• 한국산학기술학회논문지
• /
• 제12권2호
• /
• pp.588-593
• /
• 2011

프로그레시브 노칭과 포밍금형에 있어서 박판성형해석에 의한 사전 분석은 제품을 양산하는데 꼭 거쳐야 하는 필수과정이다. 본 논문에서 연구한 Ez5는 일본 S 자동차의 미국 현지 공장에서 발주한 수출 금형을 가지고 스트립 레이아웃 설계에 관한 것을 연구한 것이다. 광폭 1열 1개 뽑기의 편측캐리어를 단 배열로 블랭크 레이아웃을 최적화하여 13개 공정으로 된 스트립 레이아웃설계를 완성하였다. 이런 형태의 금형수주는 앞으로 동시 다발적이고, 매우 빈번히 인터넷 공간상에서 발생할 것이며 금형에 대한 기술력을 갖춘 업체는 이러한 방식에 대응할 준비를 갖추어야 할 것이다.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제32권4호
• /
• pp.351-358
• /
• 2010

A 31-year-old woman with hemifacial microsomia presented to the Department of Oral and Maxillofacial Surgery, Seoul National University Dental Hospital. The patient was previously treated with distraction osteogenesis device to elongate right maxilla and mandibular ramus. But, the result was not satisfactory, to correct residual facial asymmetry due to hemifacial microsomia we planned costochondral graft for reconstruction of ramus and condyle, Le Fort I osteotomy and sagittal split ramus osteotomy for facial asymmetry. The right mandibular condyle and ramus was reconstructed with right eleventh costochondral graft via submandibular approach. Using costochondral graft and orthognathic surgery the facial asymmetry in hemifacial microsomia patient was corrected. 1-stage treatment consists of costochondral graft and orthognathic surgery can achieve function and esthetics at the same time, is timesaving to both patient and surgeon.

• 대한전자공학회논문지
• /
• 제12권6호
• /
• pp.21-30
• /
• 1975

본 논문에서는 복소함수에 대한 최적설계 이론을 제안하여 연산회로, 파형성형회로, 여파기, 증폭기, 전송선로 등의 설계에 적용하여 본 결과, 실험치와도 잘 일치하였으며, 복소함수의 두가지 요소인 절대치와 위상을 동시에 고려한 회로망의 최적설계를 가능하게 하였으며, 또 여러 가지 상이한 회선정수를 포함하는 경우라도 설계가능하도록 무게함수의 선정 방법을 제시하였다. A method by which one can optimize the complex responses of electronic circuits has been suggested. represented in the complex forms, the optimization methods presented so far have dealt with real magnitude and phase responses of circuits. Design examples are shown on the optimal designs of an amplifier, filter, operational circuits transmission lines. and a wave-shaping circuit.

• Archives of Plastic Surgery
• /
• 제33권2호
• /
• pp.135-143
• /
• 2006

The characteristics of the cleft lip nasal deformity is defined in this article in three planes. The alar flaring is explained in X axis, the lower positioning of the alar free margin is imagined in Y axis and the short hemicolumella is in Z axis. Most cleft surgeons have focused on the malposition of the lateral crus of alar cartilage while the author defined it in X and Y axises and tried to correct that deformity of short hemicolumella in Z axis. For the last 13 years the author applied that method in 818 cases of secondary cleft lip nose deformity. Through the columellar splitting incision extended to free margin of the alar not beyond the nasal dorsum, the skin and soft tissue of the webbing deformed the nasal tip was excised in crescent fashion. The dissected short hemicolumella including the medial crus was thus elevated and advanced into the space of the deformed nasal tip after the crescent excision. This procedure should be followed by the correction of the deformities in X and Y axis. The medial crus elevation is more effective and critical way to have the constant and nice outcome than the lateral crus reposition in secondary cleft lip nasal deformity

• Composites Research
• /
• 제12권5호
• /
• pp.87-97
• /
• 1999

층상복합재료란 이종재료들을 적층하여 계면에서 확산에 의하여 새로운 금속조직을 제어하는 것으로 정의한다. 기계적 성질이 다른 금속이 결합하여 서로의 단점을 보완·개선함으로써 재료의 기계적 성질을 한층 더 향상시킬 뿐만 아니라, 동시에 전기적 성질도 향상시킬 수 있는 재료로 그 종류는 다양하며 용도도 광범위하다. 본 연구에서는 Al/Cu 피복이종복합재료를 직·간적압출하는데 필요한 성형 조건을 도출하기 위하여 유한요소 상용 package인 DEFORM을 이용하여 이종복합재료의 거동해석을 수행하였다. 압출해석에 필요한 물성치를 구하기 위하여 본 연구에서 제조한 재료를 이용하여 압축실험을 수행하였으며, 압출방법, 압출온도, 피복재의 두께 등의 변화에 다른 이종복합재료의 거동을 파악하였다. 또한 해석결과를 바탕으로 이종복합재료의 열간압출실험의 결과와 비교·검토하였다.

