임계 오리피스를 통과한 입자의 운동특성과 입자 빔에 관한 수치적 연구

안진홍,안강호,Ahn, Jin-Hong,Ahn, Kang-Ho 대한기계학회 1999 大韓機械學會論文集B Vol.23 No.10

Particle motion through a disk type critical orifice placed in a 3.0cm diameter chamber has been studied numerically. In the simulation, the velocity field is solved using Pantankar's SIMPLER algorithm for the compressible flow and convergence of the computation is confirmed if the mass source at each control volume is smaller than $10^{-7}$. The particle motion in the flow field is solved in Lagrangian method. The particle trajectories showed that the particles injected away from the center line are expanded rapidly. At lower pressures, this expansion phenomena are more dominant. At lower pressures, the clear difference in particle and air speed is showed all the way down to the exit plan. It was found that particles with Stokes number of ca.2.5 tend to focus close to the center line very well except the particles travelling near the wall. However, particles with Stokes number greater than ca.2.5 show a tendency to cross the center line.

Open Box형 강재빔을 이용한 중앙분리대 형식의 개발

안진홍,박창민,최진성,김기환,최현호 한국도로학회 2009 한국도로학회 학술대회 발표논문 초록집 Vol.2009 No.11

특집 : 공업용(산업용) 클린룸의 최신 기술 - 클린룸 환경에서 오염입자 측정 방법

안진홍,강기태,권용택,An, Jin-Hong,Gang, Gi-Tae,Gwon, Yong-Taek 한국공기청정협회 2012 空氣淸淨技術 Vol.25 No.4

해상풍력 발전단지의 전력망 연계방식에 따른고장전류 분석

안진홍,김일환 한국전기전자학회 2020 전기전자학회논문지 Vol.24 No.3

The installation cost or the magnitude of the fault current varies depending on the grid connection method of theoffshore wind farm. Therefore, there is a need for an efficient power grid connection method considering the capacity andlocation of the complex. In particular, most power cables in offshore wind farms use 3-core considering cost andefficiency. In the event of a failure such as a short circuit, the entire cable must be replaced, which can lead tosignificant losses in terms of cost, considering repair costs and turbine downtime. Therefore, in this paper, a radial, ring,and molding method is introduced into a 100 MW wind farm to be installed at Jeju offshore, and a three-phase shortcircuit failure is performed using a PSCAD/EMTDC program to perform computer analysis. I would like to propose asuitable power grid connection method. 해상풍력 발전단지의 전력망 연계방식에 따라 설치비용이나 고장전류의 크기가 달라진다. 그렇기 때문에 단지의 용량과위치 등을 고려한 효율적인 전력망 연계 방법이 필요하다. 특히 해상풍력 발전단지의 전력케이블은 대부분 비용 및 효율적인부분을 고려하여 3-core를 사용한다. 케이블 단락 같은 고장이 발생하면 케이블 전체를 교체해야 하므로 수리비용 및 터빈정지 기간을 고려하였을 때 비용적인 측면에서 상당한 손실이 발생할 수 있다. 따라서 본 논문에서는 제주해상에 설치될 100MW 풍력단지에 방사형, 링형, 성형 방식을 도입하여 이에 따른 3상 단락고장을 PSCAD/EMTDC 프로그램을 활용하여 컴퓨터 해석을 수행하고, 그 결과를 분석하여 모델 단지에 알맞은 전력망 연계방식을 제안하고자 한다.

