• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 추계학술대회논문집 II
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• pp.1132-1137
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• 2001

The smart foam that is first proposed by Fuller(2) is not applicable to active noise control in a duct having flow. Thus. this paper presents the ring-type smart foam as an alternative. The ring-type smart foam consists of polyurethane acoustic foam of lining shape and PVDF film embedded along the mid-surface of the foam lining. A feedforward adaptive filtered-x LMS controller is used to minimize the signal from the error microphone. To enlarge quiet sound region. two error microphones are used to update system modeling filter (SIMO method). Sound intensity control using the ring-type smart foam is also discussed

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 춘계 학술발표회
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• pp.551-560
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• 2009

Introduced was a new anti-corrosive method with improved ease of construction, economy, and durability that could be applicable for steel-composite drilled shaft. The feasibility and economy of sea-water-resistant steel was evaluated under the assumption that it was to substitute carbon steel for steel casing of drilled shaft foundation as a load carrying structural member not just as a sacrifice casing, and that anti-corrosive protection measures as required by the domestic standards was applied. Sea-water-resistant steel was found to cost 30% to 55% more, depending on pile diameter and the type of applied anti-corrosive measures, than carbon steel for the service life time of 70 years: 50% to 90% more for 100 years of service life.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 춘계학술대회논문집
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• pp.426-430
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• 2001

Conventional smart foam is not applicable to active noise control in a duct having flow. Thus, this paper presents a ring-type smart foam as an alternative. The ring-type smart foam consists of polyurethane acoustic foam of lining shape and PVDF film embedded in the foam. The embedded PVDF element acts as an actuator to reduce noise at lower frequencies and the foam absorbs noise at higher frequencies. A feedforward adaptive filtered-x LMS controller is used to minimize the signal from the error microphone. Experiments are executed to reduce broadband and tonal noise.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집B
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• pp.641-645
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• 2001

In this paper, it is discussed that active noise control in a circular duct using smart foam. Firstly, it is demonstrated that the potential of the conventional smart foam, proposed by Fuller, for active noise control in a duct. Conventional smart foam is not applicable to active noise control in a duct having flow. Thus, this paper presents a ring-type smart foam as an alternative. The ring-type smart foam consists of polyurethane acoustic foam of lining shape and PVDF film embedded in the foam. The embedded PVDF element acts as an actuator to reduce noise at lower frequencies and the foam absorbs noise at higher frequencies. A filtered-x LMS controller is used to minimize the signal from the error microphone. Experiments are executed to reduce broadband and tonal noise.

• Macromolecular Research
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• 제8권4호
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• pp.179-185
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• 2000

Generally vascular grafts with a relatively large inner diameter (> 5 mm) have been successfully employed for replacement in the human body. However, the use of small diameter grafts is limited, because these grafts rapidly occlude due to the thrombosis. The ideal blood-contacting surface of a prosthesis would be an endothelial cell (EC) lining, because the confluent monolayer of healthy ECs that culture natural blood vessels represents the ideal nonthrombogenic surface. For vascular graft application, the stable EC adhesion on surface under How conditions is very important. In this study, the adhesive strength of ECs attached on polymer surfaces coated with collagen type IV (Col IV), fibronectin (Fn), laminin (Ln), and treated with corona was investigated onto polyurethane (PU) films. The EC-attached PU surfaces were mounted on parallel-plate flow chambers in a How system prepared for cell adhesiveness test. Three different shear stresses (100, 150, and 200 dyne/㎠) were applied to the How chambers and each shear stress was maintained for 120 min to investigate the effect of shear stress and surface treatment condition on the EC adhesion strength. It was observed that the EC adhesion strength on the surface-modified PU films was in the order of Ln≡Fn > Col IV > corona 》 control. More than 70% of the adhered cells were remained on surface-modified PU surface after applying the shear stress,200 dyne/㎠ for 2 hrs, whereas the cells were completely detached on the control PU surface within 10 min after applying the same shear stress. It seems that the type of adsorbed proteins and hydrophilicitv onto the PU surfaces play very important roles for cell adhesion strength.

