• 전기의세계
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• v.45 no.8
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• pp.25-29
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• 1996

동맥에 대한 기계 역학적인 연구역사는 30년에 이르고 있다. 그 연구 성과로 말미암아 동맥의 물성 파악, 동맥의 인조화, 동맥의 의학적인 시술에 대한 공학적인 평가 분석 및 제안, 동맥의 생리학적인 현상에 대한 이해 보강, 병리 현상의 공학적인 분석 및 예고, 공학적인 현상과 조직학적인 현상에 대한 연관성 파악 및 응용등, 많은 공헌을 하고 있다. 동맥에 대한 공학적인 연구학문을 동맥역학(Arterial Mechanics)이라 한다. 동맥역학의 궁극적 분석겨로가는 동맥에 대한 물성과 혈압으로 인한 변형율과 응력에 관한 것이다. 동맥의 물성 파악은 혈류와 Mass Transport의 효과로 인한 동맥의 질병양태에 대한 해석을 돕고 있다. 또한 동맥의 병리현상과 생리현상을 이해하는 데에 변형율과 응력 분포도가 중요한 요소로 역할을 하고 있다. 동맥의 연구 방법론적 고찰의 내용은 실험이나 데이터 분석방법이 비슷하기 때문에 동맥 외의 인체의 soft tissue(피부, 심장, 근육, 눈등)에 대한 연구고찰이라고도 할 수 있다. 본 논문은 현재까지 진행된 주요한 연구를 고찰하고 동맥 역학에 대한 관심과 인식을 고취시키는 데에 그 목적이 있다.

• Proceedings of the KIEE Conference
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• 2003.07c
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• pp.1864-1866
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• 2003

최근 마이크로파 방전에 의한 고압 2-원자 분자인 InBr중기는 고연색성(high color rendering index, CRI)의 백색광 발광원으로 주목 받고 있다. 잘알려진 무전극 황전등은 최고 효율이 173 lm/W까지 시연되어 알려진 모든 인조 광원 중에서 가장 높은 효율을 보인 혁신적인 광원이다. 이에 비해 InBr방전등은 무전극 황전등에 비해 효율은 떨어지지만 거의 완벽한 CRI(95이상)를 보이기 때문에 차세대 projection display의 발광원으로 대두되고 있다. 본 논문에서는 원편파 마이크로파 이용하여 무전극 InBr방전등의 입력전력의 변화와 InBr의 양 변화에 대한 특성(휘도, 상관색온도, 스펙트럼, 등)에 관한 실험결과를 보고한다.

• Journal of Biomedical Engineering Research
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• v.15 no.2
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• pp.143-150
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• 1994

Wall shear rate or stress is believed to be a major hemodynamic variable influencing atherosclerosis and artery-graft anastomic intimal hyperplasia. The purpose of this study is to verify the effects of radial wall motion, artery-graft compliance and diameter mismatch, and impedance phase angle on the wall shear rate distribution near an end-to-end artery-graft anastomosis model. The results show that radial wall motion of the elastic artery model lowers the mean wall shear rates under pulsatile flow condition by 15 to 20 % comparing to those under steady flow condition at the same mean flow rate. Impedance phase angle seems to have small effects on the mean and amplitude of the wall shear rate distribution. In order to study the effects of compliance and diameter mismatch on the wall shear rates, two models are studied-Model I has 6% and Model I has 6% and Model II has 11% smaller graft diameter. Divergent geometry caused by diameter mismatch near the distal sites reduces the mean wall shear rates significantly, and this low shear region is believed to be prone to intimal hyperplasia.

• Proceedings of the KIEE Conference
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• 2001.07d
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• pp.2289-2291
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• 2001

In this paper, a novel sliding surface is proposed by defining a novel virtual state. This sliding surface has nominal dynamics of an original system and makes it possible that the Sliding Mode Control(SMC) technique is used with the various types of controllers. Its design is based on the augmented system whose dynamics have a higher order than that of the original system. The reaching phase is removed by using an initial virtual state which makes the initial sliding function equal to zero.

