• 한국생산제조학회지
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• 제22권4호
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• pp.686-692
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• 2013

Today, environmental issues have become a matter of worldwide concern. In particular, automobile industries engage in considerable research and investment to develop high-efficiency and ecofriendly cars. Most ecofriendly cars use natural gas or hydrogen gas instead of fossil fuels. In this regard, low-weight and high-pressure vessels have gradually been developed to increase the driving distance of a car. However, most pressure vessels installed in cars develop many defects over time owing to shocks sustained when the car is being driven. Such defects can cause the explosion of the pressure vessel. Therefore it is important to prevent such explosions due to internal defects. The use of shearography for measuring the internal defects of objects afford many advantages. It is a non-contact and non-destructive method, and it is not limited by the object shape. In this study, the internal defect deformation and strain of an aluminum liner that is used in a CNG bus for the fuel storage tank is measured using shearography. It is important to measure the strain and deformation in order to detect defects and repair the pressure vessel. To verify the accuracy of the shearography measurement method, the measurement results of shearography, out-of-plane ESPI, and FEM are compared quantitatively.

• Journal of Chest Surgery
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• 제42권4호
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• pp.516-519
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• 2009

심근 경색 후 발생하는 심실 중격 결손은 드문 질환이다. 그러나 심실 중격 결손이 발생한 경우 서둘러 수술을 하지 않으면 90% 이상의 환자가 사망에 이르는 매우 위험한 질환이다. 심근 경색 후 심실 중격 결손에 대한 수술 방법은 여러 가지가 알려져 있는데 이는 약해진 경색 조직의 봉합부위가 다시 파열되어 중격 결손이 재발하는 것을 방지 하지 위하여 다양한 방법들이 소개되어 왔기 때문이다. 저자들은 관상동맥 조영술상 이상 소견을 보이지 않는 Prinzmetal형 협심증에 의한 심실 중격 결손과 가성 좌심실류의 파열 소견을 보인 환자를 "Sandwich technique"을 이용해 성공적으로 치료하였기에 보고하고자 한다.

• International Journal of Naval Architecture and Ocean Engineering
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• 제10권2호
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• pp.153-169
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• 2018

A submarine has a pressure hull that can withstand high hydraulic pressure and therefore, requires the use of highly advanced shipbuilding technology. When producing a pressure hull, periodic inspection, repair, and maintenance are conducted to maintain its soundness. Of the maintenance methods, Non-Destructive Testing (NDT) is the most effective, because it does not damage the target but sustains its original form and function while inspecting internal and external defects. The NDT process to detect defects in the welded parts of the submarine is applied through Magnetic particle Testing (MT) to detect surface defects and Ultrasonic Testing (UT) and Radiography Testing (RT) to detect internal defects. In comparison with RT, UT encounters difficulties in distinguishing the types of defects, can yield different results depending on the skills of the inspector, and stores no inspection record. At the same time, the use of RT gives rise to issues related to worker safety due to radiation exposure. RT is also difficult to apply from the perspectives of the manufacturing of the submarine and economic feasibility. Therefore, in this study, the Phased Array Ultrasonic Testing (PAUT) method was applied to propose an inspection method that can address the above disadvantages by designing a probe to enhance the precision of detection of hull defects and the reliability of calculations of defect size.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제18권3호
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• pp.371-377
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• 1996

Bone graft has been used to repair one defect caused by disease and trauma, congenital and acquired deformities. Graft materials are autogenous bone, allogenic bone, xenogenic bone, synthetics. Autogenous bone graft is the most superior to other materials for immunologic reaction, compatibility to host tissue, and revascularization. However, autogenous bone graft is required for additional operation and the amount of taking is limited. Autografts are obtained at own expense and also limited in size, shape. In order to compensate these problems, allogenic bone graft has been used increasingly. But allogenic bone graft encounters immunologic complications. Therefore, it has been used after freezing, lyophilization, or demineralization. Allogenic bone processed by only lyophilization includes potential antigenic properties on its surface, therefore it is demineralized to deplete immunologic reaction. Demineralized bone releases BMP and helps the mesenchymal cells transform to the chondroblast to produce cartilage and bone. This reaction is called osteoinducation. Many authors have reported that mineralized lyophilized bone had less antigenicity clinically and favorable bony consideration with host bone. In our department from 1995 to now, we have used banked allogenic bone graft that has been prepared from Wonkwang Bone Bank in 5 cases and mineralized lyophilized bone graft in 2 cases to reconstruct the maxillofacial bone defect after tumor resection and cyst enucleation and cleft alveolus. We will report with literature review that the result is favorable functionally and esthetically.

