LOD 시스템 개발과 공학실험과목의 콘텐츠 제작

서상호,노형운,조민태,양수봉,Suh Sang-Ho,Roh Hyung-Woon,Cho Min-Tae,Yang Soo-Bong 한국공학교육학회 2000 공학교육연구 Vol.3 No.1

미래 지향적 공학교육은 기본이론을 철저하게 습득시키고 다양한 실험교육을 통해 창의성을 함양하며, 실제 사회와 연계된 실용성에 중점을 두어야 한다. 본 논문에서는 교육 패러다임의 변화에 발맞추어 LOD 시스템의 개발방향을 제시하고 공학실험과목의 콘텐츠를 제작하는 방법을 소개하였다. Internet 기반의 LOD시스템을 구축할 때 코스웨어 개발에 필요한 고려사항과 설계방안을 검토하여 이를 공학실험과목의 콘텐츠 제작시 적용하였다. 본 연구의 결과는 실험교과내용을 충실하게 설명하고, 공학실험에 필요한 학습보조자료와 멀티미디어 자료를 제공하여, 학생들의 학습증진에 기여할 뿐만 아니라 대학의 미래상을 예측하고 이를 구현함으로서 대학의 나가야 할 방향을 제시할 수 있을 것이다. Future education for engineering should focus on the teaching of fundamentals, creativity cultivated through various experimental educational programs, and industry-related practices. This study presents the development of the LOD system and a contents production of the experimental courses in engineering in accordance with paradigm change. In this study, considerations and design plan for developing LOD system are discussed and they are applied to the contents production of the experimental course in engineering. The results of this study help to teach the experimental courses completely, providing the course supplements and the multimedia data required in the experimental courses, and to promote and conduct the student's projects. This study can also anticipate an image of the future university and present the direction where the university should follow in the future.

혈액유동이 혈관내피세포의 형태변화에 미치는 영향

서상호,유상신,민병구,장준근,Suh, Sang-Ho,Yoo, Sang-Sin,Min, Byung-Gu,Chang, Jun-Keun 대한기계학회 1998 大韓機械學會論文集B Vol.22 No.11

The objective of this study is to investigate the effects of the hemodynamics on the morphological changes of the human endothelial cells due to the blood flow by in vitro experiment and computer simulation. The morphological changes of the endothelial cells due to the t10w shear stress were observed in the laminar t10w chamber as a function of the exposure time. The observed shapes of the endothelial cells are used to the model shapes of the endothelial cells for numerical study and the pressure and the wall shear stress variations around the endothelial cells are calculated from the numerical results. The endothelial cells elongate along the t10w direction and lessen their heights in the flow field to reduce the pressure and the wall shear stress on the surface.

이중 분지관내 혈액 및 혈액대용유체의 3차원 유동해석

서상호,유상신,노형운,Suh, Sang-Ho,Yoo, Sang-Sin,Roh, Hyung-Woon 대한의용생체공학회 1997 의공학회지 Vol.18 No.2

The three-dimensional flow analysis using the finite volume method is presented to compare the steady flow characteristics of blood with those of blood substitutes such as water and aqueous polymer solution in an idealized double branching model. The model is used to simlllate the region of the abdominal aorta near the celiac and superior mesenteric branches. Apparent viscosities of blood and the aqueous Separan solution are represented as a function of shear rate by the Carreau model, Water and aqueoiu Separan AP-273 500wppm solution are frequently used as blood substitutes in vitro experiments. Water is a typical Newtonian fluid and blood and Separan solution are non-Newtonian fluids. Flow phenomena such as velocity distribution, pressure variation and wall shear stress distribution of water, blood and polymer solution are quite different due to differences of the rheological characteristics of fluids. Flow phenomena of polymer solution are qualitatively similar to those of blood but the phenomena of water are quite different from those of blood and polymer solution. It is recommended that a lion-Newtonian fluid which exhibits very similar rheological behavior to blood be used in vitro experiments. A non-Newtonian fluid whose rheological characteristics are very similar to those of blood should be used to obtain the meaninylll hemodynamic data for blood flow in vitro experiment and by numerical analysis

