• Maxillofacial Plastic and Reconstructive Surgery
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• 제36권4호
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• pp.161-167
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• 2014

Purpose: The reconstruction of mandibular defects poses many difficulties due to the unique, complex shape of the mandible and the temporomandibular joints. With development of microvascular anastomosis, free tissue transplantation techniques, such as deep circumflex iliac artery (DCIA) flap and fibular free flap (FFF), were developed. The DCIA offers good quality and quantity of bone tissue for mandibular segmental defect and implant for dental rehabilitation. Virtual surgical planning (VSP) and stereolithography-guided osteotomy are currently successfully applied in three-dimensional mandibular reconstruction, but most use FFF. There are only a few articles on reconstruction with the DCIA that assess the postoperative results. Methods: Three patients admitted during a five month period (April of 2013 to August of 2013) underwent resection of mandible and DCIA musculo-osseous reconstruction using a VSP and stereolithographic modeling and assessment of outcomes included technical accuracy, esthetic contour, and functional outcomes. Results: This technique yielded iliac bone segment with excellent apposition and duplication of the preoperative plan. Flap survival was 100 percent and all patients maintained preoperative occlusion and contour. Conclusion: Based on our experience, we offer considerations and logically consistent protocols by classification of mandibular defects, and demonstrate the benefits in VSP and stereolithographic modeling of mandibular reconstructive surgery with DCIA flap.

• Archives of Plastic Surgery
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• 제40권3호
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• pp.226-231
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• 2013

Background The reconstruction of volar surface defects is difficult because of the special histologic nature of the tissue involved. The plantar surface is the most homologous in shape and function and could be considered the most ideal of reconstructive options in select cases of volar surface defects. In this paper, we evaluate a single institutional case series of volar tissue defects managed with second toe plantar free flaps. Methods A single-institution retrospective review was performed on 12 cases of reconstruction using a second toe plantar free flap. The mean age was 33 years (range, 9 to 54 years) with a male-to-female ratio of 5-to-1. The predominant mechanism was crush injury (8 cases) followed by amputations (3 cases) and a single case of burn injury. Half of the indications (6 cases) were for soft-tissue defects with the other half for scar contracture. Results All of the flaps survived through the follow-up period. Sensory recovery was related to the time interval between injury and reconstruction-with delayed operations portending worse outcomes. There were no postoperative complications in this series. Conclusions Flexion contracture is the key functional deficit of volar tissue defects. The second toe plantar free flap is the singular flap whose histology most closely matches those of the original volar tissue. In our experience, this flap is the superior reconstructive option within the specific indications dictated by the defect size and location.

• 한국진공학회지
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• 제13권3호
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• pp.120-126
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• 2004

트렌치 소자 제조시 게이트 산화막 성장과 내압 강하의 원인이 되는 식각손상 회복과 코너 영역의 구조를 개선하기 위해 수소 분위기 열처리를 하였다. 열처리시 수소 원자에 의한 환원 반응을 이용하여 표면 에너지가 높은 코너 영역에서는 원자들의 이동에 의한 결정면 재배열, 산화막 측벽에서의 실리콘 원자 적층, 표면 거칠기의 개선 효과 등을 전자현미경 관찰을 통해 확인하였다. 실리콘 원자의 이동을 방해하는 식각 후 잔류 산화막을 수소 가스의 환원성 분위기에서 열처리함으로써 표면 에너지를 낮추는 방향으로 원자의 이동이 일어나 concave 영역, 즉 트렌치 bottom corner에서는 (111), (311) 결정면 재분포 현상이 일어남을 확인할 수 있었다. 또한 convex comer에서의 원자 이동으로 인해 corner 영역에서는 (1111) 면의 step 들이 존재하게 되고 원자 이동에 의해 산화막 측벽에 이르러 이동된 원자의 적층이 일어나며, 이는 열처리시 표면 손상 회복이 원자이동에 의함을 나타낸다. 이러한 적층은 표면 상태가 깨끗할수록 정합성을 띄어 기판과 일치하는 에피 특성을 나타내고 열처리 온도가 높을수록 표면 세정 효과가 커져 식각손상 회복효과가 커지며, 이를 이용하여 이후의 산화막 성장시 균일한 두께를 코너영역에서 얻을 수 있었다

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2005년도 추계학술대회 논문집
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• pp.247-250
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• 2005

