• Title/Summary/Keyword: Groove Width

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Scanning Electron Microscopic Studies on the Features of Compression Wood, Opposite Wood, and Side Wood in Branch of Pitch Pine(Pinus rigida Miller) (리기다소나무 (Pinus rigida Miller) 지재(枝材)의 압축이상재(壓縮異常材), 대응재(對應材) 및 측면재(側面材) 특성(特性)에 관한 주사전자현미경적(走査電子顯微鏡的)인 연구(硏究))

  • Eom, Young-Geun;Lee, Phil-Woo
    • Journal of the Korean Wood Science and Technology
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    • v.13 no.1
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    • pp.3-18
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    • 1985
  • In Korea, a study on the anatomical features of pitch pine (pinus rigida Miller) branch wood through photo-microscopical method was reported in 1972 by Lee. Therefore, as a further study of Lee's on the anatomical features in branch wood of pinus rigida miller that grows in Korea, compression wood, opposite wood, and side wood were selected and treated for the purpose of comparing their structures revealed on cross and radial surface through scanning electron microscope in this study. The obtained results in this study were summarized as follows; 1. The trachied transition from earlywood to late wood is very gradual and the tracheids are nearly regular in both arrangement and size in compression wood but this transition in opposite wood and side wood is abrupt and the tracheids in opposite wood and side wood are less regular than those in compression wood. Also, the annual ring width of opposite wood is narrower than that of compression wood or side wood and the rays revealed on cross surface of side wood are more distinct than compression wood and opposite wood rays. 2. The tracheids of compression wood show roundish trends especially in earlywood but those of opposite wood and side wood show some angular trends. And intercellular space, helical cavity, and spiral check are present in both earlywood and latewood of compression wood but not present in opposite wood and side wood irrespective of earlywood and latewood. 3. The wall thickness of latewood tracheid is similar to that of earlywood tracheid in compression wood whereas the wall thickness of latewood tracheid is by far thicker than that of earlywood tracheid in opposite wood and side wood and the S3 layer of secondary wall is lack in compression wood tracheid unlike opposite wood and side wood tracheid. 4. The tracheids in compression wood are often distorted at their tips unlike those in opposite wood and side wood and the bordered pit in compression wood tracheid is located at the bottom of helical groove unlike that in opposite wood and side wood tracheid. 5. The bordered pits in radial wall of opposite wood and side wood tracheids are oval in shape but those of compression wood tracheids show some modified oval shape. 6. In earlywood of side wood, the small apertures of cross-field pits are roundish triangle to rectangle and the large one are fenestriform through the coalition of two small ones. However, the small apertures of cross-field pits are upright oval and the large ones are procumbent oval shape in earlywood of opposite wood and the apertures of cross-field pits in compression wood are tilted bifacial convex lens shape in earlywood and slit in late wood because of the border on tracheid side.

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Simple and Effective Surgical Repair with Vascular Graft Strip for Ischemic MR (인조혈관대를 이용한 허혈성 승모판막 폐쇄부전의 수술적 치료)

  • 민호기;이승훈;이주현;성기익;박계현;전태국;박표원;이영탁
    • Journal of Chest Surgery
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    • v.36 no.9
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    • pp.646-650
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    • 2003
  • Many surgical techniques for ischemic mitral regurgitation (IMR) have been used with their excellent results and advantages. Here, we report our simple posterior annuloplasty techniques using vascular graft strip with their early results. Material and Method: Twenty two patients (13 male) underwent the operations for IMR (excluding the papillary muscle rupture) from December 2001 to January 2003. Preoperative risk factors were low ejection fraction (<35%, n=9), hypertension (n=13), diabetes (n=9), and renal failure (Cr>2.5, n=4). The wide dissection beneath the both vena cavae and interatrial groove after bicaval cannulation enabled the easy exposure of mitral valve even in the small left atrium. After eight or nine interrupted sutures in posterior annulus for anchoring the 6 mm width vascular graft strip, symmetric (n=8) or asymmetric (n=14) annuloplasty were done. Combined surgeries were CABG (n=21), Dor procedures (n=3), tricuspid valve annuloplasty (n=1), Maze operation (n=1), and aorto-right subclavian artery bypass (n=1). Result: Except for one surgical mortality, all the patients were doing well and the mean grade of regurgitation was decreased from 2.95 to 0.88, however the ejection fraction had not changed significantly just before discharge. Post-operative valve function evaluated before discharge revealed no residual regurgitation in 8 (including 1 patient with mild stenosis due to over reduction), minimal in 11, mild in 2, and mild to moderate regurgitation in 1. One patient who had ischemic cardiomyopathy and renal failure died of the arrhythmia during the hemodialysis. Conclusion: These observations suggest that the annuloplasty with vascular graft strip could be a safe and cost effective techniques for ischemic mitral regurgitation. However, the long term evaluation for the mitral valve function should be defined for the final conclusion.

