• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2005년도 제25회 추계학술대회논문집
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• pp.158-161
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• 2005

본 연구에서는 Support Vector Machine (SVM)을 이용하여 가스 터빈 엔진의 결함 진단을 시도하였다. SVM은 벡터 공간에서 임의의 비선형 경계인 Hyperplane을 찾아 두 개의 집합을 분류하는 방법으로 수학적으로 최적의 해를 찾을 수 있다고 알려져 있다. 이러한 이진 분류용 SVM을 다층으로 결합하여 가스 터빈의 결함을 정량적으로 판단해 내는 방법을 제안하였으며 기존의 Multi Layer Perceptron(MLP)보다 빠르고 신뢰성 있는 진단 결과를 보여주었음을 확인하였다.

• Journal of Chest Surgery
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• 제17권2호
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• pp.250-256
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• 1984

Eisenmenger syndrome is a condition which systemic arterial blood oxygen unsaturation occurs if obstruction in the pulmonary capillaries raises the pulmonary vascular resistance and pulmonary arterial pressure to or beyond systemic levels and then a significant right to left shunt develops across a preexisting cardiac septal defect or an aortopulmonary communication-We have experienced 3 cases of similar condition. Case I is 24 year old man who has had cyanosis and dyspnea on exertion since childhood. His pulmonary arterial pressure was 110/80mmHg. He was operated under diagnosis of the mitral stenosis and tetralogy of Fallot, but it was finally discovered that he had patent ductus arteriosus and ventricular defect was closed with perforated prosthetic patch, but the patient expired due to right heart failure low cardiac output. Case II was 16 year old female who had pulmonary hypertension of 110/85mmHg. She was diagnosed as Eisenmenger syndrome combining with atrial septal defect and patent ductus arteriosus. Case III was 20 year old male. His pulmonary arterial pressure was 110/70mmHg and the underlying defect was patent ductus arteriosus.

• Journal of Chest Surgery
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• 제11권2호
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• pp.175-180
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• 1978

A rare form of tetralogy of Fallot, in which large ventricular septal defect was located at subpulmonary position rather than beneath a well developed crista supraventricularis was operated in this Department. This case satisfied the criteria for the diagnosis of tetralogy of Fallot, having large ventricular septal defect beneath the aortic valve with overriding of aorta, pulmonary stenosis and right ventricular hypeFtrophy. The operation was done through a median sternotomy using cardiopulmonary bypass. A vertical right ventriculotomy was extended to the pulmonary valve ring. Pulmonary and aortic valve were adjacent to each other, in contrast to the situation of classic tetralogy of Fallot. Pulmonary valvulotomy was done and ventricular septal defect was closed. with Teflon, and right ventricular outflow tract was reconstructed with woven Dacron covered by pericardial patch after minimal resection of septal band. The post-operatiove courses was uneventful except wound infection. The patient was discharged 15 days after open heart surgery.

• Smart Structures and Systems
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• 제11권3호
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• pp.299-314
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• 2013

This paper presents a nonlinear time series analysis technique for evaluating machine defect severity, based on the Recurrence Plot (RP) entropy. The RP entropy is calculated from the probability distribution of the diagonal line length in the recurrence plot, which graphically depicts a system's dynamics and provides a global picture of the autocorrelation in a time series over all available time-scales. Results of experimental studies conducted on a spindle-bearing test bed have demonstrated that, as the working condition of the bearing deteriorates due to the initiation and/or progression of structural damages, the frequency information contained in the vibration signal becomes increasingly complex, leading to the increase of the RP entropy. As a result, RP entropy can serve as an effective indicator for defect severity assessment of rolling bearings.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 D
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• pp.2846-2848
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• 2005

This paper proposes a pattern classification algorithm for the defect distribution of Hard Disk Drive (HDD). In the HDD productions, the defect pattern of defective HDD set is important information to diagnosis of defective HDD set. In this paper, 5 characteristics are determined for the classification to six standard defect pattern classes. A fuzzy inference system is proposed, the inputs of which are 5 characteristic values and the outputs are the possibilities that the input pattern is classified to the standard patterns. Classification result is the pattern with maximum possibility. The proposed algorithm is implemented with a PC system for defective HDD sets and shows its effectiveness.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제55권3호
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• pp.127-133
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• 2006

