• 한국소음진동공학회논문집
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• 제14권6호
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• pp.486-494
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• 2004

This paper addresses the dynamic modeling and closed-loop eigenvibration analysis of composite rotating pretwisted fan blade modeled as non-uniform thin-walled beam with bi-convex cross-section fixed at the certain presetting angle and incorporating piezoelectric induced damping capabilities. The blade model incorporates non-classical features such as transverse shear, rotary inertia and includes the centrifugal and Coriolis force field. A velocity feedback control law relating the piezoelectiriccally induced transversal bending moment at the beam tip with the appropriately selected kinematical response quantity is used and the beneficial effects upon the closed loop eigenvibration of the blade are highlighted.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 1999년도 추계학술발표대회 논문집
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• pp.215-218
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• 1999

A general structural model, which is an extension of the Vlassov theory, is developed for the analysis of composite rotor blades with elastic couplings. A comprehensive analysis applicable to both thick-and thin-walled composite beams, which can have either open- or closed profile is formulated. The theory accounts for the effects of elastic couplings, shell wall thickness, and transverse shear deformations. A semi-complementary energy functional is used to account for the shear stress distribution in the shell wall. The bending and torsion related warpings and the shear correction factors are obtained in closed form as part of the analysis. The resulting first order shear deformation theory describes the beam kinematics in terms of the axial, flap and lag bending, flap and lag shear, torsion and torsion-warping deformations. The theory is validated against experimental results for various cross-section beams with elastic couplings.

• 대한두개안면성형외과학회지
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• 제20권6호
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• pp.408-411
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• 2019

Hairless scalp areas can occur due to trauma, tumors, or congenital disease. This aesthetically unpleasing condition can lead to psychosocial distress, and thin skin flaps may be prone to scarring. Treating the hairless scalp by simple excision is challenging because of skin tension. Tissue expanders are a good option for hairless scalp resurfacing. However, a single expansion may be inadequate to cover the entire defect. This report describes good results obtained using a serial resurfacing method involving re-expansion of the flap with a tissue expander to treat two patients with large lesions: one due to aplasia cutis congenital and another who underwent dermatofibrosarcoma protuberance resection. The results suggest that scalp resurfacing by serial tissue expansion using a tissue expander can be used for extensive lesions.

• EDISON SW 활용 경진대회 논문집
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• 제1회(2012년)
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• pp.13-16
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• 2012

본 논문에서는 항공기의 제어 안정성(Control Stability)과 조종성(Controllability), 그리고 기계 하중을 줄여 구조와 공기역학적인 안정성을 향상시키기 위해 고양력장치(High-lift Device)인 플랩에 탭이 추가된 익형을 설계하였다. 이 과정에서 한정된 해석자원 때문에 많은 설계조건을 해석하는데 어려움이 있었다. 이를 해결 하기위해 얇은 익형 해석(Thin Airfoil Theory)을 이용하여 지정된 설계구속조건을 통해 시위선을 지정하고 이를 바탕으로 두께를 부여하여 최종적인 익형을 설계하였다. EDISON CFD 2.0 Solver를 이용해 최종 설계한 익형의 성능을 해석하였다. 이를 바탕으로 플랩만 존재하는 익형에 비해 양력손실률이 15%이하로 감소하고, 힌지 모멘트가 최소인 공기역학적 익형을 산출하였다.

• Archives of Reconstructive Microsurgery
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• 제8권1호
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• pp.77-83
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• 1999

전북대학교병원 정형외과에서 1993년 8월부터 1997년 8월까지 족부 및 수부 손상 5례에 대하여 족 배 유리 피부판 이식술을 시행하고, 1999년 3월까지 최소 19개월부터 최장 67개월간 추시하여 다음과 같은 결과를 얻었다. 1. 나이별로는 9세부터 35세까지로 평균 23세 이었으며, 성별로는 전례가 남자이었으며, 족부에서 시행하였던 예가 4례, 수부에서 1례이었다. 2. 족부의 손상 원인은 교통사고 2례, 기계 사고 1례, 자전거 바퀴 사고 1례 이었으며, 수부에서는 교통사고에 의하여 전완부 요골의 개방성 골절이 동반되고 수부 배부의 다발성 신전 건 파열 및 피부 괴사에 의한 신전 건 노출 1례이었다. 3. 수여 동맥은 족 배 동맥 2례, 전 경골 동맥 1례, 후 경골 동맥 1례 그리고 척골 동맥이었으며, 수여 정맥은 족부 4례에서 2개 정맥을 문합하였으며, 5례(100%) 전례에서 성공하였다. 4. 추시 결과 유리 피판 이식술 후 외양(exterior)과 일상생활시 피부판이 손상되는 분쇄(maceration) 정도는 우수하였으나, 감각 회복 정토는 불량하였다. 5. 제공 부위인 족 배부는 유리 피판 이식술 3주 후 전층 식피술을 시행하여 완전 접착되었으며, 추시상 유병율없이 우수한 결과를 보였다.

