• Title/Summary/Keyword: 피로 강도

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Evaluation of Van Khan Tooril's castle, an archaeological site in Mongolia, by Ground Penetrating Radar (GPR을 이용한 몽고 유적지 반 칸 투리일의 성 (Van Khan Tooril's castle)의 평가)

  • Khuut, Tseedulam;Sato, Motoyuki
    • Geophysics and Geophysical Exploration
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    • v.12 no.1
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    • pp.69-76
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    • 2009
  • We report an implementation of the Ground Penetrating Radar (GPR) survey at a site that corresponds to a ruined castle. The objective of the survey was to characterise buried archaeological structures such as walls and tiles in Van Khan Tooril's Ruin, Mongolia, by 2D and 3D GPR techniques. GPR datasets were acquired in an area 10mby 9 m, with 10 cm line spacing. Two datasets were collected, using GPR with 500MHz and 800MHz frequency antennas. In this paper, we report the use of instantaneous parameters to detect archaeological targets such as tile, brick, and masonry by polarimetric GPR. Radar polarimetry is an advanced technology for extraction of target scattering characteristics. It gives us much more information about the size, shape, orientation, and surface condition of radar targets. We focused our interpretation on the strongest reflections. The image is enhanced by the use of instantaneous parameters. Judging by the shape and the width of the reflections, it is clear that moderate to high intensity response in instantaneous amplitude corresponds to brick and tiles. The instantaneous phase map gave information about the location of the targets, which appeared as discontinuities in the signal. In order to increase our ability to interpret these archaeological targets, we compared the GPR datasets acquired in two orthogonal survey directions. A good correlation is observed for the alignments of reflections when we compare the two datasets. However, more reflections appear in the north-south survey direction than in the west-east direction. This is due to the electric field orientation, which is in the horizontal plane for north-south survey directions and the horizontally polarised component of the backscattered high energy is recorded.

Influence of Submersion by Heavy Rain on Growth, Yield and Qua1i1y of Peanut Plant Cultivated in Nakdong Riverside (낙동강유역 땅콩재배지 홍수에 의한 침수피해가 땅콩 생육, 수량 및 품질에 미치는 영향)

  • Kim, Chang-Bae;Lee, Suk-Hee;Yoon, Jae-Tak;Kim, Tak
    • Food Science and Preservation
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    • v.6 no.3
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    • pp.292-296
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    • 1999
  • This experiment was carried out to investigate the growth status, grain yield and quality of the peanut submerged by the flood in grain filling time. The growth status and grain yield of peanut plant after flooding became worse as the flooded day increases and there was remarkable difference in quality between the submerged peanut for just one day and the unsubmerged peanut. For the storage period, the acid value of lipid extracted from submerged peanuts was increased, and the content of linoleic acid of that decreased as the day of submergence became longer. The content of N, P2Of and MgO in peanut plant was increased but the content of K$_2$O was decreased as the submergence duration became longer and the content of soil components were remarkably decreased after submergence. Thus the flooding during the grain filling period caused serious reduction in grain yield and quality of peanut, and more serious reduction was occurred due to longer duration of submergence.

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The effects of Bo-joong-ik-gi-tang administration on Metabolic Responses ; changes in the energy and electrolyte metabolism among long distance runners (보중익기탕(補中益氣湯) 투여가 장거리 달리기 선수의 에너지 및 전해질 대사에 미치는 영향)

  • Song, Sun-Gi;Keum, Dong-Ho;Oh, Jae-Geun;Lee, Myeong-Jong
    • The Journal of Dong Guk Oriental Medicine
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    • v.7 no.1
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    • pp.99-117
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    • 1998
  • Objective This experimental study was designed to investigate effects of Bo-joong-ik-gi-tang administration among long distance runners on changes of the energy and electrolyte metabolism. Materials and Methods All subjects were divided randomly with two groups, Bo-joong-ik-gi-tang Group (N=4) and control group (N=4) and performed to run the 400m track with 70% of HR max about 1 hour. The blood samples were collected from antecubital vein by 5ml syringes at before exercise, immediately after exercise, recovering-10 min. recovering-30 min, recovering-1 hour. These samples were used to analyze for the factors of the change on metabolic responses. First, the primary factors on the changes of the energy metabolism were checked ; Glucose, Free fatty acid, Lactate, LDH. Second, the primary factors on the changes of the electrolyte metabolism were checked ; Na+, CI-. K+. Results 1. The change of the energy metabolism 1) Glucose response was not shown significant difference between two groups. 2) Free fatty acid response in Bo-joong-ik-gi -tang group was significantly increased at recover-10 min. 3) Lactate response in Bo-joong-ik-gi-tang group was significantly decreased at immediately after exercise, recover-10 min, recover-30 min. 4) LDH response was not shown significant difference between two groups. 2. The change of the electrolyte metabolism 1) Na+ response in Bo-joong-ik-gi-tang group was shown significant difference between two groups at before exercise. 2) Cl- response in Bo-joong-ik-gi-tang group was significantly increased at before exercise, immediately after exercise. 3) K+ response in Bo-joong-ik-gi-tang group was significantly increased at recover-10 min. Conclusion According to the above results, it was shown that Bo-joong-ik-gi-tang had the positive effects on changes of the energy and electrolyte metabolism for the long distance runners.