The need for improved fuel efficiency, weight reduction has motivated the automotive industry to focus on aluminum alloys as a replacement for steel-based alloy. To cope with the needs for high structural rigidity with low weight, it is forecasted that substantial amount of cast components will be replaced by tubular parts which are mainly manufactured by the extruded aluminum tubes. The extrusion process is utilized to produce tubes and hollow sections. Because there is no weld seam, the circumferential mechanical properties may be uniform and advantageous for hydroforming. However the possibility of the occurrence of a surface defect is very high, especially due to the temperature increase from forming at high pressure when it comes out of the bearing and the roughness of the bearing, which cause the surface defects such as the dies line and pick-up. And when forming a extruded aluminum tube, the free surface of the tube becomes rough with increasing plastic strain. This is well known as orange peel phenomena and has a great effect not only on the surface quality of a product but also on the forming limit. In an attempt to increase the forming limit of the tubular specimen, in the present paper, surface asperities generated during the hydroforming process are polished to eliminate the weak positions of the tube which lead to a localized necking. It is shown that the forming limit of the tube can be considerably improved by simple method of polishing the surface roughness during hydroforming. And also the extent of the crack propagation caused by dies lines generated during the extrusion process is evaluated according to the deformed shape of the tube.

• 복식문화연구
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• 제23권1호
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• pp.32-44
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• 2015

Increasing of Korean old women's rate is demographic characteristics attributed an aging society, silver generation would lead to silver fashion market with steady competitiveness and interest in fashion. So the study attempts to use foundation material for silver's fashion design by analyzing design characteristics and processing development of design representative women's top. Selecting brand for collecting photo using study represents a mid- and premium-priced with reference Brand Yearbook. After selecting brand on domestic and foreign I have collected picture from Internet shopping mall and web-site of fashion brand, from October 2013 to July 2014, but I selected 840 pictures based on front poses for easy decision. In order to search design characteristics according to sort of silver blouse design on domestic and foreign. I have examined shape, color, pattern, fabric sensation, inside composition line and decoration with reference standard of analysis in preceding research. Data analysis method was conducted on analysis of frequency and cross analysis using SPSS statistical package 21.0. The conclusion of design characteristic according to type of blouse design for silver, H-silhouette in shirt blouse seems to fit in body transformation and expose silhouette with correcting the body flaw. Using soft material in T-shirt blouse they are able to conceal a body defect and express beautiful silhouette. By using detail in pullover shirt blouse and tunic blouse for point of design, it express glamour and luxurious. Most of blouse are printed various pattern, it would looks more gorgeous using pattern.

• Journal of Periodontal and Implant Science
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• 제23권3호
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• pp.422-441
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• 1993

The purpose of this study was to compare effects of the bioceramics on healing processes of the alveolar bone defects in dogs. Five adult dogs aged 1 to 2 years were used in this study. Experimental alveolar bone defects were created surgically with a #1/2 round bur at the furcation area of the buccal surface of the mandibular 3rd, 4th premolars and 1st molar. Fifteen experimental alveolar bone defects were devided into three groups according to the type of graft materials. The groups were as follows : 1) flap operation with dense hydroxyapatite( DHA group ) 2) flap operation with porous hydroxyapatite( PHA group ) 3) flap operation with natural coral ( NC group ) At 1, 2, 4, 6, and 12 weeks, dogs were serially sacrificed and specimens were prepared with Hematoxylin-Eosin stain and Mallory stain for light microscopic evaluation. The results of this study were as follows : 1. In every group, inflammatory cell infiltrations were seen at 1st weeks due to surgical trauma, however inflammatory response owing to graft materials were not seen. 2. In every group, the appearance of connective tissue around graft materials was loosely formed at the initial stages, however the connective tissue was densely formed at 2 weeks. 3. The presence of osteocytes were observed at 2 weeks in the natural coral group, however the osteocytes were appeared at 6weeks in the dense hydroxyapatite group. 4. A new bone was formed from the base and walls of the defect and gradually expanded toward the graft materials. 5. A resorption of the natural coral occurred irregularly at the periphery of the material, therefore the size and shape of the natural coral were reduced at 6 weeks. 6. At 12 weeks, the porous hydroxyapatite and natural coral were surrounded by newly formed bone most completely, however dense hydroxyapatite was surrounded by newly formed bone in part.

