• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.21 no.3
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• pp.355-361
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• 2012

Though a micro pump is a crucial element in miniaturized bio-fluidic systems or drug delivery systems, it has some intrinsic disadvantages such as backward flow, pulsation of flow, low repeatability and producibility, and high cost. To overcome these limitation, a PZT disc actuated micro pump including a novel ring-shaped multi-flap check valve is introduced. To enhance the performance of the micro pump, the static behaviour of flap valve module and the micro fluidic behavior of fluids are numerically modelled and analyzed. As results of the numerical analysis, the optimal dimension and configuration of the ring-shaped multi flap valve are $1{\times}0.05$ mm and 2 (inlet side)${\times}1$ (outlet side) type. The obtained maximum flow rates and flow resolution are about 90 ml/min and 30 ${\mu}l$/stroke respectively.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.42
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• pp.38.1-38.7
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• 2020

Background: Lipomas are benign soft tissue neoplasms of mature adipose tissue commonly occurring in the trunk or extremities. But, intraoral lipomas are rare entities which may be only noticed during routine dental examinations. Especially intramuscular lipomas on the tongue have been reported very rarely. In this study, we report a case of intramuscular lipoma on tongue, with a review of the literature from 1978 to 2019, providing data on age, gender, location, presenting symptoms, size, surgical methods, and recurrence. Case presentation: A case of intramuscular lipoma occurring in tongue region in a 65-year-old male is reported. Surgical excision is the mainstay of treatment for the lesion. In order to decrease the deformity and discomfort after the excision, we tried to modify surgical technique using enveloped mucosal flap. This technique provided more comfortable healing procedure on the operative site without recurrence. Conclusion: This is a rare case of large intramuscular lipoma on tongue. Surgical excision with enveloped mucosal flap design was performed to diminish postoperative raw surface and discomfort and a 24-month follow-up showed excellent healing without any recurrence. A case of intramuscular lipoma on tongue and relevant literature reviews are presented in this study.

• Proceedings of the KSME Conference
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• 2001.06d
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• pp.1014-1019
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• 2001

A numerical investigation was performed to determine the effect of airfoil on the optimum flap height using NACA 00XX and 44XX airfoils. The six flaps which have 0.5% chord height difference were selected. A Navier-Stokes code, FLUENT, was used to calculate the flow field of the airfoil. The code was first tested as a benchmark by modelling flow around a NACA 4412 airfoil. Predictions of local pressure coefficients are found to be in good agreement with the result of the experimental result. For every NACA 00XX and 44XX airfoil, flap heights ranging from 0.0% to 2.5% chord were changed by 0.5% chord interval and their effects were also studied. Representative results from each case are presented graphically and discussed. It is concluded that this initial approach gives an idea for the future development of the wind turbine optimum design.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.596-599
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• 1997

In this study, the flow control system with shape memory alloy in jet engine inlet was suggested to adjust the shock boundary layer interact~on for supersonic flight system. It consisted of the flap with shape memory alloy, spar with steel, and fixing device with aluminum alloy. The advantages of itself are a simple configuration, a passive air circulation by using the flap deflection due to pressure difference, and no need to be required the auxiliary devices. Finite element analysis was conducted to predict the thenno-mechanical behavlor of the flap system with shape memory alloy. The user-defined subroutine UMAT was implemented with ABAQUS to accon~modate the thermo-mechanical constitutive relation of shape memory alloy.

• Journal of Ocean Engineering and Technology
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• v.14 no.2
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• pp.1-6
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• 2000

Wave energy absorption by a flap equipped with a harbor in a water of finite depth is studied. The wave potential is calculated by a hybrid integral equation consisting of Green integral equations associated with Rankine and Kelvin Green functions. The absorbed wave energy is calculated by both the near-field and far-field methods. The present methods can be used for the design of a flap-harbor wave energy absorber since the numerical results by the two methods are in good agreement.

