• Archives of Plastic Surgery
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• 제37권5호
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• pp.607-612
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• 2010

Purpose: Maxillectomy for malignant tumor resection often leads to functional and aesthetic sequalae. Reconstruction following maxillectomy has been a challenging problem in the field of head and neck cancer surgery. In this article, we described three dimensional midface reconstructions using free flaps and their functional and aesthetic outcomes. Methods: We reconstructed 35 cases of maxillectomy defects using 9 radial forearm free flaps, 7 lattisimus dorsi musculocutaneous free flaps, 6 rectus abdominis musculocutaneous free flaps, 4 fibular osteocutaneous free flaps, and 9 anterolateral thigh free flaps, respectively. We classified post-maxillectomy defects by Brown's classification. 1 Articulation clarity was measured with picture consonant articulation test. Swallowing function was evaluated with the University of Washington quality-of-life Head and Neck questionnaire by 4 steps.2 Aesthetic outcomes were checked to compare preoperative with postoperative full face photographs by 5 medical doctors who did not involve in our operation. Results: The average articulation clarity was 92.4% (100-41.9%). 27 (81.9%) patients were able to eat an unrestricted diet. Aesthetic results were considered excellent in 18 patients (51.4%). Functional results were best in the group reconstructed with fibular osteocutaneous free flap. Considering the range of wide excision, aesthetic results is best in the group reconstructed with anterolateral thigh free flap. Conclusion: The free flap is a useful technique for the reconstruction of the midface leading to good results, both functionally and aesthetically. Especially, because osteocutaneous flap such as fibular osteocutaneous free flap offered bone source for osteointegrated implant, It produces the best functional results. And perforator flap like as anterolateral thigh free flap reliably provides the best aesthetic results, because it provides sufficient volume and has no postoperative volume diminution.

• 한국식생활문화학회지
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• 제7권4호
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• pp.303-307
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• 1992

The lipid compositions of buckwheats produced in Korea were analyzed. The samples used in this experiment were as follows; Kyungbuk rice buckwheat. Kangwon hull buckwheat and Kangwon rice buckwheat. The total lipids were extracted and fractionated to neutral lipids, glycolipids and phospholipids respectively by silicic acid column chromatography (SACC). As a result, neutral lipids content of these three samples were in the range of 82.77-95.65%; glycolipids in 1.97-10.83%; and phospholipids in 2.21-6.40%. The composition of neutral lipids of these three samples showed that triglyceride were in the range of 88.7-92.0%; monoglyceride in 2.3-4.0%; free fatty acid in 3.0-3.7%; diglyceride in 0.7-0.8%.; free sterol in 0-0.7%; and steryl esters in 0-2.2%. The major fatty acids of total lipid, neutral lipid, glycolipids and phospholipids of these three samples were oleic, linoleic and palmitic acids.

• 한국광학회지
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• 제9권3호
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• pp.151-155
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• 1998

회절손실을 줄이기 위해 별도로 빔의 크기를 제한하기 위한 부품이나 정렬용 부품을 사용하지 않고도 공극이 10um이 상인 새로운 구조의 Fabry-Perot형 파장가변 필터를 제작하였다. 이를 위해서 FP 공진기를 이루는 두 광섬유중 수신용 광섬유의 단면을 1차측 광섬유에서 나오는 Gaussian 빔 파면의 곡률과 같은 곡률의 곡면으로 가공하였다. Cleaved된 광섬유 단면 곡면가공된 광섬유 단면에 고반사율 유전체 코티을 수행한 후 단일모드 광섬유-곡면가공 단일모드 광섬유로 배치한 Fprhdwlsrl형 필터를 제작하였으며, 제작된 필터의 통과파장폭, free spectral range, 삽입손실은 각각 1.47nm, 52nm, 그리고 5.6dB이었다.

• Journal of Communications and Networks
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• 제7권4호
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• pp.429-437
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• 2005

Sensor localization has become an essential requirement for realistic applications over wireless sensor networks (WSN). In this paper we propose an ad hoc localization algorithm that is infrastructure-free, anchor-free, and computationally efficient with reduced communication. A novel combination of distance and direction estimation technique is introduced to detect and estimate ranges between neighbors. Using this information we construct unidirectional coordinate systems to avoid the reflection ambiguity. We then compute node positions using a transformation matrix [T], which reduces the computational complexity of the localization algorithm while computing positions relative to the fixed coordinate system. Simulation results have shown that at a node degree of 9 we get $90\%$ localization with $20\%$ average localization error without using any error refining schemes.