제주도 내 회전교차로의 초기공사비 예측모델 개발

안진홍,이동욱,An, Jin-Hong,Lee, Dong Wook 대한토목학회 2014 대한토목학회논문집 Vol.34 No.4

최근 들어 교통사고 예방 및 교통지체 해소는 물론 도로이용자 교통편의를 제공하는 목적으로 회전교차로 설치공사가 많이 발주되고 있다. 그러나 회전교차로 공사에 대한 개략적인 공사비를 예측하는 기준이나 단가가 정립되어 있지 않을 뿐만 아니라, 회전교차로 공사 초기 단계에서의 공사비 예측에 관한 체계적인 연구가 미흡한 실정이다. 본 연구에서는 현재 제주도내에 설치된 회전교차로를 중심으로 공사현장의 여건을 고려한 공사 초기단계에서 회전교차로공사 개략공사비 산정 모델을 제시하고자 하였다. 본 연구에서는 제주도내 25개 회전교차로공사의 설계자료를 바탕으로 회귀분석을 통해 개략공사비 회귀방정식을 도출하였으며, 매우 예측의 정확도가 높은 것으로 분석되었다. 도출된 회귀방정식에 대해서 검증한 결과 회귀방정식을 통한 추정금액과 설계금액과의 오차율이 2.3%, 3.7%, 5.8%의 차이를 보임으로써 매우 예측의 정확도가 높은 것으로 분석되었다. Recently, there are many roundabouts installation works which are ordered to provide convenient transportation to road users as well as to eliminate traffic accidents and traffic delays. This study propose an approximate construction cost estimation model for early stages of roundabout construction. The model is designed considering the conditions of the early stage roundabout construction sites in Jeju. The regression equation of approximate construction cost was derived through regression analysis of 25 design data of roundabout construction in Jeju, and it was analyzed to have a high prediction accuracy. Finally, results verifies high prediction accuracy of the derived regression equation. Difference between the estimation cost and the design cost was only 2.3%, 3.7%, and 5.8% that verifies the high accuracy of the proposed approximate construction cost estimation model.

임계 오리피스를 통과한 입자의 운동 특성에 관한 수치적 연구 ( Numerical Study of Particle Motion Through a Critical Orifice )

안진홍,안강호 대한기계학회 1998 대한기계학회 춘추학술대회 Vol.- No.-

순환골재 추출입도 품질관리를 통한 순환 아스팔트 혼합물 성능향상 연구

안진홍,백종은,함상민,황성도,김영민 한국도로학회 2021 한국도로학회논문집 Vol.23 No.6

PURPOSES : The purpose of this study is to identify a gradation control method that minimizes the volatility of recycled aggregates to maintain the quality of reclaimed asphalt mixtures. METHODS : In this study, two types (0~13 and 0~10 mm) of recycled aggregate stockpiles with an extraction viscosity of 40,000 poise and a 19 mm hot asphalt mixture with virgin aggregates are used. The test methods are evaluated for plastic deformation resistance using the Hamburg wheel-tracking test and for low-temperature crack resistance using the dynamic modulus test. In the field, the performance is evaluated via an accelerated pavement test. RESULTS : The Hamburg wheel-tracking test shows good water resistance as well as less than 5 mm of deformation. The result of a dynamic modulus test at -5 °C shows a 92.9% low-temperature crack resistance as compared with that of the 19 mm dense grade hot-mix asphalt mixture. The result of the accelerated pavement test confirms that the performances of the 19 mm dense grade hot-mix asphalt mixture and reclaimed asphalt mixture are equal owing a 1.2 cm plastic deformation. CONCLUSIONS : By evaluating the plastic deformation resistance and crack resistance of the reclaimed asphalt mixture based on a stockpile gradation controlled at 0~10 mm via an indoor test, it is discovered that the plastic deformation resistance increases partially, whereas the crack resistance remains almost unchanged. The accelerated pavement test confirms that a performance equivalent to that of a 19 mm dense grade hot-mix asphalt mixture is achieved.