Dose Distribution and Characterization for Radiation Fields of Multileaf Collimateor System (방사선 입체조형치료용 다엽콜리메이터의 특성과 조직내 선량분포 측정)

  • Chu, Sung-Sil;Kim, Gwi-Eon
    • Radiation Oncology Journal
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    • v.14 no.1
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    • pp.77-85
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    • 1996
  • Purpose : Multileaf collimator(MLC) is very suitable tool for conformal radio-therapy and commissioning measurements for a multileaf collimator installed on a dual energy accelerator with 6 and 10MV photons are required, For modeling the collimator with treament planning software, detailed dosimetric characterization of the multileaf collimator including the penumbra width, leaf transmission between leaf leakage and localization of the leaf ends and sides is an essential requirement. materials and Methods : Measurement of characteristic data of the MLC with 26 pair block leaves installed on CLINAC 2100C linear accelerator was performed. Low sensitive radiographic film(X-omatV) was used for the penumbra measurement and separate experiments using radiographic film and thermoluminescent dosimeters were performed to verify the dose distribution, Measured films were analized with a photodensitometer of WP700i scanner. Results : For 6 & 10 MV x-ray energies, approximately $2.0\%$ of photons incident on the multileaf collimator were transmitted and an additional $0.5\%$ leakage occurs between the leaves. Localizing the physical end of the leaves showed less than 1mm deviation from the $50\%$ decrement line and this difference is attributed to the curved shaped end on the leaves One side of a sin히e leaf corresponded to the $50\%$ decrement line, but the opposite face was aligned with a lower value. This difference is due to the tongue and groove used to decrease between leaf leakage. Alignment of the leaves to form a straight edge resulted larger penumbra at far position from isocenter as compare with divergent alloy blocks. When the MLC edge is stepped by sloping field, the isodose lines follow the leaf pattern and Produce scalloping isodose curves in tissue. The effective penumbra by 45 degree stepped MLC is about 10mm at 10cm depth for 6MV x-ray. The difference of effective penumbra in deep tissue between MLC and divergent alloy blocks is small (5mm). Conclusion : Using the characteristic data of MLC, the MLC has the clinlical acceptability and suitability for 3-D conformal radiotherapy except small field size.

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Achievement of Excavation of Gwiam(Turtle Rock) and Nakseojae Restoration in Bogil-do Yun,Seondo Wonlim (보길도 윤선도원림(명승 제34호) 낙서재지역 원형복원과 귀암(龜巖) 발굴의 성과)

  • Lee, Won-Ho
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.30 no.3
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    • pp.111-120
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    • 2012
  • This study regards a series of achievement on Wonlim(Garden) Cultural Properties Excavation Project, led by field of landscape architecture. It will mainly describe excavation results of Gwiam(龜巖: Turtle rock) and historical value of it in terms of Nakseojae(樂書齋) restoration in Bogil-do Yun,Seondo Wonlim(Scenic Sites, No.34). Gwiam(Turtle rock) was found 14.6m apart from the north of Nakseojae, and it covered with 10~15m topsoil tilted toward Nakseojae, The size of Gwiam, which was Granite, was 360cm length, 270cm width, 95cm high. The Edge of Gwiam's North west part was of triangular shape forming Turtle head. The back of the Turtle head was form of Tortoise-shell because of wide backboard with both side groove. The southeast part of Gwiam projected was Turtle's tail. This Granite was obvious Turtle shape artificially made, and there are less likely to relocate from place to place. This Turtle-shaped Gwiam is important landmark for Nakseojae, which is one of the four spiritual creatures written in Bogildoji(甫吉島識) and Gosanyugo(孤山遺稿) by Yunwi. According to Bogildoji, it is estimated that Gwiam were on the axis with Soeunbyung(小隱屛), Nakseojae and was buried when Yiguan(Gosan's grandson) reconstructed a building. Also, it was place for enjoying the moon. But, Even after three times excavation in Nakseojae, there was no way to identify further information regarding Gwiam, so it was a matter of mystification. As a result of this study, Gwiam is laid bare to light in at least 260 years, so it is good example for boosting importance of landscape architecture field and restoring Nakseojae. Furthermore, firm base-soil was discovered in 135m high Rock Mass below, so natural ground of Nakseojae can be estimated by this basis. To be conclusion, Preservation Process for Gwiam and Estimation Space through interpretation of four spiritual creatures(四靈) in Gosan's Poetry should be continue.