• Journal of Chest Surgery
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• v.32 no.9
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• pp.844-846
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• 1999

Chronic irritation to arterial wall by foreign material may give rise to delayed vascular injury. A 50 years old male patient with kyphoscoliosis had undergone fixation of orthopedic Cotrel-Dubousset(CD) rods and screws. Fourteen months after that surgery, a false aneurysm of the descending thoracic aorta associated with pulsating hematoma in the muscular chest wall developed. The false aneurysm was managed by resecting the diseased aortic segment and replacing the vascular graft.

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2014.10a
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• pp.105-107
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• 2014

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 1999.04a
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• pp.2-2
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• 1999

액체추진제 로켓엔진에서 분사기의 미립화 및 혼합 특성과 그에 따른 연소 특성은 성능과 안정성을 결정하는 중요한 파라미터이며 분사기는 제한된 설계 조건하에서 최대의 열방출율을 발휘하도록 설계되어야 한다. 여기서 연소효율은 연료와 산화제의 혼합특성과 충돌 분무의 미립화의 정도에 의해 결정되므로 충돌 분무 유동성의 혼합, 미립화 특성과 이에 따른 인조성능 특성을 명확하게 밝힘으로써 최대 엔진성능을 위한 설계가 가능하게 된다. 분사기의 설계에는 분사요소형태, 분사공의 형상 및 유동시스템 등이 포함되며 특히 분사요소 형태의 선택에는 추진제, 연소실냉각방법, 연소실 형상, 자동조건 및 엔진의 수명 등이 중요한 제한조건으로 고려된다. 이런 형태의 분사 요소들 중, 충돌형 분사기는 저장성 추진제를 사용하는 중, 저추력의 액체추진제 로켓엔진에 주로 사용된다. 이 분사형태는 미립화 성능이 높지 않고, 분사공 직경 및 운동량비에 따른 혼합성능이 만감하며 blow apart 등에 의한 열부하 혹은 안정성에 대한 문제가 있으나 양호한 혼합효율, 신뢰성과 제작의 용이함으로 인하여 광범위하게 사용된다.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.11a
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• pp.135-136
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• 2019

Recently, as the interest in environmental issues increases, the construction industry needs to recycle blast furnace slag, circulating fluidized bed Combustion fly ash, etc. to solve industrial by-products, and to develop artificial stone. In this study, the strength characteristics based on blast furnace slag according to the addition rate of alkali stimulant NaOH are investigated. The experimental results showed that the flexural and compressive strengths increased with the addition of alkali stimulants. Based on these results, it will be presented as a basic research data for the manufacture of artificial stone and will be tested later.

• MISULJARYO - National Museum of Korea Art Journal
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• v.100
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• pp.112-138
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• 2021