순환골재 추출입도 품질관리를 통한 순환 아스팔트 혼합물 성능향상 연구

안진홍,백종은,함상민,황성도,김영민 한국도로학회 2021 도로 : 도로학회지 Vol.23 No.3

PURPOSES : The purpose of this study is to identify a gradation control method that minimizes the volatility of recycled aggregates to maintain the quality of reclaimed asphalt mixtures. METHODS : In this study, two types (0~13 and 0~10 mm) of recycled aggregate stockpiles with an extraction viscosity of 40,000 poise and a 19 mm hot asphalt mixture with virgin aggregates are used. The test methods are evaluated for plastic deformation resistance using the Hamburg wheel-tracking test and for low-temperature crack resistance using the dynamic modulus test. In the field, the performance is evaluated via an accelerated pavement test. RESULTS : The Hamburg wheel-tracking test shows good water resistance as well as less than 5 mm of deformation. The result of a dynamic modulus test at -5 °C shows a 92.9% low-temperature crack resistance as compared with that of the 19 mm dense grade hot-mix asphalt mixture. The result of the accelerated pavement test confirms that the performances of the 19 mm dense grade hot-mix asphalt mixture and reclaimed asphalt mixture are equal owing a 1.2 cm plastic deformation. CONCLUSIONS : By evaluating the plastic deformation resistance and crack resistance of the reclaimed asphalt mixture based on a stockpile gradation controlled at 0~10 mm via an indoor test, it is discovered that the plastic deformation resistance increases partially, whereas the crack resistance remains almost unchanged. The accelerated pavement test confirms that a performance equivalent to that of a 19 mm dense grade hot-mix asphalt mixture is achieved.

소형위성 SAR 설계 기술

안진홍,정해원,김두환,김재현 대한전자공학회 2015 전자공학회지 Vol.42 No.4

복부 외상에 의한 위장관 손상

안진홍,소병준,이정균 圓光大學校 醫科學硏究所 1998 圓光醫科學 Vol.14 No.2

Purpose: We performed this study to evaluate certain factors and events contributing to the overall profile of the victim of abdominal trauma. Methods: 73 cases were analysed retrospectively who underwent operation for gastrointestinal injury from abdominal trauma at Wonkwang University Hospital from january 1995 to June 1998. Blunt injury account for 59 cases( 80%) and penetrating injury for 14 cases(20%) of the victims. Results: 1) The sex distribution was 62 males(85%) and 11 females(15%) with ratio of 5.6:1 and the age distribution revealed a high incidence in forths and fifth decades. 2) The causes of blunt trauma were traffic accidents (39 cases, 68.4%), violence (10 cases, 17.5%), and fall down (5cases, 8.8%),. The causes of penetrating trauma were stab injury (14 cases, 87.5%) and others (2 cases). 3) The clinical manifestations were abdominal tenderness (71.2%), abdominal pain(68.5%), rebound tenderness(52%), decreased bowel sound(38.3%), and abdominal distention(15%). 4) The plain films of abdomen showed free air under the diaphragm in 13 cases(17.8%) among the 73 cases of hollow viscus ruptures. Abdominal paracentesis was performed in 54 cases among 73 cases of hollow viscus rupture, of which 32 cases(59.3 %) revealed positive findings. 5) The peritoneal lavage was valuable in diagnosis, positive findings was 16 cases(84.2%) among 19 cases. 6) The injuried organs were small intestine (53 cases, 72.6%), colon(21cases, 28.8%). 7) The commonly associated extraabdominal injury were extremity fractures (38.2%), chest trauma(29.4%) and soft tissue injury(11.7%). 8) Postoperative complication were developed in 34 cases(46 %), which were intestinal obstruction (10 cases), pulmonary complication (7 cases), wound infection (6 cases), intraabdominal abscess (4 cases). 9) The overall mortality rate was 5.4 %. The causes of death were sepsis (2 cases), hypovolemic shock (1 case), and renal failure (1 case). The deaths and complications were increased by severe associated injuries(1 death in 28cases of 2 organ injury and 2 death in 11 casess of 3 or more organ injury) and diagnostic delay (1 death in 6cases of delayed operation). Conclusions: Repeated physical examinations, tests, and careful attention will be required in abdominal injury to avoid complicaton and mortality.