• 제목/요약/키워드: Case Depth

검색결과 2,908건 처리시간 0.032초

방사선 치료용 고에너지 전자선의 조직 내 선량분포 특성에 관한 연구 (Study on Characteristics of Dose Distribution in Tissue of High Energy Electron Beam for Radiation Therapy)

  • 나수경
    • 대한방사선치료학회지
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    • 제14권1호
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    • pp.175-186
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    • 2002
  • The purpose of this study is directly measure and evaluate about absorbed dose change according to nominal energy and electron cone or medical accelerator on isodose curve, percentage depth dose, contaminated X-ray, inhomogeneous tissue, oblique surface and irradiation on intracavitary that electron beam with high energy distributed in tissue, and it settled standard data of hish energy electron beam treatment, and offer to exactly data for new dote distribution modeling study based on experimental resuls and theory. Electron beam with hish energy of $6{\sim}20$ MeV is used that generated from medical linear accelerator (Clinac 2100C/D, Varian) for the experiment, andwater phantom and Farmer chamber md Markus chamber und for absorbe d dose measurement of electron beam, and standard absorbed dose is calculated by standard measurements of International Atomic Energy Agency(IAEA) TRS 277. Dose analyzer (700i dose distribution analyzer, Wellhofer), film (X-OmatV, Kodak), external cone, intracavitary cone, cork, animal compact bone and air were used for don distribution measurement. As the results of absorbed dose ratio increased while irradiation field was increased, it appeared maximum at some irradiation field size and decreased though irradiation field size was more increased, and it decreased greatly while energy of electron beam was increased, and scattered dose on wall of electron cone was the cause. In percentage depth dose curve of electron beam, Effective depth dose(R80) for nominal energy of 6, 9, 12, 16 and 20 MeV are 1.85, 2.93, 4.07, 5.37 and 6.53 cm respectively, which seems to be one third of electron beam energy (MeV). Contaminated X-ray was generated from interaction between electron beam with high energy and material, and it was about $0.3{\sim}2.3\%$ of maximum dose and increased with increasing energy. Change of depth dose ratio of electron beam was compared with theory by Monte Carlo simulation, and calculation and measured value by Pencil beam model reciprocally, and percentage depth dose and measured value by Pencil beam were agreed almost, however, there were a little lack on build up area and error increased in pendulum and multi treatment since there was no contaminated X-ray part. Percentage depth dose calculated by Monte Carlo simulation appeared to be less from all part except maximum dose area from the curve. The change of percentage depth dose by inhomogeneous tissue, maximum range after penetration the 1 cm bone was moved 1 cm toward to surface then polystyrene phantom. In case of 1 cm and 2 cm cork, it was moved 0.5 cm and 1 cm toward to depth, respectively. In case of air, practical range was extended toward depth without energy loss. Irradiation on intracavitary is using straight and beveled type cones of 2.5, 3.0, 3.5 $cm{\phi}$, and maximum and effective $80\%$ dose depth increases while electron beam energy and size of electron cone increase. In case of contaminated X-ray, as the energy increase, straight type cones were more highly appeared then beveled type. The output factor of intracavitary small field electron cone was $15{\sim}86\%$ of standard external electron cone($15{\times}15cm^2$) and straight type was slightly higher then beveled type.

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MRI를 통한 풍부혈(GV16)의 안전 자침 깊이에 대한 연구 (Safe Needling Depth of Pungbu(GV16) with MRI-a Retrospective Study)

  • 양현정;박해인;이광호
    • Journal of Acupuncture Research
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    • 제32권4호
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    • pp.11-16
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    • 2015
  • Objectives : The purpose of this study is to determine the safe needling depth of Pungbu($GV_{16}$) retrospectively by using magnetic resonance imaging (MRI). Methods : We chose 114 Brain or C-spine MRI images from the Sang-Ji hospital picture archiving communication system. We measured the shortest distance from skin to cerebral dura mater passing by posterior edge of the foramen magnum on the sagittal view for the depth of Pungbu. We analyzed the differences between male and female measured values by using a student t-test. Results : The average depth of male insertion was $49.71{\pm}6.32mm$ and the shortest depth of insertion was 36.29 mm. The average depth of female insertion was $39.84{\pm}5.25mm$ and the shortest depth of insertion was 30.02 mm. The results showed a significant difference according to gender (p=0.00). Conclusions : The depth of male insertion is deeper than that of female, and the safe needling depth in the case of males is 36.29-67.35 mm, while the safe needling depth in the of females is 30.02-52.18 mm.

능동 소나 체계에서의 표적 탐지거리 예측 알고리즘과 최적 탐지깊이 결정에의 응용 (Detection Range Estimation Algorithm for Active SONAR System and Application to the Determination of Optimal Search Depth)

  • 박재은;김재수
    • 한국해양공학회지
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    • 제8권1호
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    • pp.62-70
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    • 1994
  • In order to estimate the detection range of a active SONAR system, the SONAR equation is commonly used. In this paper, an algorithm to calculate detection range in active SONAR system as function of SONAR depth and target depth is presented. For given SONAR parameters and environment, the transmission loss and background level are found, signal excess is computed. Using log-normal distribution, signal excess is converted to detection probability at each range. Then, the detection range is obtained by integrating the detection probability as function of range for each depth. The proposed algorithm have been applied to the case of omni-directional source with center frequency 30Hz for summer and winter sound profiles. It is found that the optimal search depth is the source depth since the detection range increase at source depth where the signal excess is maximized.