• 대한기관식도과학회지
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• 제5권2호
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• pp.191-197
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• 1999

Background and Objective : Soft palate plays a great role in function of speech and swallowing. Ablation of tonsil cancer results in multi-demensional defect including soft palate in most cases and restoration of the postoperative oral cavity function is a continuing surgical challenge. Although a variety of techniques are available, radial forearm free flap has been known as an effective method for these defect, which offers a thin, pliable, and relatively hairless skin, and a long vascular pedicle. The aim of the present study is to report the speech and swallowing function test results of our 5 consecutive radial forearm free flaps used for tonsil cancers. Materials and Methods : We reviewed the medical records of 5 patients who were offered intraoral reconstruction with a radial forearm free flap after ablative surgery for tonsil cancers, from Dec. 1997 to Oct. 1998, and analyzed the surgical methods, complications, and speech and swallowing function test results. We have examined with modified barium swallow to evaluate postoperative wallowing function and articulation and resonance test for speech. Results : The tumor sizes by TNM stage(AJCC, 1997) were T1(1), T2(2), and T4(3). The paddles of flaps were tailored in multilobed designs from oval shape to pentalobed design and in variable size from 24$cm^2$ to 108$cm^2$(average size = 78.4$cm^2$), according to the defect after ablation. This procedures resulted in satisfactory flap success and functional results all but 1 case of flap contracture in 2 postoperative week, achieved early oral diet until 16-57 postoperative day(average, 28 days) and social speech. The oropharyngeal defect including soft palate reconstruction with radial forearm free flap might be an excellent method for the maximal functional results, after ablative surgery of tonsil cancer that results in multidimensional defect.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제36권6호
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• pp.298-302
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• 2014

The radial forearm free flap (RFFF) is a thin and pliable tissue with many advantages for tongue reconstruction. However, tongues reconstructed with RFFF occasionally need revision surgery because inadequate defect measurement at primary surgery can lead to bulkiness and limited movement of reconstructed tongue. In this case, the patient underwent partial glossectomy and RFFF reconstruction for treatment of tongue cancer five years prior. We could not make a lower denture for the patient, because the alveolo-lingual sulcus of tongue was almost lost. So we performed vestibuloplasty with a modified Kazanjian method on the lingual vestibule of the mandibular right posterior area, and defatting surgery to debulk the flap. After surgery, we observed that the color and texture of the revised tongue changed to become similar with adjacent tissue. The patient obtained a more functional and esthetic outcome. Accordingly, we present a case report with a review of relevant literature.

• Archives of Reconstructive Microsurgery
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• 제3권1호
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• pp.64-71
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• 1994

해부학적으로 족부는 주위에 이용할 수 있는 연주 조직이 별로 없을 뿐 아니라 이용할 수 있더라도 크기가 제한되어 있으므로 광범위한 연부조직 결손시 이의 복원이 어렵다. 광범위하고 오염된 족부의 창상을 재건시 이상적인 조직의 조건으로서는 감염에 잘 견디고, 가능한한 원래의 모양 및 크기에 가깝게 복원해야 하며, 적절한 감각이 있어야 하고, 끊임없는 마찰력과 체중 부하에 잘 견뎌야 할 것이다. 미세혈관술을 이용한 유리조직이식은 비교적 위와같은 장점들을 제공할 수 있다. 저자들은 최근 약 4년간 외상과 전기화상 및 화상후 후유증으로 인하여 족배부, 발꿈치, Achilles건, 족저부등에 광범위한 결손 및 변형이 있었던 환자 21예에서 미세혈관술을 이용하여 Fasciocutaneous, musulocutaneous, muscle with skin graft 등으로 족부를 재건하여 추적중에 있으며 현재까지 관찰된 결과 및 장점, 단점과 문제점들을 보고하는 바이다.

• 제어로봇시스템학회논문지
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• 제13권7호
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• pp.616-623
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• 2007

A dual micro gas sensor array was fabricated using nano sized $SnO_2$ thin films which had good sensitivities to CO and combustible gases, or $H_2S$ gas for air quality sensors in automobile. The already existed air quality sensor detects oxidizing gases and reducing gases, the air quality sensor(AQS), located near the fresh air inlet detected the harmful gases, the fresh air inlet door/ventilation flap was closed to reduce the amount of pollution entering the vehicle cabin through HVAC(heating, ventilating, and air conditioning) system. In this study, to make $SnO_2$ thin film AQS sensor, thin tin metal layer between 1000 and $2000{\AA}$ thick was oxidized between 600 and $800^{\circ}C$ by thermal oxidation. The gas sensing layers such as $SnO_2$, $SnO_2$(pt) and $SnO_2$(+CuO) were patterned by metal shadow mask for simple fabrication process on the silicon substrate. The micro gas sensors with $SnO_2$(+Pt) and $SnO_2$(CuO) showed good selectivity to CO gas among reducing gases and good sensitivity to $H_2S$ that is main component of bad odor, separately.

• 대한관절경학회지
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• 제14권2호
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• pp.131-134
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• 2010

관절내 골연골 골절은 적절한 치료가 이루어 지지 않은 경우 골관절염을 초래하여 통증과 기능장애를 초래할 수 있다. 골 연골 골절의 크기가 큰 경우에는 관혈적 정복 및 금속고정 수술등으로 치료를 할 수 있으나, 골편의 두께가 2mm 이하로 얇은 경우 튼튼한 고정력을 얻기 어려워 제거 하는 경우가 많았다. 저자들은 대퇴 내과에 발생한 박리성 골연골염 환자와 슬개골 골절로 골편의 두께가 2mm이하인 환자에서 흡수성 반월상 연골나사를 이용하여 좋은 결과를 얻었기에 보고하고자 한다.