• Title/Summary/Keyword: 보존형

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Thermal Characteristics of Nutrient Solution and Root Media in Recycled Soilless Culture Systems (순환형 무토양재배시스템 양액 및 배지의 열적 특성)

  • 손정익;장진택;이병일
    • Proceedings of the Korean Society for Bio-Environment Control Conference
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    • 1997.05a
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    • pp.59-61
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    • 1997
  • 무토양재배시스템은 가급적 경량화이면서 집약적인 형태를 가지며, 환경보존차원을 위하여 밀폐형 순환식 재배시스템이 중시되고 있다. 무토양재배시스템은 DFT에서 NFT나 고형배지로 갈수록 외기의 환경변화에 대하여 비교적 근권부근의 환경변화가 크기 때문에 노출되어 있는 뿌리에 영향을 미치는 것으로 사료된다. (중략)

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Status of High-Performance Stirling Engine Development and Application (고효율 스터링 엔진의 개발 및 응용 현황)

  • 오박균;김창기
    • Journal of the korean Society of Automotive Engineers
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    • v.9 no.6
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    • pp.1-7
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    • 1987
  • 스터링 엔진은 1816년 로버트 스터링에 의해 발명된 밀폐형 외연기관이다. 초기에는 왕복형 증기기관과 더불어 구미제국에 널리 보급되었으나, 실용화 기술의 부족으로 인한 잦은 고장과 가솔린 및 디젤엔진의 발명으로 인해 자취를 감추었다. 그 후 1938년 네덜란드의 필립스사(Philips Co.)에 의해 연구가 재개되고, 간헐적으로 진행되다가 최근에 연료의 다양화, 에너지절약, 환경보존 등에로의 강한 요구와 재료기술 및 생산기술의 진보로 인하여 이 엔진이 다시 주목되어 구미, 일본 등에서 연구 개발되고 있다. 미국에서는 1978년부터 정부적 차원에서 개발을 시작하여 일부는 상용화되어 있고, 일본에서는 1982년 이래로 계속 개발을 수행하고 있고, 그 외에도 유럽의 여러 나라들에서도 활발한 연구가 진행되고 있다.

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Flow Cytometric Analysis of Endothelial Cell Viability in Arterial Allograft (동종동맥판 혈관내피세포의 생육성 평가에 관한 연구)

  • 임창영;홍은경
    • Journal of Chest Surgery
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    • v.30 no.6
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    • pp.553-558
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    • 1997
  • Arterial allografts have known advantages over prosthetic vascular conduit for treatment of heart valvular disease, congenital heart disease and aortic disease. Cell viability may play a role in determining the longterm outcome of allografts. Endothelial cell is one important part in determining the allograft viability. To evaluate the viability of endothelial cells using current allograft preservation technique, porcine heart valve leaflets and arterial wall were subjected to collagenase digestion. Single endothelial cell suspension was labeled with GSA-PITC(Griffonia simplicifolia agglutininfluorescein isothiocyan te), a vascular, endothelial cell specific marker. The cell suspension was washed and incubated with Pl(Propidium iodide), which does not bind with viable cells, Endothelial cell viability was evaluated by calculating the percentage of GSA-FITC(+) and Pl(-) group using flowcytometric analysis. Allografts were treated with $4^{\circ}C$ antibiotic solo!ion for 24 hours for sterilization. After this, half of allografts were stored in $4^{\circ}C$ RPMI 1640 with HEPES buffer culture medium with 10% fetal bovine serum for 1 to 14 days(Group I). Another half of allografts were cryopreserved with a currently used technique (Group II). During the procurement and sterilization of arterial allografts, 22.8% and 24.4% of endothelial cell viability declined, respectively. In Group I, 11.9% of endothelial cell viability declined further steadily during 14 days of storage. In Group II, 13.7% of endothelial cell viability declined. These results show that largest loss of endothelial cell viability occurs during the nitial process. After 14 days of arterial allograft storage under $4^{\circ}C$ nutrient medium or cryopreservation, about 40% of endothelial cell viability is maintained. There were no differences between the endothelial cell viability from aortic valve leaflet, pulmonic valve leaflets, aortic wall and pulmonic wall.

