• Proceedings of the Korea Institute of Convergence Signal Processing
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• 2000.08a
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• pp.201-204
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• 2000

본 논문에서는 기존의 칼라 항상성(color constancy) 알고리즘을 기반으로 한 새로운 영상 복원 방법을 제안한다. 이 방법은 인간의 시각 특성을 선형 모델로 표현한 칼라 항상성 모델을 이용한다. 칼라 항상성 모델에서 가장 중요한 과정은 영상의 광원을 추정하는 것이다. 이론 위하여 영상에서 명도 값이 가장 큰 화소의 값을 이용하며, 이 값을 각 수광체(photoreceptor)의 응답으로 대체한다. 추정된 광원을 이용하여 만들어진 영상을 일정한 비율로 스케일링하여 영상을 복원한다. 실험을 통하여 제안한 항법으로 영상 복원이 잘 됨을 알 수 있었다.

• Journal of Industrial Technology
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• v.30 no.A
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• pp.45-47
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• 2010

In legacy e-learning web service, as deployed contents are changed, web services should be changed together. In addition, it can not coordinate and manage the various e-learning services recently emerged. In this paper, an e-learning platform based on Service-Oriented Architecture (SOA) is proposed to solve these problems. We design and implement an e-learning system based on Service abstraction layer concepts. The implemented system can provide the new e-learning services within short development periods.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.6
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• pp.1259-1265
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• 1997

We investigate depth measurement error of a range finder based on triangulation method. Geometric analysis resulted in intuitive understanding of the error sensitivity. We show that the depth error is propostional to the distance between the object andthe camera. The measurement value has the highest accuracy when the line connecting the focal point of the camera and the object is perpendicular to the line joining the object and the light source of herange finder. Also we analyze the error using a perturbation method and verify that the results are identical through an experiment.

• Journal of Chest Surgery
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• v.23 no.5
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• pp.922-928
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• 1990

Treatment of patients with esophageal carcinoma remains disappointing. Fewer than 20% *of patients with esophageal carcinoma treated with curative intent by surgery and radiation therapy will be alive at 5 years. Fifty five patients underwent treatment for carcinoma of the esophagus and cardia which retrospective clinical study done between January 1983, and December, 1989 in Department of Thoracic and Cardiovascular Surgery, National Medical Center, Seoul, Korea. There were 48 men. 7 women and the mean age was 56.2 years[range, 38 to 78 years]. The most frequent preoperative findings included dysphagia[46 cases], weight loss[33 cases] and substernal pain[19 cases]. 19 cases[34.5%] were underwent resectional surgery, which was total esophagectomy with esophagogastrostomy[ 5 cases], with colon interposition[3 cases], lower esophagectomy with esophagogastrostomy [10 cases], with total gastrectomy and esophagojejunostomy [1 case]. The operative mortality was 15.8%[3/19] and causes of death were respiratory failure in 2 cases, and 1 case of sepsis. Palliative procedures, such as feeding gastrostomy and jejunostomy[14 cases], bypass surgery without resection[ 4 cases], radiation therapy[ 3 cases] were done.

• Journal of Chest Surgery
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• v.23 no.5
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• pp.976-986
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• 1990

We experienced 12 patients with the abdominal aortic aneurysm during last 31 years [Dec. 1958 \ulcornerSep. 1989]. Among them, 10 patients were reviewed. They were all male. The age ranged from 34 to 80 years with the mean age of 59.4 years. The etiology of the aneurysm was atherosclerotic in 8, mycotic in 1, and aortitis in 1. The location of the aneurysm was infrarenal in 8, and suprarenal in 2 cases. Aneurysmectomy and Dacron Y-graft interposition in 8 cases, and lease with Teflon Y-graft were made. In another 1 case, long thoracoabdominal bypass surgery was made. The operative mortality was 30%[3cases]. The postoperative complications were respiratory complications[3cases], acute renal failure[2cases], bleeding[lease], mechanical ileus[ lease], and peritonitis[lease].