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Crystal Structure Control of Deposit Films Formed by Electrodeposition Process with Dissolved Gases in Seawater and Their Properties (해수 중 용해시킨 기체에 의해 제작한 전착 막의 결정구조 제어 및 특성 평가)

  • Park, Jun-Mu;Choe, In-Hye;Hwang, Seong-Hwa;Gang, Jun;Lee, Chan-Sik;Lee, Myeong-Hun
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2016.11a
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    • pp.164-164
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    • 2016
  • 항만 및 해양 구조물은 육상과는 비교할 수 없을 정도로 가혹한 해수 환경에서 사용되며 계속적으로 부식 손상을 받는다. 따라서 강구조물이 장기적으로 안전하게 사용되기 위해서는 적절한 방식은 물론 철저한 유지관리가 필수적이다. 한편, 현재 해양환경 중 항만, 조선, 해양산업 등에 많이 이용되는 강구조물은 이에 대응하기 위하여 일반적으로 도장방식이나 음극방식이 사용되고 있다. 음극방식은 피방식체를 일정전위로 음극 분극하는 원리로써 외부전원을 인가하거나 비전위의 금속을 희생양극으로 연결하여 방식하는 방법이다. 이와같이 해수 중 음극방식을 실시할 경우 해수 중 용존하는 많은 이온들 중에서 특히 $Ca^{2+}$ 이나 $Mg^{2+}$ 이온이 탄산칼슘, 수산화마그네슘을 주성분으로하는 화합물로 형성된다. 이렇게 생성된 전착막은 산소 확산을 방지하는 물리적 장벽을 형성하고 부식율을 감소시키는 것으로 보고되고 있다. 그러나 전착막은 소지 금속과의 결합력이 불균일 함은 물론 막을 형성하는데 있어서 장시간이 소요된다는 단점이 있다. 따라서 본 연구에서는 해수 중 음극방식 응용 원리에 의해 전착막을 형성하고, 석출속도, 밀착성 및 내식특성을 향상시키기 위해 해수 중 기체를 용해시켜 제작한 막의 특성을 분석-평가하였다. 본 연구에 사용된 기판(substrate)은 일반구조용 강(SS400)을 사용하였으며, 면적은 $70mm{\times}30mm$, 두께는 1 mm로 제작하여 실험을 진행하였다. 외부전원은 정류기(Rectifier, xantrex, XDL 35-5T)를 사용하여 3 및 $5A/m^2$ 의 조건으로 인가하였고, 양극은 Carbon Rod를 사용하였다. 이때 해수에 주입한 이산화탄소의 양은 0.5 NL/min 였다. 각 조건별로 제작된 전착막에 대해 외관관찰, 석출량, 모폴로지, 조성원소 및 결정구조 분석을 실시하였고, 밀착성 및 내식특성을 평가하기 위해 테이핑 테스트(Taping Test, JIS K 5600-5-6)와 3.5 % NaCl 용액에서 전기화학적 양극 분극 시험을 진행하였다. 시간에 따른 전착막의 외관관찰 결과 전류밀도의 증가와 함께 상대적으로 많은 피막이 형성되었고, 용해시킨 기체에 의해 더 치밀하고 두터운 피막이 형성됨을 확인할 수 있었다. 성분 및 결정구조 분석 결과 $Mg(OH)_2$ 성분의 Brucite 및 $CaCO_3$ 성분의 Calcite 구조 및 Aragonite 구조를 확인하였으며, 용해시킨 기체의 영향으로 $CaCO_3$ 성분의 Aragonite 구조가 상대적으로 많이 검출되었다. 이는 해수 중 용해된 이산화탄소의 영향으로 인해 풍부한 ${CO_3}^{2-}$ 이온이 형성되고 용액 pH를 낮게 유지시켜 Ca 화합물 형성이 용이한 환경이 조성되는 것으로 판단된다. 밀착성 및 내식성 평가를 실시한 결과 해수중 용해시킨 기체에 의해 제작한 시편의 경우 견고하고 화학적 친화력이 높은 Aragonite 결정이 표면을 치밀하게 덮어 전해질로부터 산소와 물의 침입을 차단하는 역할을 하여 기체를 용해시키지 않은 $3A/m^2$$5A/m^2$ 보다 비교적 우수한 밀착성 및 내식 특성을 보이는 것으로 사료된다.