접선류 임펠러형 수도미터의 노즐직경이 성능특성에 미치는 영향

서상호,이병호,조민태,노형운,Suh, Sang-Ho,Lee, Byung-Ho,Cho, Min-Tae,Roh, Hyung-Woon 한국유체기계학회 1999 한국유체기계학회 논문집 Vol.2 No.3

In this study the effects of nozzle diameter on the performance characteristics for the tangential impeller-type water meter are studied experimentally. The nozzle is cut along the tangential direction of the inner case in the water meter. The nozzle shape is round and the number of nozzles used for the experimental study are 8. The performance characteristics are discussed for various nozzle diameters such as 3.1, 3.3, 3.5, 4.0, 4.5 and 5.0 mm. Among the tangential impeller-type water meters, the water meter with the nozzle diameter of 5.0 mm shows the least pressure loss and the instrumental error compared to the Korean Standards.

수치시뮬레이션을 이용한 흡입식 슬러지 수집기의 유동해석

서상호,노형운,변종훈,Suh, Sang-Ho,Roh, Hyung-Woon,Byun, Jong-Youn 한국유체기계학회 2006 한국유체기계학회 논문집 Vol.9 No.5

Sedimentation phenomenon of suspended solids occurs by the gravitational force. Pollution particles are separated from slowly flowing waste water in clarifier. Recently, the sludge suction collector is Preferred rather than the scraper type sludge collector due to the enhancement of the clarifier efficiency. The sludge suction collector is usually operated by the user's experiences without any scientific and/or technical consideration. To evaluate the performance of sludge suction collector, the three dimensional numerical simulation was conducted by the finite volume method. To analyze the performance, the velocity vectors and the suction flow rates of the orifices were investigated. The result showed that each suction flow rate through out the collector was equivalent in the sludge suction collector and the efficiency of suction collector was good to remove high concentrated sludge in clarifier.

심장 일의 측정을 위한 수학적 모델링

서상호(Sang-Ho Suh),Yalin Kaptan,노형운(Hyung-Woon Roh),송지운(Ji-Hoon Song) 대한기계학회 2012 大韓機械學會論文集B Vol.36 No.2

심장 일을 계산하여 혈관질환을 진단하는 방법이 새롭게 대두되고 있다. 이 연구의 목적은 혈관내의 두 지점에서 압력을 측정하여 점도 모델로부터 압력 펄스 및 심장 일을 구하는 수학적 모델을 개발하는 것이다. 심장 일을 측정하기 위해서 커프로부터 구한 혈압과 펄스파에 대한 의료 정보를 활용하였다. 본 연구의 목적은 혈관 내 두 측정점 사이의 펄스파를 이용하여 심장 일을 구하기 위한 수학적 모델의 개발이다. 심장 일은 Casson 및 Hershel-Bulkery 점도모델과 Windkessel 모델을 이용하여 구하였다. Casson 점도 모델과 Hershel-Bulkley 점도 모델을 이용하여 근위부에서의 컴플라이언스 값은 차이가 없으나 원위부에서 값은 큰 차이가 나타났다. Evaluation of the heart work is starting to emerge as a new diagnostic tool for arterial diseases. The aim of this study is to develop a mathematical model for the estimation of heart work utilizing the pulse waves between two points of a vessel. In order to calculate heart work, medical data such as blood pressure waveforms (which are measured using a cuff) are utilized. The heart work is calculated by employing the modified Windkessel model together with the viscosity models of Casson or Herschel-Bulkely (H-B). The results indicate that the compliance values at the proximal and distal locations differ for the Casson and H-B models.