• Journal of Chest Surgery
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• 제24권1호
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• pp.15-25
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• 1991

From February 1988 to December 1990, 42 patients underwent so called REV operation for pulmonary stenosis or atresia with or without anomalies of ventriculoarterial connection and truncus arteriosus. The principles of operative technique are mobilization of pulmonary arterial tree beyond the pericardial reflection, transection of pulmonary trunk between the pulmonary ventricle and pulmonary artery, suture of distal pulmonary arterial stump to the upper margin of Pulmonary ventriculotomy site with absorbable suture, and anterior patch with 0.625% glutaraldehyde fixed autologous pericardium with monocusp inside it. Age at operation ranged 3-156months [mean 41.8 month] with twelve of whom infants. Operative indications were pulmonary atresia, with ventricular septal defect[16], and pulmonary stenosis with double outlet right ventricle[8], with ventricular septal defect[16], with double outlet right ventricle[8], with complete transposition of the great arteries[8], with corrected transposition of the great arteries[6], with Fallot`s tetralogy[3], and truncus arteriosus[1]. There were six hospital deaths[14%] and no late death. Twenty-four of 36 survivals were followed up more than 12 months with good clinical results. Postoperative angiocardiogram was performed in fifteen patients. Hemodynamically, two patents had residual pressure gradients along the pulmonary outflow tract, one patient showed severe pulmonary regurgitation; morphologically, there were six significant stenosis of left pulmonary arterial tree, two of whom showed significant pressure gradients. Our present experience with REV operation suggests that this technique make it possible to perform anatomic repair in a wide variety of congenital anomalies of abnormal ventriculoarterial connection associated with pulmonary outflow tract obstruction without using the prosthetic material, even in infants, with relatively low mortality and morbidity.

• Journal of Chest Surgery
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• 제23권3호
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• pp.474-481
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• 1990

We have experienced 44 cases of coarctation of aorta in the age of infancy and children from April 1986 to September 1989 at Seoul National University Children`s hospital. Patients were thirty males and fourteen females, and their age ranged from one month to ten years[mean 23.84 $\pm$33.06 months] with thirty-two infant cases. In the infantile age, congestive heart failure was the most common chief complaint[18/32], and above that age, frequent upper respiratory infection was most common[8/12]. We experienced thirteen cases of isolated COA, twenty-two cases of COA with VSD, eight cases of COA with VSD, eight cases of COA with intracardiac complex anomalies and one case of COA with atrial septal defect. The associated intracardiac complex anomalies were three Taussig-Bing type double outlet right ventricle, one single ventricle, one transposition of great arteries, one atrioventricular septal defect, one hypoplastic aortic arch with left heart hypoplasia, and one Tetralogy of Fallot. Operative techniques of COA were twenty-three subclavian flap arterioplasty, 12 resection and end to end anastomosis, eight onlay patch angioplasty, and I direct angioplasty after resection of web. Among the cases with other cardiac anomalies, staged operation was done in twenty-nine patients, and single stage total correction was performed only in three patients. There were seven operative mortality[15.9%], all being in infantile age group, and among fourteen cases associated with large VSD[Qp/Qs>2.0, mean pulmonary arterial pressure>50mmHg], four patients were died, but there was no mortality in patients with small VSD. With above results, we are intended to discuss about the interval between staged operation, the fate of VSD after coarctoplasty in case of COA with VSD, causes of death, complications etc.

• Journal of Periodontal and Implant Science
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• 제29권1호
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• pp.153-171
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• 1999

The purpose of this study was to evaluate the effect of modified calcium sulfate paste on periodontal regeneration. l-wall intrabony defect(mesio-distal width: 4mm, depth: 4mm) was surgically created on the distal side of P2 and mesial side of p4 in four dogs. The control group(GFS) was treated with conventional flap operation alone, and the experimental group(CS) was treated with conventional flap operation with modified calcium sulfate paste application. Both control and experimental groups were sacrificed after 8weeks of healing period, The results of histological and histometric observations were as follows. 1. The length of the junctional epithelium was 0.41${\pm}$0.01mm in the control groups, 0.47${\pm}$0.01mm in the experimental group. 2. The connective tissue attachment was 0.28${\pm}$0.02mm(6.15${\pm}$0.28%) in the control group, 0.18${\pm}$0.01mm(3.41${\pm}$0.14%) in the experimental group. The control group showed more connective tissue attachment. 3. The new cementum formation was 3.80${\pm}$0.06mm(84.80${\pm}$0.33%) in the control group, 4.49${\pm}$0.06mm(87.57${\pm}$0.15%) in the experimental group. Both groups showed a lot of new cementum formation. 4. The new bone formation was 1.43${\pm}$0.03mm(32.37%) in the control group, 2.04${\pm}$O.09mm(40.94%) in the experimental group. 5. The inflamatory cells were observed partially around resorbed calcium sulfate in the connective tissue of the experimental group. 6. Partially resorbed calcium sulfate were found within the connective tissue, around alveolar bone, and in the newly formed alveolar bone, On the basis of these results, newly formed calcium sulfate paste enhanced new bone formation and new cementum formation. The resorption rate of calcium sulfate seems to be controlled by the add-in compounds. Thus research about biocompatibility and adequate resorptionrate is required to develop a improved material.