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방사선투과사진에 의한 결함깊이 및 높이의 평가 (Estimation of Flaw Depth and Height by Radiography)

  • 강계명;박은수;심언덕
    • 한국재료학회지
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    • 제12권8호
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    • pp.682-687
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    • 2002
  • The three-dimensional estimation on the depth and height of flaw by using the difference of radiographic contrast density was studied. First, the specimens having artificial flaws of various depths and heights were prepared and the radiographic testing was performed. The radiographic depth of flaw was investigated and estimated on the effect of the scattered radiation with the change of distance between flaw and film. The height of flaw was estimated from the radiographic test with the reference specimen. The radiographic contrast with flaw depth decreased with increasing the flaw depth. The scattered radiation increased with increasing flaw depth and varied with the location between flaw and film. However, in the case of flaw height, the contrast density increased with increasing flaw height. It is thought due to the change in volume generating the scattered radiation which reaches a film.

복강내침술과 관련 혈위의 자침 깊이에 대한 고찰 (Review on Intraperitoneal Acupuncture and Needling Depth)

  • 김소연
    • Korean Journal of Acupuncture
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    • 제40권3호
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    • pp.55-61
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    • 2023
  • Objectives : To review the needling depth, therapeutic and adverse effects of intraperitoneal acupuncture and related acupoints. Methods : Studies and reports from the literature, Korean medical health insurance data and databases were searched and selected. Results : The depth of needle insertion for acupoints related to intraperitoneal acupuncture has been documented to range from 0.9 to 10.5 cm depending on the acupoints and literature. In studies of safe needling depth, the justice of safe needling depth varied from study to study, but was generally based on the peritoneum, and the depth varies by patient age, sex, body type, and weight. Clinical studies in China have shown good efficacy and no side effects of abdominal long needle acupuncture, but there have been case reports of adverse events following abdominal acupuncture. Conclusions : To ensure both therapeutic effectiveness and safety of intraperitoneal acupuncture, It is necessary to utilize the ultrasound in clinical practice and conduct related research.

MRI를 통한 황문혈(BL51)과 지실혈(BL52)의 자침 깊이에 대한 연구 (A Retrospective Study on Needling Depth of Hwangmun (BL51) and Jisil (BL52) with MRI)

  • 양현정;심호연;이광호
    • Journal of Acupuncture Research
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    • 제33권2호
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    • pp.89-96
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    • 2016
  • Objectives : The aim of this study is to investigate the needling depth of Hwangmun (BL51) and Jisil (BL52) retrospectively using an L-spine MRI. Methods : We measured the shortest distance from the skin to transversalis fascia at both sides of Hwangmun and Jisil, and analyzed the difference between male and female using a student t-test, and between the left and right sides with a paired t-test. Results : In the case of males, the average depth of left Hwangmun was $48.24{\pm}10.16mm$, and that of right was $47.23{\pm}9.59mm$ ; left Jisil was $56.91{\pm}9.00mm$ and right was $55.74{\pm}8.75mm$. In the case of females, the average depth of left Hwangmun was $42.26{\pm}9.29mm$, and that of right was $41.63{\pm}9.32mm$ ; left Jisil was $49.21{\pm}10.77mm$ and right was $48.41{\pm}11.38mm$. The depth of male insertion was deeper than that of female in Jisil, but there was no significant difference according to gender in Hwangmun. Conclusion : For males, the needling depth of left Hwangmun is 37.21 ~ 68.23 mm and right is 36.91 ~ 70.50 mm, while left Jisil is 42.97 ~ 70.84 mm and right is 43.75 ~ 72.00 mm. For females, the needling depth of left Hwangmun is 26.80 ~ 68.28 mm and right is 25.70 ~ 65.59 mm, while left Jisil is 30.94 ~ 79.06 mm and right is 28.13 ~ 77.27 mm.

2차원 및 3차원 해석에 의한 토류벽의 변위에 관한 비교 연구 (A Relative Study on the Displacement of Earth Retaining Wall by 2 and 3 Dimentional Analysis)

  • 박춘식;박해찬;김종환;박영준
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2010년도 춘계 학술발표회
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    • pp.801-810
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    • 2010
  • Until now, design of Earth Retaining is practiced by 2nd dimensional analysis for convenience of analysis and time saving. However, the construction field is 3rd dimension, in this study, practised the 3rd dimensional analysis which can reflect the field condition more exactly the scope of earth retaining wall, and researched about the effective and economical way of design, compared and reviewed with the results, by practising both the 2nd and 3rd dimensional analysis. existing 2nd dimension. the depth of excavation, depth of embedded and soil condition. As result, under the whole conditions, more displacement came to appear to the value as result of 3rd dimensional analysis more than the result of 2nd dimensional analysis. Accordingly, the displacement by the 2nd dimension analysis is underestimated. Moreover, results of 2nd and 3rd dimensional analysis, there is no difference at displacement, when the depth of embedded is 0.5H, 1.0H and 1.5H, but Displacement of 1.5H is smaller than 0.5H, 1.0H. That is, the bigger the depth of embedded becomes, the displacement of Earth Retaining Wall appeared smaller. The displacement of earth retaining wall according to depth of excavation appeared bigger, when the depth of excavation is increased. In the meantime, when the soil condition is different, in the 2nd dimensional analysis, the displacement appeared biggest, in case of the clay layer, but in the 3rd dimensional analysis, in the beginning of excavating, the displacement of earth retaining wall appeared bigger in case of clay layer, but as excavating is in progress, the displacement of both compound soil layer and sand layer appeared big.