This paper mainly analyzes the records titled 'Shijujil(施主秩)' from the Bokjangs of each of the Rocana and Shakyamuni statues enshrined as wooden seated Vairocana Buddha Triadcomposed of Vairocana(center), Rocana(right), and Shakyamuni(left) at the Daeungjeon Hall of Hwaeomsa Temple in Gurye. The Shijujil from the Shakyamuni statue was recovered through Bokjang investigation in September 2015 and has been kept in the museum of Hwaeomsa as an undisclosed relic. After the discovery of the Shijujil from the Rocana statue through an Bokjang investigation in July 2020, both of the Shijujils were only officially released through the special exhibition 'Grand Hwaeomsa Temple in Jirisan Mountain' in September 2021. Existing documents recording on the creation of Buddha statues in the 17th century are in the form of sheets or rolls. However, the Shijujils take the form of simple stitched booklets. The Shijujil from Rocana consists of 19 chapters and 38 pages in one book, and the Shijujil from Shakyamuni consists of 11 chapters and 22 pages in one book. The contents of the Shijujils consist of the purpose of the Buddha statue creation, the creation date, the year and place of enshrining, the names of the statues, the people in charge and their roles, the sculptors, the list of items donated, and the list of the contributors. In addition, the list of monks who were staying at Hwaeomsa Temple at that time are also recorded, so the Shijujil is like a time capsule that tells the situation of Hwaeomsa Temple about 400 years ago. According to the records of the Shijujils and the Writing on the wooden pedestal of Rocana, the Vairocana Triad began to be in March 1634(12th year of King Injo) and was completed in August of that year, and was enshrined in the Daeungjeon Hall in the fall of the following year. It is very important to confirm that the Vairocana Buddha Triad of Hwaeomsa was created in 1634. Since studies on the reconstruction of Hwaeomsa Temple in the 17th century and the roles of Byeokam Gakseong have been mainly based on 『湖南道求禮縣智異山大華嚴寺事蹟』 written by monk Haean in 1636, it has been estimated that the wooden seated Vairocana Buddha Triad was created in 1636. However, it is now known that the Virocana Buddha Triad was created in 1634. The Shijujils are also a good source of information about Byeokam Gakseong who played a pivotal roles in the reconstruction projects of Hwaeomsa Temple in the 17th century. He played leading roles in rebuilding the East Five-story Stone Pagoda(1630), in creating the wooden seated Vairocana Buddha Triad(1634), and in producing the Yeongsanhoe Gwaebul(1653, Hanging Scroll Painting depicting the Shakyamuni preaching). It is also very important that the Shijujils are records that can reveal the relationship between Byeokam Gakseong and royal family of Joseon Dynasty in the 17th century. The Shijujils from Rocana and Shakyamuni are the first documents ever discovered in which the names of royal family members, such as Uichanggun(Gwang Lee, son of King Seonjo), Ikseong Shin(son-in-law of King Seonjo), and Crown Prince Sohyeon(son of King Injo) are recorded in detail in relation to the production of Buddha statues. The Shijujils from Rocana and Shakyamuni contain specific information about the production of the wooden seated Vairocana Buddha Triad in the 17th century, such as the year of production of the Buddha statues, the role of Byeokam Gakseong, and the relationship between Byeokam Gakseong and the royal family, so it is of great value not only for art history but also for historical studies of Hwaeomsa Temple.

• Journal of Chest Surgery
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• v.30 no.4
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• pp.378-382
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• 1997

To evaulate the effectiveness and risk factors for shunt failure of the Blalock-Taussig shunt in neonates, we analyzed the 21 neonates who were undergone Blalok-Taussig shunt operation at Dong-A University Hospital from December 1991 to Feburary 1996. We evaluated operative mortality, patency of the shunt. and distortion of pulmonary artery. We also determined the risk factors for the shunt failure. Age at operation was from 1 day to 30 days(mean 11.7 days). We ghts were 2.4 to 4.5kg(mean 3.1 kg). The underlying lesions included severe tetralogy of Fallot with pulmonary stenosls or atresia(N=11) and single ventricle varieties with. pulmonary stenosis or atresia(N=10). Prostaglandin El was given in 13 neonates prior to operation. The mean preoperative(prior to prostaglandin El therapy) and postoperative arterial oxygen tension were 30.1 mmHg and 46.3 mmHg respectively(P(0.01). The shunt was performed through a left thoracotomy in 11 patients and through a right thoracotomy In 10. A 5 mm graft was used in 15 patients and a 4 mm graft in 6 patients. The incidence of early shunt occlusion was 9.5%(2 patients). The hospital mortality was 9.5%(2 patients with early shunt occlusion). Univariate analysis revealed that body weight of 2.6 kg or less(p=0.021), pulmonary artery size of 3mm or less(p=0.008), and 4 mm graft (p=0.021) were risk factors predictive of early shunt failure. The patency rate of the shunt in hospital survivors was 100% at mean ollow-up of ll.3 months(There was not death or reoperation related to shunt failure). 10 patients were catheterized during postoperative follow-up. There was no significant distorsion of pulmonary artery. So we concluded that the modified Blalock-Taussig shunt in neonates was excellent in the hospital survivors.