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A Fundamental Study on the Fatigue Behavior in the Joints of Steel Members (강부재(鋼部材) 이음부(部)의 피로거동(疲勞擧動)에 관(關)한 기초적(基礎的) 연구(硏究))

  • Lee, Yong Jae;Chung, Yeong Wha
    • Journal of Industrial Technology
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    • v.9
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    • pp.21-28
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    • 1989
  • For the study of the fatigue behavior, high-strength bolted connections on a small scale were manufactured, and carried on fatigue tests. Its experimental values were analysed by stress-fatigue life (S-N) curve. Three types of specimens : the base metal, the cireular hole and the welded sperimens had same net section were made. Through the same tests those experimental values were compared with those of the high-strength bolted conneetions. The results of these studies are as followings. It was found that the fatigue strength in $F_{n=100,000}$ and $F_{n=2,000,000}$ of the high-strength bolted conneetions were much more about 14% and 16% than that of the base metal specimen. It was thought that this trend was due to frictional force increasing fatigue strength. It was known that fatigue strength in $F_{n=100,000}$ and $F_{n=2,000,000}$ of the welded joints were less 29% and 21% than that of base metal specimen. It was thought that that trend was due to weld flaw. It was appeared that the fatigue strength in $F_{n=100,000}$ and $F_{n=2,000,000}$ of the high-strength bolted connections were much more about 38% and 30% than that of welded joint. It was thought that it was due to both frictional force increasing the fatigue strength in bolted connections and weld flaw decreasing the fatigue strength in welded connections. It was found that the fatigue strength in $F_{n=100,000}$ and $F_{n=2,000,000}$ of the B3 specimens were much more 2% and -2% than that of the B4 specimen. It was thought that that trend was due to the frictional force, which concerned with shape of specimen. It was known that the fatigue strength in $F_{n=100,000}$ and $F_{n=2,000,000}$ of the specimen with circular hole was less 61% and 65% than that of base metal. It was known that the allowable stress for bolted joint was higher than that of welded Joints. If that research is continued and more data are accumulated it can be expected that a basic pattern to provided the indicator of the fatigue design of the bolted connections of steel structures and persume the safety and lifeproof of existing structures is given.

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LPI-based Assessment of Liquefaction Potential on the West Coastal Region of Korea (액상화 가능 지수를 이용한 국내 서해안 지역의 액상화 평가)

  • Seo, Min-Woo;Sun, Chang-Guk;Oh, Myoung-Hak
    • Journal of the Earthquake Engineering Society of Korea
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    • v.13 no.4
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    • pp.1-13
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    • 2009
  • Liquefaction is a significant threat to structures on loose saturated sandy soil deposits in the event of an earthquake, and can often cause catastrophic damage, economic loss, and loss of life. Nevertheless, the Korean peninsula has for a long time been recognized as a safe region with respect to the hazard of liquefaction, as the peninsula is located in a moderate seismicity region, and there have been no reports of liquefaction, with the exception of references in some historical documents. However, some earthquakes that have recently occurred in different parts of the world have led to liquefaction in non-plastic silty soils, a soil type that can be found in many of the western coastal areas of Korea. In this study, we first present procedures for evaluating the liquefaction potential, and calculate the liquefaction potential index (LPI) distribution at two western coastal sites using both piezocone penetration test (CPTu) data and standard penetration test (SPT) data. The LPI is computed by integrating liquefaction potential over a depth of 20m, and provides an estimate of liquefaction-related surface damage. In addition, we compared the LPI values obtained from CPTu and SPT, respectively. Our research found that the CRR values from CPTu were lower than those from the SPT, particularly in the range between 40 and 120 for the corrected tip resistance, (qc1N)CS, from the CPTu, or in the range of CRR less than 0.23, resulting in relatively high LPI values. Moreover, it was observed that the differences in the CRR between the two methods were relatively higher for soils with high fine contents.

