• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제40권4호
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• pp.181-187
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• 2014

Objectives: The purpose of this preliminary study is to evaluate the effectiveness of a customized, three-dimensional, preformed titanium mesh as a barrier membrane for peri-implant alveolar bone regeneration. Materials and Methods: Ten patients were recruited for this study. At the time of implant placement, all patients had fenestration or a dehiscence defect around the implant fixture. A mixture of particulate intraoral autologous bone and freeze-dried bone allograft was applied to the defect in a 1 : 1 volume ratio and covered by the preformed titanium mesh. A core biopsy specimen was taken from the regenerated bone four months postoperatively. Patients were followed for 12 months after the definitive prosthesis was placed. Results: Satisfactory bone regeneration with limited fibrous tissue was detected beneath the preformed titanium mesh. Histologic findings revealed that newly formed bones were well-incorporated into the allografts and connective tissue. New growth was composed of approximately 80% vital bone, 5% fibrous marrow tissue, and 15% remaining allograft. All implants were functional without any significant complications. Conclusion: The use of preformed titanium mesh may support bone regeneration by maintaining space for new bone growth through its macro-pores. This preliminary study presents the efficacy of a preformed titanium mesh as a ready-to-use barrier membrane around peri-implant alveolar bone defect. This preformed mesh is also convenient to apply and to remove.

• 디지털산업정보학회논문지
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• 제9권4호
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• pp.239-249
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• 2013

The role of software process is getting more important to make good quality softwares. One of the measures to improve the software process is Defect Removal Efficiency(DRE). DRE gives a measure of the development team ability to remove defects prior to release. It is calculated as a ratio of defects resolved to total number of defects found. Software Engineering Levels are usually decided by CMMI Model. The model is designed to help organizations improve their software product and service development, acquisition, and maintenance processes. The score of software engineering levels can be calculated by CMMI model. The levels are composed of the three groups(absent, average, and advanced). This study is to find if there is any difference among the three categories in term of the result of software engineering levels on DRE. We propose One way ANOVA to analyze influence of software engineering levels on DRE. Bootstrap method is also used to estimate the sampling distribution of the original sample because the data are not sampled randomly. The method is a statistical method for estimating the sampling distribution of an estimator by sampling with replacement from the original sample. The data were collected in 106 software development projects by the survey. The result of this study tells that there is some difference of DRE among the groups. The higher the software engineering level of a specific company becomes, the better its DRE gets, which means that the companies trying to improve software process can increase their good management performance.

• 융합신호처리학회논문지
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• 제10권2호
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• pp.120-126
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• 2009

반도체 외관결함에는 발생 요인이 각각 다른 crack, foreign material, chip-out, chip, void 등이 있으며, 검사 시스템에서는 결함 유무 및 결함 분류를 수행하여 효과적인 공정관리가 가능하여야 한다. 본 논문에서는 QFN 패키지 결함의 분류를 위한 알고리즘 및 광학시스템을 제안한다. 제안한 방법에서 분류가 어려운 결함 중 하나인 foreign material 과 chip의 효과적인 분류를 위해 제안한 결함의 위치, 밝기의 특징정보(feature)를 사용한 ML(Maximum Likelihood ratio) 분류방법 및 특징정보 획득에 효과적인 광학계를 제안하였다. 실험 결과에서 분류가 어려운 foreign material과 chip에 대한 신뢰성 높은 분류성능을 보였다.

• Journal of Chest Surgery
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• 제21권4호
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• pp.649-655
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• 1988