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이앙시기 및 담수심 변화에 따른 논벼 수요량 변화 분석 (Analysis of Variance of Paddy Water Demand Depending on Rice Transplanting Period and Ponding Depth)

  • 조건호;최경숙
    • 한국농공학회논문집
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    • 제63권3호
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    • pp.75-85
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    • 2021
  • This study evaluated variations in the paddy rice water demand based on the continuous changing in rice transplanting period and ponding depth at the four study paddy fields, which represent typical rice producing regions in Korea. Total 7 scenarios on rice transplanting periods were applied while minimum ponding depth of 0 and 20 mm were applied in accordance with maximum ponding depth ranging from 40 mm to 100 mm with 20 mm interval. The weather data from 2013 to 2019 was also considered. The results indicated that the highest rice water demand occurred at high temperature and low rainfall region. Increased rice transplanting periods showed higher rice water demand. The rice water demand for 51 transplanting days closely matched with the actual irrigation water supply. In case of ponding depth, the results showed that the minimum ponding depth had a proportional relationship with rice water demand, while maximum ponding depth showed the contrary results. Minimum ponding depth had a greater impact on rice water demand than the maximum ponding depth. Therefore, these results suggest that increasing the rice transplanting period, which reflects the current practice is desirable for a reliable estimation of rice water demand.

중층 트롤 시스템의 계측 및 운동 특성 (Measurements of Midwater Trawl System and Dynamic Characteristics)

  • 이춘우
    • 수산해양기술연구
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    • 제34권3호
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    • pp.294-301
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    • 1998
  • Towing performance of a midwater trawl system was examined aboard the training ship KAYA(2900ps) at the East Sea using the midwater trawl gear that had been designed and manufactured in accordance with the vessel. In this experiment, the trawl system data, the towing speed, the length and tension of the warp, net mouth height, and the depth of otter boards and net were measured and analyzed. The results are as follows: 1. In case of heaving in the warp with constant towing speed, the tension was suddenly increased and then again was reduced and after returned to the original steady state tension. At this time, net height was reduced a bit by ascension of ground rope, but returned to it’s original value. In the case where the warp was paid out, the tension was suddenly decreased and after increased and then returned to the tension of the original state, and the net height was greatly increased instantly by the sinking of the ground rope and then returned to the steady state 2. In the case of increased towing speed mm constant warp length, the tension was increased, and reducing the net height, the gear depth was decreased. On the other hand, in the case where towing speed was reduced, the tension was reduced and the gear depth and net height was increased. 3. Otter boards show a swing motion in the scope of 5~ 10m continuously. Otter boards responded to the state change of the trawl system at first, and then the motion of the net appeared. 4. The depth of net center was about 20m deeper than that of the otter boards, it shows about 0.4 times the warp length at the 4knots towing speed.

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플라즈마 침탄 공정을 이용한 SCM415강의 표면 경화 특성 (Characteristics of Plasma Carburizing Process in Surface Hardening of SCM415 Steel)

  • 김대욱;김동원;임병수;김석범
    • 한국재료학회지
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    • 제8권8호
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    • pp.707-713
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    • 1998
  • 현재 자동차용 소재 및 기계부품에 폭넓게 이용되는 SCM415강의 플라즈마 침탄 특성을 연구하기 위해 가스조성, 압력, 전류밀도, 온도 및 시간을 변수로 사용하였다. 가스조성의 경우 저합금강에서는 수소 가스 효과보다 메탄가스에 의해 주로 침탄특성이 좌우되며 메탄가스 100%일 때 시편 내의 모든 방향에서 경화층 분포가 일정하고, 최대의 유효경화깊이를 얻을 수 있었다. 가스압력이나 플라즈마 전압이 상승할 때 전류밀도가 상승하게 되는데, 이에 따라 최표면의 탄소농도가 증가되어 강의 유효경화깊이는 증대되었다. 침탄 온도일 경우 적어도 85$0^{\circ}C$이상되어야 유효경화깊이를 얻을 수 있었고, 온도가 상승할수록 유효경화깊이의 증가를 나타내어 침탄 효과가 우수하였다. 탄소의 확산 깊이는 침탄 시간의 제곱근에 비례하는 것으로 나타났다. 플라즈마 치탄한 강의 피로강도를 평가한 결과 열처리하지 않은 시편이나 재가열처리한 시편에 비해 높은 피로강도를 나타내었다.

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