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A Case Study on the Restoration to Designated State Based on the Scientific Analysis of Gold Threads of Gwanghwadang-Wonsam (광화당 원삼의 금사 분석과 원형복원 사례)

  • An, Boyeon;Lee, Ryangmi;Lee, Jangjon
    • Journal of Conservation Science
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    • v.37 no.2
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    • pp.144-153
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    • 2021
  • Gwanghwadang-Wonsam was designated as National Folklore Cultural Heritage No. 52 in 1979, it is in good condition. However, a problem is the attached a phoenix insignia badge that did not exist when it was designated recently. As it became known as the only purple Wonsam artifact with "phoenix insignia", raising the need for its conservation. In this regard, scientific analysis was required to correct misinformation about designated cultural assets and restore the original designated state by analyzing the history of the Gwanghwadang-Wonsam, other relics of the phoenix insignia and its making design patterns. An X-ray fluorescence analysis was used to confirm that the Phoenix insignia's metal threads were titanium-plated silver. Phoenix insignia using titanium-plated gold thread was not identified in Gwanghwadang-Wonsam photographs in 1986, and the TiN-type membrane plating method was used in various industries in the 1990s, which can be estimated to be attached in the early and mid-1990s. Especially, the scientific analysis results from the X-ray fluorescence analysis in this study provide key evidence for conservation processing. This study demonstrates the importance of investigating relics and similar artifacts in the conservation process of inherited relics and as a precedent for restoration that corrects misinformation about designated cultural properties.

Effects of Flushing, Preservation and Reperfusion in the Canine Transplanted Lung Tissue (관류, 보존 및 재관류 과정이 이식된 개의 폐조직에 미치는 영향)

  • Lim, Young-Keun;Park, Chang-Kwon;Kwon, Kun-Young
    • Tuberculosis and Respiratory Diseases
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    • v.46 no.4
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    • pp.512-522
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    • 1999
  • Background: Due to the paucity of suitable donor organs for lung allotransplantation, a number of techniques have been developed to improve the lung preservation. Ultrastructural studies of the morphologic changes of the flushing, preservation and reperfusion injury in donor lungs have rarely been reported. Methods: Adult dogs (n=46) were matched as donors and recipients for the single lung transplantation. The donor lungs were preserved after flushing with preservation solution and transplanted after 20-hours of preservation at $10^{\circ}C$. Ultrastructural features of the lung were examined after flushing, preservation and 2 hours after lung transplantation (reperfusion) respectively. Results: Electron microscopy after flushing showed focal alveolar collapse and mild swelling of type I epithelial cells. After preservation both type I epithelial cells and endothelial cells were swollen and destroyed focally. The endothelial cells showed protrusion of tactile-like structures into the lumina, blebs or vacuoles of the cytoplasm After reperfusion the lung tissue showed fibrin material in the alveoli, prominent type I epithelial cell swelling with fragmented cytoplasmic debris and marked endothelial cell swelling with vacuoles or tactile-like projections. The alveolar macrophages showed active phagocytosis. Scanning electron microscopic examination of the pulmonary parenchyma showed focally alveolar collapse and focal consolidation after the preservation and more prominent changes after the reperfusion procedure. The lungs preserved with low potassium dextran glucose solution, with additional prostaglandin $E_1(PGE_1)$ and verapamil(VP) showed relatively well preserved ultrastructures compared with those which were preserved with modified Euro-Collins or University of Wisconsin, and with additional $PGE_1$ and/or VP. Conclusion: The ultrastructural changes associated with flushing were mild in severity, the donor lungs were injured during the preservation, and further damage was occurred during the reperfusion. The reperfusion injury resulted in prominent pulmonary parenchymal alterations with a pattern of acute lung injury.

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Computed tomography investigation of the three-dimensional structure and production method of White Porcelain Water Dropper with Openwork Lotus Scroll Design and Eight Trigram Design in Cobalt-blue Underglaze (CT 조사를 통한 청화백자투각연당 초팔괘문연적의 3차원적 구조와 제작방법에 대한 고찰)