• Archives of Plastic Surgery
• /
• 제37권1호
• /
• pp.22-25
• /
• 2010

Purpose: As patients who take immediate breast reconstructions with TRAM flap have increased, concomitant or delayed other elective intra-abdominal operations in these patients also have increased. There are few reports of concomitant or delayed intra-abdominal operation in TRAM flap patients. We report our experiences and outcomes of these operations which is safe and feasible. Methods: We reviewed the charts and postoperative follow-up results of 11 patients among 471 consecutive patients who took immediate breast reconstruction with TRAM flap from December of 2002 to September of 2006. Four patients took concomitant intra-abdominal operation and 7 patients took delayed intra-abdominal operation between 1 to 52 months after TRAM flap Results: There were no significant postoperative abdominal and systemic complications. One patient who took concomitant intra-abdominal operation presented partial skin necrosis of abdomen, but recovered completely with conservative treatments. Two patients took transfusion in peri-operative periods. Conclusion: Concomitant or delayed intra-abdominal operation in immediate breast reconstruction with TRAM flap could be performed safely and feasibly when it is necessary. Furthermore, it could be helpful to patients and surgeons.

• 한국정밀공학회지
• /
• 제17권7호
• /
• pp.124-131
• /
• 2000

Rapid Prototyping(RP) models are no longer used only for design verification. Currently, parts built utilizing layer manufacturing technology can be employed as functional prototypes and as patterns or tools for different manufacturing processes such as vacuum casting, investment casting, injection molding, precise casting and sand casting. This trend of Rapid Prototyping application meets the requirement of concurrent engineering and its range covers a more spreaded area. The aim of this paper is saving the manufacturing lead time and cost of plastic parts having hollow space shapes used by prototype-car. Using rapid prototype patterns, made by the Selective Laser Sintering(SLS) technique, a new approach of manufacturing resin-based blow mold is discussed. It has a great potential fur making prototype-car parts with the batch size of under 200 parts, in case of rapid modification due to a subsequent design changes in developing stage. So, the process proposed in this research shows reduction of process time and manufacturing cost when compared with the conventional process such as a Zinc Alloy fur Stamping(ZAS) mold.

• Archives of Plastic Surgery
• /
• 제32권1호
• /
• pp.37-42
• /
• 2005

The human nose is located in the center of the face and it's cosmetic importance is high. The contour of the nasal dorsum and side walls play a major role in the shaping of the nose, and even a slight distortion may results in significant variance of the human facies. However, in the case of patients with wide nasal bone, augmention rhinoplasty can make nasal planes look wide, resulting in bulbous appearing noses or lateral borders of the nasal implant may be visible after the surgery making the final cosmetic results unsatisfactory. To solve such problems, from march, 1999 to march, 2004, the authors have performed augmention rhinoplasty in 36 patients. The cause of operations were as follows: flat nose 20, hump nose 5, deviated nose 4, secondary rhinoplasty 7. Paramedian osteotomy was performed at a distance that was the same as the width of the implant from the midline(5 mm + 5 mm). To prevent it from connecting to the roof at the lateral osteotomy line, intentional green stick fracture of the roof was performed. Agumentation rhinoplasty was done with either Silicone or Gortex and ear cartilage as a supplement. The follow up period was 2 weeks to 13 months with an average of 5.5 months. There were no infections and postoperative bleeding. As a result, the nose was augmented higher and narrower than before which we and the patient both found highly satisfactory.

• Archives of Plastic Surgery
• /
• 제32권6호
• /
• pp.787-790
• /
• 2005

While no scar can be completely erased, most linear facial scars can result in a relatively good scar after revision. However, in case of round shaped depressed scar, the scar is often lengthened following an incisional technique. This study focuses on the technique of dermofat graft harvested from the adjacent scars for correction of depressed scars. 18 patients having multiple facial scars with a depressed scar among 375 patients who had undergone scar revision were treated from June 2003 to May 2004. Dermofat was harvested from the adjacent linear scar, then it was deepithelialized, reshaped, and grafted to the depressed scar through a small incision. Cosmetic results were generally good. Complications were overcorrection in 4 patients; hyperpigmentation occured in 1 patient. However, 13 patients were satisfied with the results. The advantages of our technique are as follows: it does not require additional operation; dermofat graft has low absorbable rate; it can maintain the volume with an adequate texture.

• Archives of Plastic Surgery
• /
• 제35권1호
• /
• pp.96-99
• /
• 2008

Purpose: A meningoencephalocele is a congenital malformation involving herniation of the meninges and cerebral tissue through a defect in the skull. For the patient with frontoethmoidal meningoencephalocele with hypertelorism, the removal of the meningoencephalocele without correction of the combined hypertelorism is not enough for getting a good cosmetic appearance. Correction of the hypertelorism is needed for cosmetic problem. We experienced a case of simultaneous correction of frontoethmoidal meningoencephalocele with hypertelorism. Methods: The meningoencephalocele was removed and the hypertelorism was corrected by central segment technique. The bone defects were filled with autogenous bone dusts. And the nose was reconstructed by a calvarial bone graft. Results: The patient had a good cosmetic appearance without any neurological complications without serious complications. Conclusion: We experienced a case of simultaneous correction of frontoethmoidal meningoencephalocele with hypertelorism. And a brief review of related literatures is given.