyze the economical working hours by estimating the possible working hours on the ground. We also try to find out the application possibility of the way like the rock excavation work on the sea using the difference between rise and fall of the tide.

다양한 형태의 정(배)수지의 흐름특성 비교

권순범,강준구,최일환,이선주 대한환경공학회 2003 대한환경공학회 학술발표논문집 Vol.2003 No.12

폴리머 폼의 비선형 인장거동을 모사하기 위한 기공이 고려된 손상 탄성 구성방정식

권순범,이제명 한국전산구조공학회 2018 한국전산구조공학회논문집 Vol.31 No.4

폴리머 폼은 다공성을 가장 큰 특징으로 하는 재료이기 때문에, 본 연구에서 비가역 열역학 관점을 기반으로 폴리머 폼의 기공 성장 및 합체를 고려한 손상 탄성 구성방정식을 개발하였으며, 개발된 구성방정식은 unilateral 손상의 효과를 고려하였다. 유한요소해석의 적용을 위해 상용 유한요소해석 프로그램인 ABAQUS의 사용자 서브루틴 UMAT을 이용하여 제안된 구성방정식을 수치적으로 구현하였다. 비선형 유한요소해석 결과와 폴리머 폼의 인장 시험 결과와 비교를 통해 제안된 손상 모델의 유효성을 검증하였으며, 제안된 구성방정식의 재료모델상수가 손상에 미치는 영향에 대해 분석하였다. This paper details the development of an isotropic elastic-damage constitutive model for polymeric foam based on irreversible thermodynamics to consider the growth and coalescence of voids. The constitutive equations describe the material behavior sustaining unilateral damage. To facilitate finite element analysis, the material properties for specific types of polymeric foams are applied to the developed model; the model is then implemented in ABAQUS as a user-defined material subroutine. To validate the developed damage model, the simulated results are compared to the results of a series of tensile tests on various polymeric foams. The proposed damage model can be utilized to further research on continuum damage mechanics and finite element analysis of polymeric foams in computational engineering.

서비스 비즈니스모델 기반의 태양광사업 : 에스에너지의 JCPenney 백화점 사례

권순범,임종화,김봉기 한국경영정보학회 2014 한국경영정보학회 학술대회논문집 Vol.2014 No.1

에스에너지는 2012년 미국 캘리포니아 지역에 있는 JCPenny 백화점의 직영점 2개 점포에 태양광 발전시설을 건설하여 태양광 전기를 공급하는 프로젝트를 시작하였다. 2013년 6월 2개 점포(Manteca: 489kW, Antioch: 566kW)에 전기공급을 시작하였고, 앞으로 10개 점포에 추가 공급을 계획하고 있다. JCPenney 백화점 프로젝트는 에스에너지에게 다음과 같은 의미가 있다. 첫째, 현지 전력회사의 송배 전망을 이용하지 않고 최종사용자(end-user)에게 직접 전기판매를 구현한 에스에너지 최초의 서비스 비즈니스모델(BM: Business Model)의 구현이다. 둘째, 건설-리스(운영)-회수 모델을 신재생에너지 사업 에 적용하여 사용자에게는 초기부담을 덜어주고 사업자는 임대수입으로 안정적인 현금흐름을 확보할 수 있는 수익구조를 구현하였다. 셋째, 미국정부의 신재생에너지 지원정책인 가속감가상각(MACRS) 과 투자세액공제(ITC) 제도를 활용하여 초기 사업성을 확보하여 투자금 모집에 성공하였다. 넷째, 서 비스 비즈니스모델에 기반한 사업의 수행으로 새로운 역량을 확보하였고, 이러한 역량을 기반으로 태양광모듈 제조와 설치 사업에서 최종사용자에게 에너지서비스를 제공하는 사업으로 확장하는 계기 가 되었다. 본 사례는 에스에너지가 태양광산업의 격랑을 극복하는 과정과 JCPenney 백화점 프로젝 트를 통해서 서비스 비즈니스모델의 구현과 비즈니스모델 혁신역량을 어떻게 키웠는지 보여준다.

[피신청인] 언론이 자유언론에서 책임언론으로 거듭나는 데 언론중재는 일익을 담당

권순범 언론중재위원회 2001 言論仲裁 Vol.78 No.-

Numerical analysis for the coating thickness prediction in continuous hot-dip galvanizing

권순범,권영두,이성진,신승영,Geun-Young Kim 대한기계학회 2009 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.23 No.12

Gas wiping is a decisive operation in the hot-dip galvanizing process. Especially, it has a crucial influence on the thickness and uniformity of coating film, but may be subsequently responsible for splashing. To date, the number of fundamental studies on the jet structure impinging on a vertical moving strip for various nozzle systems has not been sufficient to draw any meaningful conclusion. In this connection, at first, to confirm the validation of numerical analysis, the impinging jet pressure on the surface of a vertical strip by experiment is compared with the results by numerical analysis. Next, after confirming for the superiority of a constant expansion rate nozzle in splashing, the relationship between the stagnation pressure and the impinging jet pressure distribution issuing from the nozzle system of constant expansion rate is investigated. Finally, by using the calculated wall shear stress, the relationships among the coating thickness, strip speed and nozzle stagnation pressures are clarified. It is found that the impinging wall pressure for the case of constant expansion rate nozzle is more favorable for the problem of splashing to the case of the conventional one. Furthermore, from the point of view of energy conservation, it is advisable to use a constant expansion rate nozzle as a gas-wiping nozzle.

A study on the flow with nonequilibrium condensation in a minimum length nozzle

권순범,이성진,신승영,김성하 대한기계학회 2009 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.23 No.6

As recognized previously, a minimum-length nozzle has the smallest possible throat-to-exit length that is still capable of maintaining uniform supersonic flow at the nozzle exit. In the present study, for the flow of moist air through a nearly minimum-length nozzle designed by the method of characteristics, the effects of nonequilibrium condensation on the uniformity of flow properties, the momentum efflux, and the flow distortion at the nozzle exit plane are discussed by experiment and numerical analysis of a third-order Total Variation Diminishing (TVD) finite difference scheme. The onset and zone of nonequilibrium condensation in a minimum-length nozzle are quite different from those of a general convergent-divergent supersonic nozzle. We know that the uniformity of flow properties at the nozzle exit with regard to the flow with nonequilibrium condensation in a minimum-length nozzle cannot be guaranteed. On the other hand, owing to the positions of the onset of condensation at the incident region of expansion waves from the sharp corner just downstream of the nozzle throat, the deceleration gradient and magnitude of heat released from the process of nonequilibrium condensation to the surrounding of φ0=60% are greater than those of φ0=70% in the case of T0=290K. Furthermore, it has been determined that the decrease in efflux of momentum from the nozzle exit for the stagnation relative humidity of φ0=70%(T0=290K), which corresponds to the case with nonequilibrium condensation shock, is 6.8% smaller than that of isentropic expansion.