• Title/Summary/Keyword: Whole field

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A comparative study of dose distribution for whole brain with field-in-field technique (전뇌(Whole Brain)치료 시 Field-in-Field Technique 적용에 관한 고찰)

  • Kim Bo Kyoum;Lee Je Hee;Jung Chi Hoon;Pack Heung Deuk
    • The Journal of Korean Society for Radiation Therapy
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    • v.17 no.1
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    • pp.9-17
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    • 2005
  • Purpose : Uniform dose distribution of the target volume is very important in the radiation treatment. We will evaluate the usefulness of Field-in-Field Technique use to get uniform dose distribution of the target volume and try to find Apply possibility out to a whole brain treatment patient of various thickness. Material and method : We compare the dose distribution when we applied Field-in-Field Technique and parallel opposed fields technique. establish the treatment plan to a phantom(acryl 16cm spheral phantom) and do the measurement, assessment use the TLD and Low sensitivity film. Also the assessment did Apply possibility of Field-in-Field Technique to 20 patient object of various thickness. Result : In the case to use the parallel opposed fields at the whole brain treatment $10-12\%$ high dose region appeared but reduce to $3-4\%$ lesses when we used the Field-in-Field technique. We could get similar numerical value the film and TLD measurement result also. The change of the dose distribution appeared to its ${\pm}1{\sim}2\%$ although it applied such Field-in-Field technique to various patient so that we were identical. Conclusion : We can get uniform dose distribution of in the treatment region if we apply the Field-in-Field technique at the whole brain treatment. Also alternate can play the role of the wedge filter and 3D compensator and We are thought by minimizing the obstacle to be happened due to the high dose region when radiation treatment.

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Studies on the Domestication of of Field Bean ( Glycine soja Sieb and Zucc ) for Forage Crop I. Esterase isozyme variation and nutritive value of field bean (돌콩 ( Glycine soja Sieb and Zucc ) 의 사료작물화에 관한 연구 I. 돌콩의 Esterase isozyme 변이와 사료적 가치 평가)

  • Lee, Sung K.;Lee, Eun;Choi, Il
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.13 no.2
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    • pp.86-92
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    • 1993
  • The variation of the esterase isozyme, germination rate, chemical composition and digestibility of field bean(G1ycine soja S. and Z.) were estimated. The results are as follows; 1. The banding patterns of the esterase isozyme in field bean were varied with the tissue and habitat. 2. The enzyme activity of the Est-I, Est-2, Est-3 and Est-4 in field bean showed a high value compared with the other enzyme. 3. The range of germination temperature in field bean was 10-40C and the optimum germination temperature was 25- 38^{\circ}C.$. 4. The crude protein(CP) contents was 19.9% in the whole plant, 27.8% in the leaf and 45.9% in the seed, the cellulose contents was 29.5% in the whole plant, 23.0% in the leaf and 13.8% in the seed, the neutral detergent fiber(NDF) was 62.6% in the whole plant, 47.9% in the leaf and 47.9% in the seed and the acid detergent fiber(ADF) was 44.5% in the whole plant, 28.4% in the leaf and 28.4% in the seed, respectively. 5. The digestibility of the field bean was 44.1% in the whole plant, 49.6% in the leaf and 75.1% in the seed, NDF was 26.2% in the whole plant 46.2% in the leaf, ADF was 29.0% in the whole plant, 47.7% in the leaf and 58.0% in the seed and Cellulose was 48.7% in the whole plant, 58.0% in the leaf and 70.2% in the seed, respectively. 6. Total digestible nutrients(TDN) of the field bean was 47.4% in the whole plant, 51.5% in the leaf and 70.2% in the seed, respectively. The digestible energy(DE) value was 2.1 kcal/g in the whole plant, 2.27 kcal/g in the leaf and 3.10 kcal/g in the seed and the metabolizable energy(ME) value was 1.72 kcal/g in the whole plant, 1.86 kcal/g in the leaf and 3.23 kcal/g in the seed, respectively.