One hundred and one patients with tetralogy of Fallot who were older than 16 years of age underwent a total correction of the anomaly between May, 1964 and July, 1987. This group comprised 14.9% of the 679 consecutive patients who had repair of the tetralogy at our institution during the same period. Of the 101 patients, 8 had a previous shunt procedure for palliation. The preoperative mean hemoglobin value was 16.9*1.0% and the mean systemic oxygen saturation, 84.4*0.9%. In 76 patients[75.2%], a type II ventricular septal defect was seen whereas in 14 patients[13.9%], the defect was type I. In 72 patients[71.3%], other cardiac anomalies were present which included patent foramen ovale in 37.6%, atrial septal defect in 8.99b, vegetations in 6.9%, right sided aortic arch in 5.9% and coronary artery anomaly in 5.0%. The right ventricular outflow obstruction was caused most commonly by combination of infundibular and valvular stenosis[74.3%], followed by isolated infundibular stenosis[19.8%] and valvular stenosis [5.9%] alone in order. The preoperative mean diameter of the pulmonary valve ring size was 10.2*0.5 mm in diameter. A transannular patch enlargement of the right ventricular outflow tract was performed in 28 patients and, in 12 a pericardial monocusp was utilized. Major anomalous aorto-pulmonary vessels were encountered in 5 patients which were detected before or during the operation. In 3 patients, they were ligated beforehand to control the flooding of the operative field. Postoperatively, the mean systolic pressure gradient between the right ventricle and the main pulmonary artery was 16.2*2.3 mmHg and the mean systolic pressure- ratio between the right and the left ventricle was 45.3*2.0%. Perioperative complications including bleeding in 8.9%, pleural effusion in 7.9%, dysrrhythmia in 4.9%, and residual VSD in 4.0%. Operative mortality was 8.9%. There has been no operative death in the recent 65 cases since 1981. There were 2 late deaths, 68 and 113 months after surgery. There were 2 late detachment of the VSD patch during the follow-up period. Of the 6 patients with patch detachment found during the postoperative period, 3 had subacute bacterial endocarditis before or after the operation indicating The serious nature of this complication. Two of these patients subsequently underwent a successful reoperation.

• 비파괴검사학회지
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• 제30권2호
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• pp.104-109
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• 2010

겹치기 마찰교반용접은 새로운 고상접합법이다. 알루미늄 합금 6061-T6는 좋은 내식성과 중량 대비 높은 기계적 강도로 인해 넓은 분야에서 경량부재로 사용되고 있다. 본 논문에서 사용한 검사 방법인 위상잠금 초음파 적외선열화상기법은 넓은 면적을 동시에 검사할 수 있으며, 결함부와 건전부 사이의 위상차로부터 결함의 유무를 판단할 수 있다. 본고의 연구로부터, 위상잠금 적외선열화상기술을 이용하여 용접부의 열영상을 검출하여 기계적 강도와 비교 평가하였다.

• 대한약침학회지
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• 제25권4호
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• pp.382-389
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• 2022

Objectives: The Korean Industrial Standard (KS) for sterile acupuncture needles was established in 2009 based on research on the quality control of acupuncture needles. We aimed to determine the quality of acupuncture needles available in South Korea in 2021 by examining their surface condition and chemical composition using field-emission scanning electron microscopy (FE-SEM) and energy-dispersive X-ray spectroscopy (EDS). Methods: In South Korea, there are 23 brands of acupuncture needles, and we examined 10-15 needles from each brand, resulting in a total of 285 needles. The microstructures of the needles were assessed by SEM. Using SEM images, we evaluated the acupuncture needle tips for the following defects/aspects: scratches, lumps, detached coating, bent tip, and tip sharpness. EDS was used to determine the chemical composition of the selected acupuncture needles. Results: Overall, 88.4% of 285 needles were found to have at least one type of abnormality. The most frequently observed abnormalities were scratches and dents on the surface (68.1%), followed by detached coating (63.2%), and lumps (61.8%); blunt tips were observed in about 24% of them. Of 252 needles with at least one defect, 86.9% had two or more types of defects. The ratio of the number of needles with any defect to that of needles without any defect varied among brands, ranging from 50% to 100%. Regarding foreign materials, higher proportions of Si and O were observed on the needles, indicating incomplete or detached silicone coating. Conclusion: The quality of acupuncture needles varied among brands, suggesting that further improvements can be made through various inspection methods.