  • Na, Ahyoung;Hwang, Hyunsung
    • Conservation Science in Museum
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    • v.25
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    • pp.1-8
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    • 2021
  • This study investigated White Porcelain Water Dropper with Openwork Lotus Scroll Design and Eight Trigram Design in Cobalt-blue Underglaze (hereinafter, the "water dropper") in the collection of the National Museum of Korea using computed tomography (CT). A replica was produced to examine both the structure and its original production method. The CT scanning identified no joint lines or pores in the clay, which suggests that the body (the lower part of the water dropper) was shaped in a single piece using a mold and was then matched with a mold-formed lid (the upper part of the water dropper). The inner container of the body portion was roughly trimmed with a bamboo knife so that its upper surface could be securely attached to the bottom of the lid and prevent any leakage in the joined surface. It appears that the inner container for storing water was made first in a cylindrical shape that met the unit of quantity used at the time and could be easily formed by molding. It was transformed into a trapezoid shape during the process of combining it with the lid. A cylindrical inner container was reproduced using silicon 3D printing to compare its capacity with that of the original inner container. The comparison revealed that the reproduced container had a capacity of 152.5㎖, whereas the original container holds approximately 168.6㎖, a figure similar to three hop (around 174㎖) in Joseon-period units of quantity. Since the capacity of the cylindrical inner container corresponds to a known measure from the late Joseon dynasty, it is likely that the water dropper was originally produced to contain a cylindrical inner container.

Applied research in formal verification of certificates of airworthiness and aviation software design phase (항공소프트웨어 설계단계와 감항인증에서의 정형검증 적용연구)

  • Jang, JoonHa;Choi, Jinyoung
    • Annual Conference of KIPS
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    • 2016.10a
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    • pp.433-435
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    • 2016
  • 기술의 발전에 따라 첨단무기체계인 군용항공기는 전투임무 수행시 내장형소프트웨어(Embedded Software)를 통해 기체내의 항공전자 장치, 항법장치, 조종장치 등의 물리적 기계적 움직임을 제어하고 있으며, 내장형 소프트웨어의 비율은 점점 증가하고 있다. 기체의 물리적 기계적 움직임이 내장형 소프트웨어에 의해 제어 되기 때문에 군용항공기의 전투능력 보존과 국방 목적의 수행을 위해선 먼저 내장형 소프트웨어 고유의 특성을 만족하고, 나아가 소프트웨어 안전성, 신뢰성, 보안성을 확보하는 것이 필요하다. 본 논문에서는 설계 단계에서 스케줄성에 대해 정형검증 하여, 내장형 소프트웨어의 실시간성, 결정성, 생존성을 보증하고, 이러한 과정을 통해 전체적인 소프트웨어 안전성, 신뢰성, 보안성을 향상시키는 방안을 연구하며, 추가로 2011년 발표된 항공 소프트웨어 표준인 DO-178C에서 요구하는 정형검증을 적용한 국내 감항인증 표준 제정의 확대방안을 연구한다.

The Characteristics of $\Delta$-shaped Filter for Full Screen Display on the FPD (FPD상에서 전화면 디스플레이를 위한 $\Delta$-형 필터의 특성)

  • 조화현;최철호;권병헌;최명렬
    • Journal of Korea Multimedia Society
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    • v.3 no.2
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    • pp.184-191
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    • 2000
  • In thid paper, we have analized the characteristics of $\Delta$-shaped filter based on preceeding study. The algorithm of $\Delta$-shaped filter for full screen display has been discussed including their edge-preserving characteristics and computaion complexity compared with the conventional algorithms. PSNR has been employed to compare the proposed method to the conventional algorithms. The proposed algorithm has been implemented using Synopsys VHDL tool. In addition, the features and trade off of the $\Delta$-shaped filter have been discussed.

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제주도의 기생화산의 형성과 분포에 관한 연구

  • 이수진
    • Journal of the Speleological Society of Korea
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    • v.6 no.7
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    • pp.8-14
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    • 1981
  • 본 연구 대상지역인 제주도는 신생대 제3기말에서 제4기에 걸쳐 형성된 화산도로 비교적 형성시기가 새롭고 침식이 미약하여 화산 원지형을 잘 보존하고 있어 화산지형 연구에 매우 적합한 지역이다. 본도에서는 주화산체인 한라산과 400여개에 달하는 기생화산으로 되어 있다.(중략)

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예비생산능력을 사용하는 납기확약 성과비교

  • 심병태;임석철
    • Proceedings of the Korea Society for Simulation Conference
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    • 2000.11a
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    • pp.41-48
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    • 2000
  • 산업재 생산업체에서 모든 주문의 납기를 확약해 주면서도 중요 고객사의 긴급주문에 대응하기 위해서는 생산능력의 일부를 예비로 보존하는“예비생산능력” 방식을 운영할 필요가 있다. 본 연구에서는 24시간 연속생산형 단일설비 장치산업에서 예비생산능력을 운영할 때 납기를 확약해주는 알고리즘과 사용가능한 대안들에 대하여 그 성과들을 시뮬레이션으로 비교분석하는 모델과 기초적인 분석결과를 제시한다.

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