This Paper describes a dual bands PD measurement method which has two different bandwidths. The one bandwidth is 0.5 - 2 GHz and the other is 1 - 2GHz. This method is used for GIS diagnosis. In the experiment, it shows that the ratios between two PD quantities in dual bands depend on the defect types and gas pressures. The variations of ratios in different pressures are more sensitive than ones in defect types. And These ratios increase with increasing SF6 gas pressures. As these ratios give us additive information of PD we can analyze the defect type as well as risk assessment for the GIS reliably. Therefore the above result shows that these ratios are one of parameters for diagnosing GIS.

• Journal of Chest Surgery
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• 제25권8호
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• pp.832-836
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• 1992

A 25-month-old patient with complete atrioventricular septal defect and Tetralogy of Fallot underwent repair of both anomalies. The diagnosis was established preoperatively by 2D-echocardiography, cardiac catheterization and cardioangiogram, Repair was accomplished using cardiopulmonary bypass and profound hypothermia to 18C, Closing of the atrioventricular septal defect was achieved with the use of two Dacron patchs by an atrial approach alone. Infundibulectomy and outflow tract reconstruction with the transannular pericadial patch containing a monocusp were performed. Upon the postoperative evaluation by 2D-echocardiography, mitral regurgitation was absent, but a tiny dehiscence of ventricular patch and minimal tricuspid regurgitation were noticed.

• 대한전기학회논문지:시스템및제어부문D
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• 제54권6호
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• pp.383-389
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• 2005

This paper proposes a pattern classification algorithm for the defect distribution of Hard Disk Drive (HDD). In the HDD production, the defect pattern of defective HDD set is important information to diagnosis of defective HDD set. In this paper, 5 characteristics are determined for the classification to six standard defect pattern classes. A fuzzy inference system is proposed, the inputs of which are 5 characteristic values and the outputs are the possibilities that the input pattern is classified to standard patterns. Therefore, classification result is the pattern with maximum possibility. The proposed algorithm is implemented with the PC system for defective HDD sets and shows its effectiveness.

• Journal of Chest Surgery
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• 제10권1호
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• pp.106-112
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• 1977

Transposition of the great arteries is one of the commonest forms of severe congenital heart disease and produces severe cyanosis threatening survival from the day of birth. Anatomical anomalies which the aorta arises from the infundibulum of the right ventricle and the pulmonary artery arises from the outflow tract of the left ventricle make the deranged circulation. Survival is possible only if additional anomalies are present which allow mixing of the pulmonary and systemic circulations. Preoperative diagnosis as TGA was taken on the 15 day old female via the preoperative examination and the right cordioangiography. As palliative treatment for cyanosis, Blalock-Hanlon operation was performed in this patient. The results were good as 54 mmHg changed from 27 mmHg of $PO_2$ in aorta, but sudden cardiac arrest was developed in postoperative 12 hours. In order to confirm the cause of death and the cardiac anomalies, autopsy was performed on the date of death. The diagnosis of the autopsy showed; [1] Transposition of the Great Arteries. [2] Patent Ductus Arteriosus. [3] Patent Foramen Ovale. [4] Ventricular Septal Defect, 2 Muscular Type. [5] Double Ureter, Right. [6] Artificial Atrial Septal Defect. [7] Total Collapse of the left lung and Intraparenchymal hemorrhage of right lung.

• 한국생산제조학회지
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• 제18권6호
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• pp.604-613
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• 2009

Recently, researches to develop phased array ultrasonic examination techniques are proceeded to diagnose dental caries and the status of surgical operation of dental implant. Sound field analysis of phased array ultrasonic transducers were carried out in order to characterizing the ultrasonic phased array beams. The sound field of ultrasonic radiation was calculated for the sample called "gypsum-improved stone" with the similar characteristics of dental materials. Industrial phased array ultrasonic devices were utilized for the insptriion of the artificial flaws machined in the gypsum-improved stone. Dental implants were made at the pig jaw bone and defect images were confirmed for the dental implants.