The Ride Attraction Design of Theme Park (테마파크의 라이드 어트랙션 디자인)

  • 이호숭
    • Archives of design research
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    • v.15 no.3
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    • pp.5-14
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    • 2002
  • The amusement design of a large amusement park, including theme park, largely consists of attraction design, the main facilities, and auxiliary facilities design. The purpose of this study was to discuss the physical motion characteristics of major ride, a recently highlighted representative ride attraction, modern people's thirst for stronger stimuli, and some of the right future directions for amusement design. In theme park, there is an growing trend for rides, especially major rides, to be more thrilling, and Newton's Law motion is basically applied. The rides we can often see provides a thrilling experience that is different from that offered by vehicles we use everyday, due to a variety of speed change, namely of acceleration. Every entertainment facilities, including ride attractions, are externally cutting edge with the use of new technology. but internally, poor theme or concept not only makes it difficult to function properly as attraction but poses a severe threat to theme park survival itself. Theme park will be able to exist as a comprehensive entertainment entity, when attractions are designed to have a perfect harmony among story, method and environment with cultural universality.

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Antioxidaitve and Antibacterial Activities of Endemic Plants Extracts in Korea (국내 자생 식물 추출물의 항산화 활성 및 항균효과)

  • Han, Seung-Ho;Woo, Na-Ri-Yah;Lee, Song-Deuk;Kang, Myung-Hwa
    • Korean Journal of Medicinal Crop Science
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    • v.14 no.1
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    • pp.49-55
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    • 2006
  • Antioxidative and antibacterial activities of endemic plants extracts in Korea were investigated. Hydrogen radical scavenging activity was 99.72% in an elm tree, 99.725 in a Job's tears, 99.575 in an eggplant, and 94.025 in a barrenwort. Antibacterial activity of ethanol extract from 23 different species of wild plants were determined. The gull nut was showed the strongest antibacterial activities (16.0-19.0 mm) and also showed high antibacterial activities in a pine neddles, a gulmyungja, a wild ginger plants, a ginko (9.5-11.5 mm). Only extracts of Saurrranceae extract showed the antibacterial activity in Bacillus subtilus, Stapylococcus aureus, Escherichia coli, Samonella entetotidis. An antibacterial activities were showed weakly in an esungcho and an eggplant. A ground ivy showed Antibacterial activity on Stapylococcus aureus. A barren wort showed in antibacterial activity on Stapylococcus aureus, and E. coli. This results were suggested that many edemic plants resources contains antioxidative and antibacterial substances.

Fabrication of a palladium alloy composite membrane by vacuum electrodeposition (Vacuum electrodeposition에 의한 팔라듐 합금 금속막 제조 및 수소 분리에 관한 연구)

  • 남승은;이규호
    • Proceedings of the Membrane Society of Korea Conference
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    • 1998.10a
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    • pp.96-98
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    • 1998
  • 1. 서론 : 팔라듐이나 이의 합금막들은 높은 선택적 투과특성으로 인해 수소 정제나 분리막 반응기와 같은 산업응용 분야에서 매우 높은 관심을 갖고 있다. 상업적으로 이용되고 있는 이러한 막들은 통상적인 metallugical process에 의해 제조괸 self-supported type으로 수소 투과 속도가 낮을 뿐만 아니라 팔라듐 등은 고가의 귀금속이므로 비경제적이다. 따라서 현재 대부분의 연구자들은 기계적 강도를 유지하기 의한 다공성 지지체 위에 얇은 금속 박막을 코팅함으로서 투과성을 높이는 동시에 경제적인 복합막 형태의 막을 만드는데 연구의 촛점을 맞추고 있다. 이러한 형태의 막을 제조하기 위한 금속 박막 제조법은 무전해 도금법(electroless deposition), 화학증착법(CVD), 스퍼터링(sputtering), 전해도금법(electrodeposition) 등이 시도되었다. 그러나 수소에 대한 우수한 선택적 투과 특성을 갖기 의해서는 대부분 5$\mu$m 이상의 두꺼운 막을 제조하였으며 이보다 얇은 막의 제조에 한계가 있기 때문에 이들 막에 대한 기체 투과 특성에 대한 연구결과는 많지 않다. 본 연구에서는 기존의 전기도금법을 응용한 소위 'vacuum electrodeposition' 이란 새로운 기술을 도입함으로써 우수한 선택적 투과성을 갖는 2$\mu$m 이하의 팔라듐 합금 박막 제조를 가능하게 하였다. 지지체 표면의 거칠음 정도, 평균 기공 크기 등의 지지체 성질의 조절에 의한 금속 박막의 핀홀을 최소화함으로써 질소와 같은 inert gas의 투과도는 거의 없게 유지하는 동시에 금속 박막 두께, 결정 구조(e.g. grain size), 합금 조성 등을 조절함으로써 수소의 투과도를 높이고자 하였다. 있다. 후자의 경우, 미량의 과산화수소수 (1~10,000 ppm)를 이용해 처리 해주는 방법의 경우 경제적으로 큰 장점이 있고, 처리가 단순하다는 장점이 있으나 과산화수소수 자체에 포함하고 있는 높은 impurit level, 그리고 처리후 장시간의 flushing time을 가져야 한다는 단점등이 존재 하고 있다.요구된다. 몰입이 가능하여 임계치가 저하된 것으로 여겨진다. 또한 광학적 이득의 존재는 이 구조에 의한 극단파장 반도체 레이저다이오드의 실현 가능성을 나타내는 것이다.548 mL에 비해 통계학적으로 의의 있게 적었다(p<0.05). 결론: 관상동맥우회로 조성수술에서 전방온혈심정지액을 사용할 때 희석되지 많은 고농도 포타슘은 fliud overload와 수혈을 피하고 delivery kit를 사용하지 않음으로써 효과적이고 만족할 만한 심근보호 효과를 보였다.를 보였다.4주까지에서는 비교적 폐포는 정상적 구조를 유지하면서 부분적으로 소폐동맥 중막의 비후와 간질에 호산구 침윤의 소견이 특징적으로 관찰되었다. 결론: 분리 폐 관류는 정맥주입 방법에 비해 고농도의 cisplatin 투여로 인한 다른 장기에서의 농도 증가 없이 폐 조직에 약 50배 정도의 고농도 cisplatin을 투여할 수 있었으며, 또한 분리 폐 관류 시 cisplatin에 의한 직접적 폐 독성은 발견되지 않았다이 낮았으나 통계학적 의의는 없었다[10.0%(4/40) : 8.2%(20/244), p>0.05]. 결론: 비디오흉강경술에서 재발을 낮추기 위해 수술시 폐야 전체를 관찰하여 존재하는 폐기포를 놓치지 않는 것이 중요하며, 폐기포를 확인하지 못한 경우와 이차성 자연기흉에 대해서는 흉막유착술에 더 세심한 주의가 필요하다는 것을 확인하였다. 비디오흉강경수술

