• 대한기계학회논문집B
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• 제31권4호
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• pp.313-319
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• 2007

The effect of capillary cross-section geometry on evaporation is investigated in terms of the meniscus shape, evaporation rate and evaporation-induced flow for circular, square and rectangular cross-sectional capillaries. The shapes of water and ethanol menisci are not much different from each other in square and rectangular capillaries even though the surface tension of water is much larger than that of ethanol. On the other hand, the shapes of water and ethanol menisci are very different from each other in circular capillary. The averaged evaporation fluxes in circular and rectangular capillaries are measured by tracking the meniscus position. At a given position, the averaged evaporation flux in rectangular capillaries is much larger than that in circular capillary with comparable hydraulic diameter. The flow near the evaporating meniscus is also measured using micro-PIV, so that the rotating vortex motion is observed near the evaporating ethanol and methanol menisci except for the case of methanol meniscus in rectangular capillary. This difference is considered to be due to the existence of corner menisci at the four comers.

• 한국가시화정보학회지
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• 제9권2호
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• pp.48-53
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• 2011

The shape of nozzle cross-section plays an important role in stabilizing electrospray jet. The angle of contact line is governed based on the famous Young-Laplace equation. Compared to a round nozzle that has a constant curvature along the orifice, the square nozzle has four square corner edges and four straight edges that hold the meniscus in a different manner and is of interest in this study. By utilizing both square and round capillary nozzle, we examine the effect of nozzle shape in electrohydrodynamic jetting. The ejections were recorded with a high speed camera and analyzed to examine the jetting repeatability based on dynamic movement of meniscus. The result suggests that if the corner edges are not sharp, then its effect on repeatability is also limited.

• 대한정형외과스포츠의학회지
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• 제1권2호
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• pp.118-123
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• 2002

목적: 저자들은반월상연골후내각부에사용되던기존의inside-out 의수술수기를변형하여수직봉합이가능하면서충분한고정력을얻을수있는수술수기를보고하는바이다. 수술수기: 관절경을전외측도달법으로위치시키고봉합용갈고리를전내측도달법으로위치시켜봉합용갈고리를돌려서내측반월상연골후내각부에파열된부분의내측의대퇴골쪽표면에서경골쪽표면으로통과시킨다. 갈고리내로PDS $\#0$을통과시킨후봉합용갈고리를빼내고전내측도달법입구로PDS$\#0$의양끝을뽑아낸다. 전내측도달법입구에관절경을위치시킨후전외측도달법입구로Zone specific cannula를통과시켜반월상연골파열면의경골면에위치시키고저자가고안한Looped Needle을통과시킨 후 경골면의PDS $\#0$을Looped Needle의loop 사이를통과시킨후관절밖으로빼낸다.대퇴골면의PDS $\#0$도같은방법으로관절밖으로빼낸다. 2개의PDS 봉합사가나온입구근처에약1cm가량의incision 을넣고PDS 봉합사사이에연부조직이끼지않음을확인하고결찰을시행한다. 고찰: 변형된inside-out 봉합술은기존의inside-out 봉합술에비해수술시간의지연이있을수있으나, 수직봉합을할수있고견고한고정력을얻을수있으며해부학적인정복으로파열부위의접촉면을증가시켜후내각반월상연골의파열을봉합하는우수한방법으로판단되어보고하는바이다.

• Journal of Mechanical Science and Technology
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• 제20권5호
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• pp.710-716
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• 2006

Micro-PIV system with a high speed CCD camera is used to measure the flow field near the advancing meniscus of a water slug in microchannels. Image shifting technique combined with meniscus detecting technique is proposed to measure the relative velocity of the liquid near the meniscus in a moving reference frame. The proposed method is applied to an advancing front of a slug in microchannels with rectangular cross section. In the case of hydrophilic channel, strong flow from the center to the side wall along the meniscus occurs, while in the case of the hydrophobic channel, the fluid flows in the opposite direction. Further, the velocity near the side wall is higher than the center region velocity, exhibiting the characteristics of a strong shear-driven flow. This phenomenon is explained to be due to the existence of small gaps between the slug and the channel wall at each capillary corner so that the gas flows through the gaps inducing high shear on the slug surface. Simulation of the shape of a static droplet inside a cubic cell obtained by using the Surface Evolver program is supportive of the existence of the gap at the rectangular capillary corners. The flow fields in the circular capillary, in which no such gap exists, are also measured. The results show that a similar flow pattern to that of the hydrophilic rectangular capillary (i.e., center-to-wall flow) is always exhibited regardless of the wettability of the channel wall, which is also indicative of the validity of the above-mentioned assertion.

• 대한정형외과 초음파학회지
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• 제1권1호
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• pp.50-57
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• 2008

구조물에 대한 체계적 이해인 해부학과 그 역할에 대한 기능적 확인이라고 할 수 있는 신체 검진법은 슬관절을 진료하는 임상의로서 갖추어야 할 가장 기본적인 소양이라고 할 수 있다. 본문에서는 슬관절의 골성 구조, 반월상 연골, 전후방 십자 인대, 내외측 측부 인대, 근육, 내측 및 외측 삼층 구조 개념, 전후방 해부학, 슬관절 주위 점액낭에 대한 해부학 및 반월상 연골, 내외측 측부 인대, 전방 십자 인대, 후방 십자 인대 및 후측방 구조물에 대한 신체 검사에 대해 기술하였다. 해부학 및 신체 검진법에 대한 개념적이고 체계적인 이해는 슬관절을 치료하는 임상의에게 나침반과 등대와 같은 역할을 할 것이다.

• 대한관절경학회지
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• 제10권2호
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• pp.184-186
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• 2006

슬관절 외측 측부 인대 단독 손상은 인대 부착부의 견열 골절, 또는 인대 실질 내 파열로 인한 것으로 보고되고 있다. 외측 측부 인대의 견열 골절의 치료는 anchor나 staple을 이용한 일차 봉합을 주로 시행하였다. 반월상 연골의 수복을 위하여 사용된 staple의 이완(loosening)이나 이동은 보고된 바 있으나, 외측 측부 인대의 복원을 위한 staple이 이완되거나, 이동한 예는 아직 보고되지 않았다. 저자들은 외측 측부 인대 복원을 위하여 사용된 staple이 관절 내로 이동한 예를 경험하여 이를 보고하고자 한다.