• Archives of Craniofacial Surgery
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• v.13 no.1
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• pp.41-45
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• 2012

Purpose: Fibular osteocutaneous free flap is the procedure of choice for mandibular reconstruction. However, the anatomic consistency and the reliability of the skin paddle have been considered to be questionable and the utilization of the fibular osteocutaneous free flap can be challenging for the inexperienced surgeon. Preoperative computed tomography (CT) angiography can support revolutionary help with the operator design of the fibular osteocutaneous flap. The purpose of this article is to share the valuable experience of support with preoperative CT angiography. Methods: Three consecutive patients, who needed mandibular reconstruction, were treated with fibular osteocutaneous free flap. Each of the patients had undergone lower extremity CT angiography before the surgery. The CT angiographies were scrupulously investigated to calculate the locations and the tracts of the peroneal artery perforators. We compared the findings of the CT angiography with those of the real operation. Results: The information about the perforators was sufficiently matched with the findings of the operation. With the use of preoperative CT angiography, we were able to achieve confident performance during operation, shortening of operation time, and fine outcomes with a no flap failure. Conclusion: The CT angiography of lower extremity can provide reliable information of the perforators of the fibular osteocutaneous free flap.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.35 no.2
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• pp.101-105
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• 2009

Background: The vascularity of the peri-implant tissue is a very important parameter in establishment and maintenance of a healthy tissue after dental implant insertion. Objective: The purpose of this study was to compare the vascularity of the peri-implant mucosa between flap and flapless implant surgeries by using a canine mandible model. Study Design: In six mongrel dogs, bilateral, edentulated, flat alveolar ridges were created in the mandible. After 3 months of healing, two implants were placed in each side by either the flap or flapless procedures. After another healing period of 3 months, biopsies were obtained, prepared for light microscopy and exposed to morphometric measurements. Results: The supracrestal connective tissue lateral to the implant was found to be more richly vascularized in the flapless group than in the flap group. Conclusion: These results suggest that the flapless procedure may have an effect on increasing the vascularity of the peri-implant mucosa.

• Journal of computational fluids engineering
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• v.18 no.4
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• pp.41-46
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• 2013

The selection of the optimal position of the flap was performed in order to improve the aerodynamic performance during the take-off and landing processes of aircraft. For this, the existing airfoils of the main wing and flap are selected as the baseline model and the lift coefficients (cl) according to angle of attacks (AOA) were calculated with the change of the position of flap airfoil. The objective function was defined as the consideration of the maximum cl, lift to drag ratio and cl at certain AOA. Then, at 121 experimental points within $20mm{\times}20mm$ domain, two dimensional flow simulations with Spalart-Allmaras turbulence model were performed concerning the AOA from 0 to 15 degree. If the optimal position was located at the domain boundary, the domain moved to the optimal position. These processes were iterated until the position was included in the inside of the domain. From these processes, the flow separation at low AOA was removed and cl increased linearly comparing with that of the baseline model.

• Archives of Plastic Surgery
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• v.50 no.5
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• pp.523-528
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• 2023

The Gustilo IIIB tibiofibular fractures often result in long bone loss and extensive soft tissue defects. Reconstruction of these complex wounds is very challenging, especially when it includes long bone grafts, because the donor site is limited. We describe our experience using a set of chimeric ipsilateral vascularized fibula grafts with a thoracodorsal artery perforator free flap to reconstruct the traumatic tibia defects. A 66-year-old male suffered a severe comminuted tibia fracture and segmented fibula fracture with large soft tissue defects as a result of a traffic accident. He also had an open calcaneal fracture with soft tissue defects on the ipsilateral side. All the main vessels of the lower extremity were intact, and the cortical bone defect of the tibia was almost as large as the fractured fibula segment. We used an ipsilateral vascularized fibula graft to reconstruct the tibia and a thoracodorsal artery perforator flap to resurface the soft tissue, using the distal ends of peroneal vessels as named into sequential chimeric flaps. After 3 weeks, the calcaneal defect was reconstructed with second thoracodorsal artery perforator free flap. Reconstruction was successful and allowed rapid rehabilitation because of reduced donor site morbidity.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.35 no.9
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• pp.761-770
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• 2007

In this study, a swirl generator using delta wing was developed in order to simulate total pressure distortion and flow angle distortion. The delta wing was used for $65^{\circ}$-degree sweep back angle to satisfy the design performance for vortex core position, total pressure distortion(DC90) and swirl angle. To extend the swirling flow area, a $45^{\circ}$-degree vortex flap have applied to the delta wing. The swirl generator satisfied the design requirement of distortion coefficient in the flow distortion test to be applied to the simulation duct, and the performances of distortion for vortex core position and swirl angle using CFD(computational fluid dynamics) analysis results that was verified by flow distortion test results.