• 한국광학회:학술대회논문집
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• 한국광학회 2000년도 제11회 정기총회 및 00년 동계학술발표회 논문집
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• pp.72-73
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• 2000

Optical fiber gratings have been intensively studied for applications in optical fiber communications and sensor systems due to their all-fiber configuration, low insertion loss, low cost, and high flexibility. Especially, cladding mode coupling fiber devices such as long period gratings (LPG) and acousto-optic tunable filters (AOTF) have been developed as a gain equalization filter in erbium doped fiber amplifier (EDFA) for wavelength division multiplexing (WDM) systems$^{(1-2)}$ . (omitted)

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2005년도 춘계학술발표대회 논문집
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• pp.253-256
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• 2005

Nonlinear aeroelastic analyses of composite wing with flap are performed considering free-play and dynamic stiffness of actuator. Doublet-Hybrid method is used for the calculation of subsonic unsteady aerodynamic forces. Free-play is modeled as an asymmetric bilinear spring and is linearized by using the describing function method. The linear and nonlinear flutter analyses show that the flutter characteristics are significantly dependent on the free-play and dynamic stiffness. From the nonlinear flutter analysis, various types of limit cycle oscillations are observed in a range of air speeds below or above the linear divergent flutter boundary.

• 대한기계학회논문집
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• 제18권8호
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• pp.1899-1909
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• 1994

This work presents the experimental and FEM results for the free vibration of cantilevered, symmetrically and antisymmetrically laminated composite rectangular plates. The natural frequencies, mode shapes and contour plots of a number of CFRP, GFRP, DFRP-Aluminum, GFRP-Aluminum and DFRP-GFRP hybrid composite plates are experimentally obtained. Determination of Young's modulus and test procedures are described. The natural frequencies are determined for a wide range of parameters : e.g. , composite material constants, fiber angles and stacking sequences. Natural frequency and nondimensional frequency parameter results are compared with the finite element analysis and existing literatures. Agreement between experimental and calculated frequencies is excellent. The effects of varing the parameters upon the free vibration frequencies and mode shapes are discussed.

• Journal of Welding and Joining
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• 제23권1호
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• pp.77-85
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• 2005

The structures and mechanical properties of friction stirred welds of oxygen free copper(OFC) sheet were investigated. Defect-free welds were obtained in a relatively wide range of the welding conditions from 1000 to 2000 rpm, and welding speed from 500 to 2000 mm/min. The microstructure of the stirred zone(SZ) showed recrystallized grains, and the gram size varied largely with the welding conditions. The SZ hardness values including those of all the optimum welding conditions were slightly lower than that of the base metal, and increased with decreasing heat input. The tensile strength of the all-SZ increased with increasing the hardness values. The Hall-Fetch relationship was confirmed between the yield strength of the all-52 and the recrystallized grain size of the SZ.

• 한국응용과학기술학회지
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• 제28권4호
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• pp.517-525
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• 2011

Squid ink was added to the low salt fermented squid by 4% of concentration and ripened at $10^{\circ}C$ for 6 weeks and at $20^{\circ}C$ for 28 days. The effect of the squid ink on the titrable acidity and free amino acids of low salt fermented squid were investigated. The results are as follows; The titrable acidity in the salt fermented squid without addition of the squid ink was continuously decreased except for the salt fermented squid with 9% salt content till the latter stage of the ripening, had larger decreasing range than treatment groups. Seeing the composition of free amino acid, the major amino acids are proline, arginine, glutamic acid. leucine and glycine.

• Structural Engineering and Mechanics
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• 제59권6호
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• pp.1055-1070
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• 2016

The aim of this experimental study is to investigate the free vibration and buckling behaviors of hybrid composite beams having different span lengths and orientation angles subjected to different impact energy levels. The impact energies are applied in range from 10 J to 30 J. Free vibration and buckling behaviors of intact and impacted hybrid composite beams are compared with each other for different span lengths, orientation angles and impact levels. In free vibration analysis, the first three modes of hybrid beams are considered and natural frequencies are normalized. It is seen that first and second modes are mostly affected with increasing impact energy level. Also, the fundamental natural frequency is mostly affected with the usage of mold that have 40 mm span length (SP40). Moreover, as the impact energy increases, the normalized critical buckling loads decrease gradually for $0^{\circ}$ and $30^{\circ}$ oriented hybrid beams but they fluctuate for the other beams.