• 대한두개안면성형외과학회지
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• 제13권1호
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• pp.76-79
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• 2012

Purpose: Sebaceous epithelioma (sebaceoma) is a benign tumor with sebaceous differentiation. It presents primarily as a yellowish papule or nodule on the face and scalp. It must be differentiated from basal cell carcinoma and other appendageal tumors. We report a giant sebaceous epithelioma on the scalp and describe the immunohistochemical character of the cells in sebaceous epithelioma to epithelial membrane antigen (EMA). Methods: A 55-year-old-man who presented with 5-cm-diameter 2-cm-height, round shape exophytic ulcerated tumor on his head presented for treatment. The patient had noticed the lesion 40 years prior as a small yellowish plaque and 18 months ago, the plaque started to grow progressively larger. We excised the lesion with 1 cm resection margin, considering the possibility of malignancy because this lesion grossly resembled basal cell carcinoma (BCC). The defect was repaired with the use of a splitthickness skin graft. Results: When we excised the lesion, the margin was clear. Histology showed nodules that consisted of an admixture of basaloid cells and mature adipocytes lacking an organized lobular architecture. Strong expression of EMA on mature adipose cells confirmed the differential diagnosis from BCC with sebaceous differentiation because of the absence of a nuclear palisade pattern and cleft-like spaces on the hematoxylin and eosin (H&E) section. Conclusion: We treated the giant sebaceous epithelioma on the scalp with surgical excision and a split-thickness skin graft. It is important to know that the diagnosis of sebaceous epithelioma should be made based on the histologic pattern of the H&E section. Immunohistochemistry with EMA can help to confirm the differential diagnosis between sebaceous epithelioma and BCC.

• 조명전기설비학회논문지
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• 제23권2호
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• pp.190-195
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• 2009

본 논문은 모의된 시공불량에 따른 결점을 가진 배전급 종단부의 전기적인 사고에 대하여 실험적으로 조사한 것을 나타낸다. 실험에 조립형과 열수축형인 두 개의 종단재를 사용하였다. 우리는 시공불량에 따른 모의 결점을 가진 케이블 종단부를 제작하여 교류 및 임펄스 내전압 시험과 같은 절연 특성을 고찰하였다. 두께 감소나 하우징의 스트레스콘과 반도전층 사이의 틈과 같은 결점의 영향에 대하여 연구하였다. 절연체의 두께 감소 시 교류 절연파괴 강도는 급격히 감소하였고 이 절연체의 절연파괴 흔적은 타원형으로 나타났다. 스트레스콘과 반도전출 사이의 틈은 절연내력에 매우 나쁜 영향을 주었다. 열수축형에서, 교류 절연파괴 전압은 가열 시간이 짧을 때 낮아졌다.

• 한국기계가공학회지
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• 제16권5호
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• pp.13-18
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• 2017

In this work the augmented safety of Type 4 composite vessel in accordance with uniform-stress design has been demonstrated through a series of burst tests and structural analyses. For this end, three sample vessels were used: (1) designed as guided by the isotensoid dome theory (called iso-dome cylinder); (2) with dome longer compared to uniform-stress design (called prolate cylinder); and (3) with dome wider than uniform-stress design (called oblate cylinder). Structural analyses have been performed using ABAQUS finite element code based on the periodic symmetry to circumferential direction. As a result, the maximum stresses are induced around the bodies of all three cylinders. However, the analyses, with the assumption of possible defect demonstrate that the maximum stresses are induced around the dome knuckles for the prolate and the oblate cylinders. The results of the burst tests for the three cylinders show that the burst initiates from the cylinder body of the iso-dome cylinder and from the dome knuckles of the prolate and the oblate cylinders. Finally, it is recommended that, to comply with DOT CFFC 2007, the dome shape should be designed and fabricated as guided by the isotensoid dome theory.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제29권5호
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• pp.429-438
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• 2007

Transport distraction osteogenesis has been introduced recently to correct skeletal malformations and discrepancies in the maxillofacial area. To reconstruct 3-dimensitonal mandibular shape, this transport distraction can be considered with the use of reconstruction plate. A 23-years-old male having unilateral mandibular body and angle defects, who had been operated of partial mandibular resection due to unicystic ameloblastoma, was treated by transport distraction procedures with ThreadLock transport $distractor^{(R)}$ (KLS Martin Co., Germany) through the rail of reconstruction plate (Osteomed Co., USA). After being distracted 35 mm defect from mandibular angle to body, and consolidated for 16 weeks, allogenic bone graft on docking site was performed with removal of transgingival pin. For more than 13 weeks follow up period after consolidation period, gradual increase of radiopacity in the radiographic examination was shown, and the curved mandibular continuity according to the reconstruction plate was made firmly. These transport distraction osteogenesis in the mandible was able to be considered as the good and minimally invasive technique for the reconstruction of mandibular discontinuity. Young patient was also very satisfactory for these results.