• Journal of Yeungnam Medical Science
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• 제9권2호
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• pp.321-326
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• 1992

영남대학교 의과대학 흉부외과학 교실에서는 1985년 6월 부터 1992년 8월까지 35세이상의 성인 심방중격환자를 수술로 치험한 15례에서 다음과 같은 결과를 얻었다. 1. 수술은 11례(73%)에서 인조포편 및 자가심막을 사용하여 봉합하였다. 2. 단락정도와 수축기 폐동맥압과의 관계에서 특이한 상관관계가 없었다. 3. 술전의 뉴욕심장협회 기능분류 II가 6명, III이 8명 이었는데 술후 I이 8명, II가 6명으로 증상의 호전 있었다. 4. 심방세동 4례중 술후 3례에서 지속적으로 나타났고 1례에서는 정상리듬으로 돌아왔다. 5. 수술사망율은 없었고 수술결과는 만족하였다.

• Journal of Chest Surgery
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• 제17권3호
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• pp.371-380
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• 1984

Corrected transposition of the great arteries [C-TGA] is one of the rare congenital heart disease in which there is both a discordant atrioventricular relationship and transposition of the great vessels. With this arrangement, systemic venous blood passes through the right atrium into the morphologic left ventricle and out the pulmonary artery. Pulmonary venous blood returns to the left atrium, flows into the morphologic right ventricle and out the aorta. Thus, in the rare case when no additional cardiac anomaly is present, a hemodynamically normal heart exists. But more often they are symptomatic as a result of one or several of the commonly associated defects. This paper describes 13 patients who underwent repair of one or more cardiac anomalies associated with corrected transposition at SN UH, from June 1976 through June 1984. 1.8 were males and 5 females, with ages ranging from 3 years to 27 years. 2. Segmental anatomy was {S,L,L} in 12, or {I,D,D} in 1. 3.Associated anomalies were ventricular septal defect in 10, pulmonary outflow tract obstruction in 6, tricuspid insufficiency in. 4, atrial septal defect in 3, subaortic stenosis in 1, mitral insufficiency in 1, and patent ductus arteriosus in 1. 4.None had complete heart block preoperatively, and 3 developed complete heart block intraoperatively. But one of them recovered sinus rhythm on the postoperative 7th day spontaneously. 5.There were 3 cases of hospital morality. But there was no morality since Dec. 1980. 6.Patients with single ventricle, hypoplastic ventricle or those who had palliative surgery alone are not included in this review.

• 대한관절경학회지
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• 제13권1호
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• pp.14-21
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• 2009

목적: 관절경하 일차 봉합술 후 전방 십자인대의 자기 공명 영상 소견에 대하여 알아보고자 하였다. 대상 및 방법: 봉합사 견인 결찰(pull-out) 기법으로 관절경하 일차 봉합술을 시행한 17예를 대상으로 하였다. 평균 추시 기간은 21.4개월(범위: 12~60개월)이었다. 외래 방문시 신체 검사 및 KT-1000 arthrometer (MEDmetric, San Diego, CA) 측기로 안정성을 검사하였으며 수술 후 자기 공명 영상으로 추적하였다. 남아 있는 활막 소매(synovial sleeve)의 위치로 정의한 파열부의 위치에 따라 환자를 두 군으로 분류하였으며 제 1군은 파열이 대퇴골 부착 부위부터 근위 1/3 실질부 이내에 위치하는 경우, 제 2군은 파열이 근위 1/3 실질부 보다 원위에 위치하는 경우로 하였다. 수술 후 자기 공명 영상소견을 일정한 주기로 촬영하였으며 봉합된 십자인대의 주행 경로, 경계의 명확성, 두께 및 신호 강도를 3등급으로 분류하여 평가하였으며 두 군간의 차이를 분석하였다. 결과: 모든 예에서 Lachman검사와 flexion-rotation drawer 검사는 음성이었으며 Pivot-shift 검사는 1도 이하였으며 건측과 환측의 KT-1000 arthrometer 차이는 평균 1.4 mm(범위: -1.0~2.5 mm)로 측정되었다. 파열부 위치에 따른 분류로 제1군은 11예, 제 2군은 6예가 해당하였다. 자기 공명 영상 소견상 모든 예에서 전방 십자 인대의 전반적인 연속성은 유지되고 있었으나 10예(58.8%)에서 경도의 처진 주행 경로를 보였고 6예(35.3%)에서 경도의 불명확한 경계를 보였으며 8예(47.1%)에서 두께의 증가, 5예(29.4%)에서 신호 강도의 증가를 보였다. 모든 항목에서 두 군간 유의한 차이는 없었다. 한편, 시상면상 제1군의 2예(18.2%), 제 2군의 5예(83.3%), 전체 환자의 7예(41.2%)에서 대퇴골 부착 부위의 후방 변연부 실질부의 국소 결핍 소견이 관찰되었으며 이는 제2군에서 의미 있게 더 높은 빈도로 관찰되었다(p=0.035). 결론: 일차 봉합술 후 임상적으로 불안정이 없는 슬관절의 자기 공명 영상 검사 소견으로 주행 경로의 처짐, 경계의 불명확, 두께 및 신호 강도의 증가, 대퇴 부착 지점의 국소 결핍 등의 비정상 소견을 보일 수 있다. 한편 대퇴 부착부의 국소결핍 소견은 파열의 위치와 관계가 있다.