• Journal of Chest Surgery
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• v.22 no.6
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• pp.1106-1110
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• 1989

We experienced 53 cases of tuberculous peripleural abscess, which had been proved by histopathological study, from Jan. 1980 to Dec. 1988. In 53 cases of abscesses, mean age was 25 years which was ranged from 1 year and 3 months old boy to 61 years old female [Male: Female=1.4: 1]. The location of the lesion was mainly right-sided [62%] and lateral predilection [53%]. In most of cases [85%], there was history of pulmonary tuberculosis and pleural thickening, but negative mycobacterial culture in the pus. Rib involved cases, confirmed by histopathologic examination, were 38.9% of all cases, which were all removed during operation. Combined pathologic lesions were all cleared at the same time, principally. There were 8 cases of recurred, of which at the same sided, 7 cases and contralateral sided, 1 case.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.23 no.9A
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• pp.2165-2172
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• 1998

Existing premises telecommucation wiring ad been installed for efficient telephone service. But premises wiring is currently ready to be reused as media for wideband digital services and Fiber-to-the-curb architecture. Electrical properties of premises wiring link have not characateized above frequencies for voice service. Accurte measurement of these characteristics are exssential for studies fof wideband ditital transmission system. On the other hand, the transmission qualities of premises wiring have been known to be worst in telecommunications access networks. So the knowledge of premises wiring sturucture as well as electrical properties is needed to improve the performance of premises wiring. In this paper, the structure of premises wiring is described in detail and electrical characteristics (characteristic impedance, SRL, attnuation, NEXT) about premises cables and stelecommucations link of representative apartment complex sare measured and naalyzed ove r16MHz range which is UTP Cat3 bandwidth.

• Proceedings of the Korea Information Processing Society Conference
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• 2001.10a
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• pp.809-812
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• 2001

내용에 기반한 동영상 검색에서, 하나의 장면을 나타내는 대표 프레임을 자주 이용한다. 이를 위해 동영상의 장면전환을 검출하는 기술이 필요하며, 일반적으로 칼라 히스토그램 비교방법이 많이 쓰인다. 그러나 이는 급격한 밝기변화에 민감하고 칼라 히스토그램 분포가 비슷한 부분의 장면전환을 놓칠 수 있다는 단점이 있다. 본 논문에서는 칼라 히스토그램 비교방법과 엔트로피를 복합적으로 이용하여 이러한 단점을 보완하고자 하였다. 실험을 통해 제안한 방법은 기존의 칼라 히스토그램을 이용한 방법보다 성능이 우수함을 알 수 있었다.

• Journal of Chest Surgery
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• v.22 no.3
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• pp.448-455
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• 1989

Till June 1988, We experienced 3 cases of single atrium at Dept. of Thoracic k Cardiovascular Surgery of National Medical Center. Case 1 was 26 years old female, and had single atrium associated with partial cleft in mitral anterior leaflet and PAPVC. Atrial septation with Dacron patch and MVR [I-S, 31 mm] were done, followed by TAP, De Vega. Postoperative course was good, OPD follow-up for about 4 years with normal physical activity and ordinary working. Case 2 was 4 years old female with single atrium alone. Atrial septation with pericardial patch. Good postoperative course and OPD follow-up for about 2 years with appropriate physical growth. Case 3 was 22 years old female, single atrium with complete cleft in the anterior and posterior mitral leaflet, and septal tricuspid cleft were identified. Atrial septation with polystan bovine pericardial patch and repair of mitral anterior cleft. Postoperatively, residual regurgitation of mitral and tricuspid valve, but tolerable in some limitation of physical activity.

• Journal of Chest Surgery
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• v.21 no.4
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• pp.787-792
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• 1988

Esophageal duplication constitute about 10% of all the mediastinal tumor and relatively rare condition. We have experienced one case of esophageal duplication which was found 2 years previously by radiologic study of chest, as mediastinal mass, in 37 years old male. He had neither clinical manifestations nor physical findings leading to the surgical discovery of the duplication. During the last 2 years, the size k location of the mass were stationary in character. Operative therapy of complete excision performed without surgical complication. On microscopic study, the lining cell of inner wall of cyst. Noted pseudostratified ciliated columnar epithelium with smooth muscle.