• Transactions of the Korean Society of Mechanical Engineers B
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• v.31 no.4
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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.

• Journal of the Korean Society of Visualization
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• v.9 no.2
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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.

• Journal of Korean Orthopaedic Sports Medicine
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• v.1 no.2
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• pp.118-123
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• 2002

Purpose: To report modified technique of inside-out suture in repair of tear of postero medial corner of medial meniscus. Operative technique: Arthroscope is placed through anterolateral portal. Suture hook is delivered through anteromedial portal. By rotating the suture hook, it penetrates the inner portion of the torn meniscus from femoral surface to tibial surface of the meniscus for vertically oriented suture. A PDS suture is delivered through the lumen of suture hook, and the suture hook is withdrawn. The both ends of the suture are retrieved through anteromedial portal by a retriever, either grasper or crochet hook.A Zone-specific cannula is positioned below the inferior surface of the meniscus through anterolateral portal. The Looped Needle designed by the authors is delivered through the lumen of the Zone-specific cannula. The suture end of the tibial surface is placed in the loop of the Looped Needle and pulled out to the surface of posteromedial joint line. The suture end of the femoral surface is pulled out in same manner. A transverse skin incision of 1cm size is made adjacent to pulled out suture and the suture is tied. Discussion: Even though modified inside-out suture technique requires longer operation time than conventional inside-out technique, it provides vertically oriented suture and good tissue coaptation. The authors recommend this modified inside-out suture technique to be good alternative in repairing tear of the posteromedial corner of medial meniscus.

• Journal of Mechanical Science and Technology
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• v.20 no.5
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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.

• The Journal of Korean Orthopaedic Ultrasound Society
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• v.1 no.1
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• pp.50-57
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• 2008

The anatomy which is the systemic understanding of a structure and the physical examinations which is the functional assessment of its role comprise the fundamental capability for a clinician providing medial care to the knee. This article provides the basic anatomy of the bones, meniscus, anterior and posterior cruciate ligaments, medial and lateral collateral ligaments, muscles, medial and lateral 3 layer concept, anterior and posterior aspect of the knee, bursae around the knee, and the physical examinations of the meniscus, medial and lateral collateral ligament, anterior and posterior cruciate ligament with posterolateral corner. The conceptual and systemic understanding of the anatomy and the physical examinations of the knee would be a compass or lighthouse for the physician providing medical care to the knee.

• Journal of the Korean Arthroscopy Society
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• v.10 no.2
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• pp.184-186
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• 2006

Isolated lateral collateral ligament injury has been reported as avulsion fracture of attachment site or intrasubstance tear. The treatment of avulsion fracture of lateral collateral ligament was primary repair with anchor or staple. There are some reports about loosening or migration of staple which used in repairing meniscus of knee. There is, however, no report about loosening or migration of staple which was used for lateral collateral ligament repair. We report a case of migrated staple that was used for lateral collateral ligament repair, which was migrated to intraarticular posterolateral corner of the knee.