배수용 수중펌프의 비상 대응 운전모드 개발

서상호(Sang-Ho Suh),송광철(Kwang Chul Song),송경희(Kyung Hee Song) 한국유체기계학회 2021 한국유체기계학회 학술대회 논문집 Vol.2021 No.12

심장 일의 측정을 위한 수학적 모델링

서상호(Sang-Ho Suh),Yalin Kaptan,노형운(Hyung-Woon Roh),송지운(Ji-Hoon Song) 대한기계학회 2011 대한기계학회 춘추학술대회 Vol.2011 No.4

심장 일을 계산하여 혈관질환을 진단하는 방법이 새롭게 대두되고 있다. 이 연구의 목적은 혈관내의 두 지점에서 압력을 측정하여 점도 모델로부터 압력 펄스 및 심장 일을 구하는 수학적 모델을 개발하는 것이다. 심장 일을 측정하기 위해서 커프로부터 구한 혈압과 펄스파에 대한 의료 데이터를 활용하였다. 심장 일은 Casson 및 Hershel-Bulkery 점도모델과 Windkessel 모델을 이용하여 구하였다. Evaluating the heart work is starting to emerge as a new diagnostic tool for arterial diseases. The aim of this study is to develop a mathematical model for the estimation of heart work by utilizing the pulse waves between two points of a vessel. In order to calculate heart work, medical data such as blood pressure waveforms which are measured by using a cuff are utilized. For this purpose, the modified Windkessel model is used with the viscosity models of Casson and Hershel-Bulkely.

관상동맥의 기하학적 형상변화에 따른 동맥경화 위험도

서상호(Sang-Ho Suh),박준길(Jun-Gil Park),노형운(Hyung-Woon Roh),이병권(Byung-Kwon Lee),권혁문(Hyuck-Moon Kwon) 대한기계학회 2010 大韓機械學會論文集B Vol.34 No.10

박동유동조건에서 관상동맥 내의 유동특성과 혈류역학적 인자 분포를 선행연구에서 수행하여 혈류역학이 관상동맥 내의 협착현상과 연관관계가 있음을 밝혔다. 동맥경화증의 호발부위인 관상동맥 분지부에서 혈류역학적 변수를 분석하여 동맥경화증의 발생기전을 규명하는 것이 본 연구의 목적이다. 동맥경화증에 의한 협착현상은 혈액과 혈관벽 사이의 생화학 반응뿐 아니라 유동박리나 벽전단응력과 같은 혈류역학적 인자와도 관계 있음을 확인하였다. 관상동맥 분지부의 분지각이 증가할수록 분지부 단면에서의 재순환영역의 크기가 증가하고 교란유동이 발생하게 된다. 이 재순환영역이 관상동맥에서 동맥경화의 시작점으로 의심되는 영역이라 할 수 있다. A previous study showed that hemodynamics is correlated with stenosis in the coronary artery. The flow characteristics and the distributions of the hemodynamic wall parameters in the coronary artery are investigated under physiological flow condition. The present study also aims to establish the mechanism of the generation of atherosclerosis by analyzing the hemodynamic variables in the coronary artery where atherosclerosis frequently occurs. The stenosis phenomena due to atherosclerosis are related to not only the biochemical reaction between blood and blood vessels but also the hemodynamic factors sush as flow separation and oscillatory wall shear stress. As the bifurcated angle increases, the size of the recirculation area that appears in the cross section increases and disturbed flow is observed in this area. We speculate that this area is the starting point of atherosclerosis in the coronary artery.

동맥경화증의 발생에 관한 혈류역학적 가설들에 대한 비교연구

서상호(Sang-Ho Suh),조민태(Min-Tae Cho),노형운(Hyung-Woon Roh),권혁문(Hyuck Moon Kwon) 대한기계학회 2003 대한기계학회 춘추학술대회 Vol.2003 No.4

Atherosclerosis, which is a degenerate disease, is believed to occur in the vascular system due to<br/> deposition of cholesterol and low density lipoprotein(LDL) or thrombosis on the blood vessel.<br/> Atherosclerosis narrows arterial lumen, which is known as stenosis phenomenon of blood vessel.<br/> Pathogenesis of atherosclerosis is thought to occur mainly by aging. Restenosis phenomenon is<br/> observed in the same site of insertion of a stent and balloon angioplasty after treatment of<br/> interventional theraphy. Several hypothetical theories related to the generation of atherosclerosis have<br/> been reported: high shear stress theory, low shear stress theory, high shear stress gradient theory, flow<br/> separation and turbulence theory and high pressure theory. However, no one theory clearly explains the<br/> causes of atherosclerosis. In the present study the generation of atherosclerosis in the left coronary<br/> artery is investigated. The hypotheses are verified by using the computer simulation.