• Journal of Chest Surgery
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• 제29권4호
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• pp.373-380
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• 1996

소구경 인조혈관의 생 체적합성 향상은혈전생성을막는것이 해결해야 할 문제점이다. 정상혈관의 혈 관내피세포는 항상 정상기능 혈관을 유지하게 하는 중요한 역할을 한다. 본 연구의 목적은 다공성 폴리 우레탄소구경 인조혈관의 생체적합성을 높이기 위한 방법을 개발하는 것인데,혈관내피 세 포화를 위해 섬유아세포에서 생성분비되는 세포외기 질이 어느정도 유용한 지를 알아보기 위한 것이다. 방법 : 인조혈관골격은 폴리우레탄을 이용하여 직경 3mm와두께 0.3mm,길이 6cm로 가공하였고,체 중 15kg되는 잡종개의 경정맥에서 얻은 섬 유아세포를 배양하여 폴리우레탄 튜브벽에 부착배양하여 세 포외기질층을 형성시켰다. 그다음 개의 경정맥에서 내피세포를 분리배양하여 충분한 세포를 인조혈관 내면을 세포 배양한 자가혈관내피세포로 증착시키서 자연혈관과 비슷한 형태의 3층 구조 인조혈관을 만들었다 혈관내퍼세포가부착된 직경 3rnm의 소구경 인조혈관을 길이 km로잡종견의 경동맥에 자가 이식하였고, 이식후 3주, 6주에 이식한 인조혈관을 적출하여 조사하였다. 동물실험의 대조군으로는 시 판되고 있는 직경 4mm 길이 6cm PTFE 혈관을 사용했다. 결\ulcorner: 개의 경정맥내피세포를 분리 배양하여 직경 3mm폴리우레탄 인조혈관 내벽을 내피세포화 하 는데는 섬 유아세포를 먼저 배양하여 생성된 세포외 기질을 기반으로하여 혈관내피세포를 부착시켜 생 체적합성이 개선된 인조혈관을 개발할 수 있다. 동물실험한 3마리의 개에서 내피세포 부착 인조혈관 3 개와 다공성 폴리우레탄 인조혈관 3개를 이식한 결과는 내피세포 부착인조혈관에서 33%의 개방성이 있었으나 혈전형성도 관찰되 었다. 개에 이식된 혈관내피세포화 인조혈관을 6주안에 제거한 혈관에서 혈전이 생겨 폐색되기는하였지만 앞으로내피세포의 생육성 향상으로 혈전방지 소구경 인조혈관의 개발에 새로운 방법이 될 것으로 판단되었다.여 주었다. 우심유출로확장술을 받은 환자가 1명 있었다. 전반적으로 14명의 환자에서 양호한 경과(New York Heart Association functional class I~II)를 보이고 있다.er$인문지리학 원리$\lrcorner$가 나왔다. 1970년대 중반이후 인문지리의 실증-계량적 분석에 대한 비판이 일어나기 시작했고, 그런 중에 1980년대 초반에 인문지리 학 방법론상 중요한 2개의 대립적 논문 (김인의 공간지리학 옹호와 최기엽의 장소이해 옹 호)이 나왔다. 그후 방법론상의 논의가 5-6편 나와 오늘에 이르렀다. $\ulcorner$인문지리조사법$\lrcorner$ 교 재가 역시 비포괄적이나마 국내 최초로 출간된 것은 1988년 (조동규)의 일이다. 포괄성이 훌 륭한 인문지리학 체계서의 출간이 절실히 요망된다. 방법론에 있어서는 공간-계량적 입장과 지역-종합-해석적 입장간의 조화와 상호보완이 있어야 할 것이다.pacts, competitive advantages of Korean agricultulal products, and environmental impacts of agricultural restructuring. Research in industrial geography has remarkably progressed since the 1980s. Locational changes, regional industrial structure and formation of industrial region were the major topics of interest in the research of industrial geography in Korea before 1980. Since the early 1980s, in addition

• 한국의류학회지
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• 제40권5호
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• pp.844-854
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• 2016

In order to understand the current state of production and pattern design of circular knitted jackets, this study selected 11 female clothing brands based from the "2012/2013 Korea Fashion Brand Yearbook" and interviewed the staff in charge of patterns at the companies. Polyester and polyurethane were found to be synthesized and used for the outshell of circular knitted jackets, alternatively natural fabric cotton or wool were synthesized with rayon. As for the structure of circular knitted materials, Ponte Di Roma knitting structure (a modified form of a double knit) was most often used. Surveying the use pattern and the parts for padding cloth, six responded that they used elastic padding cloth. As for circular knitted jackets with inner lining, elastic padding cloth was attached to all parts (front, back, side panel, and collar - except for sleeves) of the basic bodice pattern. Eight responded that they did not use a basic pattern when designing a pattern, which exceeds the majority. All respondents answered yes to the question on if there is any difference in designing a pattern for a woven jacket and a circular knitted jacket. It was found that they designed a pattern that considered shrinkage and elongation, which are the features of circular knitted fabric. Shrinkage and elongation were the features of a fabric material most considered when designing patterns for a circular knitted jacket.