• 한국정보통신학회논문지
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• 제26권11호
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• pp.1720-1728
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• 2022

인공지능 기술의 발전으로 산업 4.0시대가 열렸고 축산업에서도 ICT 기술이 접목된 스마트 농장의 구현이 큰 관심을 받고 있다. 그중에서도 컴퓨터 비전 기반 인공지능 기술을 접목한 축산물 및 축산 가공품의 품질 관리 기술은 스마트 축산의 핵심 기술에 해당한다. 그러나 인공지능 모형 훈련을 위한 축산물 이미지 데이터 수의 부족과 특정 범주(class)에 대한 데이터 불균형은 관련 연구 및 기술 개발에 큰 장해물이 되고 있다. 이러한 문제들을 해결하기 위해, 본 연구에서는 오버샘플링과 적대적 사례 생성기법의 활용을 제안한다. 제안되는 방법은 성공적인 불량 탐지 (Defect detection) 관점을 기반으로 하며, 이는 부족한 데이터 레이블을 효과적으로 활용하는데 필요한 방법이다. 최종적으로 실험을 통해 제안된 방법의 타당성을 확인하고 활용 전략을 검토한다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 춘계학술발표대회
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• pp.414-417
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• 2000

기존의 BACC process의 가장 큰 단점은 탈질이 잘 이루어지지 않는다는 점인데 이것을 보완한 modified BACC process의 경우 실제오수를 사용하여 외부 반송비 따른 질소 및 인의 제거율을 살펴보면 외부 반송비가 200%일 때 $CODC_{Cr}$의 제거율은 평균 $96.3{\sim}95.7%$ 기존의 BACC process와 비슷하나 T-N 제거율은 $88.3{\sim}95.7%$로 월등히 우수한 결과를 보여주고 있다. 충진율 실험에서는 Table 2에서 보는 바와 같이 큰 차이는 없었다.

• Journal of Chest Surgery
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• 제25권4호
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• pp.429-434
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• 1992

We experienced a rare case of traumatic ventricular septal defect by penetrating stab injury The patient was 26-year-old women who got stab wound at the left anterior third intercostal space and left sternal border with a knife. seven hours after admission, the patient was undertaken an emergency thoracotomy due to hypovolemic shock caused by massive bleeding from transected left internal mammary artery, vein, and right ventricular outflow tract. On postoperative second day, the patient was suffered from moderate dyspnea, and arterial blood gas analysis and chest X-ray revealed hypoxemia and pulmonary edema. Right heart cardiac catheterization with Swan-Ganz Cathater showed oxygen step-up between right atrium and main pulmonary artery and a 1.6:1 ratio of pulmonary to systemic blood flow. At operation, harsh systolic thrill was palpable along right ventricular outflow tract. Through small vertical right ventriculotomy, the linear ventricular septal laceration on infundibular septum was noticed, and its size was 1.5cm with sharp margin This defeat was repaired by three interrupted matress sutures using Prolene 4-O with pledget. Her postoperative course was uneventful, and she discharged with good physical condition.

• Journal of Chest Surgery
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• 제20권3호
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• pp.520-527
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• 1987

Clinical analysis was performed of 89 secundum type atrial septal defect patients operated on during the period from July, 15th, 1981 to March, 1987 in the Thoracic and Cardiovascular Surgery Department of Pusan National University Hospital. Secundum type ASD was 2`I.0% among all of congenital heart diseases operated in the same period. The age distribution of patients ranged from 3 to 41 years and sex ratio, male to female was 1.23 to 1.0. Common symptoms were exertional dyspnea 64.0%, frequent upper respiratory infection 43.8%, cyanosis 10.1% and fatigue 7.9%. The mean value of cardiac catheterization data of the group of ASD combined with another cardiovascular anomalies was compared with that of only ASD group. The amount of shunt showed not statistically significant difference between two groups [P>0.05] but pulmonary arterial pressure and pulmonary vascular resistance of combined group was significantly higher than that of only ASD group [P<0.02, P<0.01]. The difference of mean hemodynamic data between the age group below 20 years and above 21 years was not statistically significant [P>0.05]. All cases were operated under cardiopulmonary bypass. Among these 51 were closed directly and 38 were applied Dacron patch. Two most common associated cardiac anomalies were pulmonary stenosis [8 cases, 9.0%] and VSD [8 cases, 9.0%]. The most frequent postoperative complication was wound infection, One patient died of low cardiac output on 10th postoperative day and the overall operative mortality was 1.1%