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Guidelines for Free-Hand Aspiration(FHA) of Putaminal Hemorrhage (피각부 자발성 뇌내출혈의 혈종흡입술을 위한 지표)

  • Yim, Sin Gil;Oh, Min Suk;Lim, Jun Seob;Kang, Myung Gi;Kwak, Yeon Sang;Park, Seung Gyu;Song, Gyung Bae;Kim, Han Yung
    • Journal of Korean Neurosurgical Society
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    • v.30 no.sup2
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    • pp.294-299
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    • 2001
  • Objectives : CT-guided stereotactic evacuation for spontaneous intracerebral hemorrhage can minimize the brain damage and can be performed safely and simply under local anesthesia. But that procedure is time consuming and has a risk of rebleeding because of the stress during head pin fixation. So authors describe easy and precise guidelines for FHA of putaminal hemorrhage without stereotactic instrument. Methods and Materials : We analyzed the data of 298 patients who underwent CT-guided stereotactic aspiration of putaminal hematoma in our hospital between January 1990 and December 2000. We divided the patients into three groups according to the location of hematoma : anterior portion, middle portion and posterior portion of putamen. Total number of catheters inserted into the hematoma were 345 and there were with regard to the direction and depth of catheters. Results : Proposed guidelines of catheter insertion to putaminal hemorrhage in our institution. 1) hematoma at the anterior portion of putamen ; Direction of catheter was the midpupillary line of the eye and the point intersecting a line drawn from the burr hole to a point between external auditory meatus(EOM) and 1cm posterior to EOM. Depth of catheter was 6-6.5cm. 2) hematoma at the middle portion of putamen ; Direction of catheter was the midpupillary line of the the eye and the point intersecting a line drawn from the burr hole to a point between 1cm and 2cm posterior to EOM. Depth of catheter was 6.5-7cm. 3) hematoma at the posterior portion of putamen ; Direction of catheter was 15 degree laterally from the midpupillary line of the eye and the point intersecting a line drawn from the burr hole to a point between 2cm and 3cm posterior to EOM. Depth of catheter was 7-7.5cm. We have performed FHA of putaminal hemorrhage in 48 cases according to this guideline. All catheter were inserted exactly at the center of hematoma and average operation time was about 30 minutes. Conclusion : Our proposed guidelines for putaminal hemorrhage are considered to be safe and simple method with similar accuracy and rapid decompression compared with traditional stereotactic method. Main advantages of this technique were unnecessity of stereotactic frame application and less time requirement for hematoma removal.

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