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Effects of Whole Body Fatigue and Limited Visual Field on Postural Stability (전신 피로와 시야 제한이 자세균형 능력에 미치는 영향)

  • Park, Sung Ha
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.39 no.3
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    • pp.39-46
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    • 2016
  • Loss of postural stability can possibly lead to slip and fall accidents in the number of workplaces and everyday life. This study was aimed to examine the effects of whole body fatigue and partially limited visual field on the ability of maintaining postural balance during quiet standing. A group of twelve healthy male subjects participated in the experiment. Before and after experiencing the whole body fatigue induced by bicycling exercises, the position coordinates of subject's center of pressure (COP) were obtained under the two levels of visual field condition (i.e., open visual field and limited visual field). Four levels of the whole body fatigue examined were rest, 300watt, 600watt, and 900watt. Position coordinates of COPs measured on a force plate were then converted into the total length of postural sway path in both the medio-lateral (ML) direction and the anterior-posterior (AP) direction. Two-way ANOVA result showed that the length of sway path in the AP direction became significantly larger as the whole body fatigue accumulated. Post-hoc test revealed statistically significant differences between rest and 900watt and between 300watt and 900watt. The significant increase of the sway length was also found when the visual field was partially obstructed by the boxes. In the ML direction, however, there was no statistically significant difference of the postural sway in both the AP and ML directions. The results imply that the ability of maintaining postural stability can be reduced significantly due to such tasks along with whole body fatigue. The postural balance can also be impaired by the limited visual field.

Real-time estimation of Temperature Distribution of a Ball Screw System Using Modal Analysis and Observer (모드해석과 관측기에 의한 볼스크류 온도분포의 실시간 예측)

  • 김태훈
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2000.04a
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    • pp.635-640
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    • 2000
  • Thermal deformation of machine tools can be evaluated from the analysis of the whole temperature field. However, it is extremely inefficient and impossible to acquire the whole temperature field by measuring temperatures of every point. So, a temperature estimator, which can estimate the whole temperature field from the temperatures of just a few points, is required. In this paper, 1-dimensional heat transfer problem is modeled with modal analysis and state space equations. and then state observer is designed to estimate the intensity of heat source and the whole temperature field in real-time. The reliability of this estimator is verified by making a comparison between solutions by the proposed method and the exact solutions of examples. The proposed method is applied to the estimation of temperature distribution in a ball screw system.

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Parotid gland sparing effect by computed tomography-based modified lower field margin in whole brain radiotherapy

  • Cho, Oyeon;Chun, Mison;Park, Sung Ho;Oh, Young-Taek;Kim, Mi-Hwa;Park, Hae-Jin;Nam, Sang Soo;Heo, Jaesung;Noh, O Kyu
    • Radiation Oncology Journal
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    • v.31 no.1
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    • pp.12-17
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    • 2013
  • Purpose: Parotid gland can be considered as a risk organ in whole brain radiotherapy (WBRT). The purpose of this study is to evaluate the parotid gland sparing effect of computed tomography (CT)-based WBRT compared to 2-dimensional plan with conventional field margin. Materials and Methods: From January 2008 to April 2011, 53 patients underwent WBRT using CT-based simulation. Bilateral two-field arrangement was used and the prescribed dose was 30 Gy in 10 fractions. We compared the parotid dose between 2 radiotherapy plans using different lower field margins: conventional field to the lower level of the atlas (CF) and modified field fitted to the brain tissue (MF). Results: Averages of mean parotid dose of the 2 protocols with CF and MF were 17.4 Gy and 8.7 Gy, respectively (p < 0.001). Mean parotid dose of both glands ${\geq}20$ Gy were observed in 15 (28.3%) for CF and in 0 (0.0%) for MF. The whole brain percentage volumes receiving >98% of prescribed dose were 99.7% for CF and 99.5% for MF. Conclusion: Compared to WBRT with CF, CT-based lower field margin modification is a simple and effective technique for sparing the parotid gland, while providing similar dose coverage of the whole brain.

Real Time Estimation of Temperature Distribution of a Ball Screw System Using Modal Analysis and Observer (모드해석과 관측기에 의한 볼스크류 온도분포의 실시간 예측)

  • An, Jung-Yong;Kim, Tae-Hun;Jeong, Seong-Jong
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.25 no.1
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    • pp.145-152
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    • 2001
  • Thermal deformation of a machine tool structure can be evaluated from the analysis of the whole temperature field. However, it is extremely inefficient and impossible to know the whole temperature field by measuring temperatures at every point. So, the temperature estimator is required, which can predict the whole temperature field from the temperatures of just a few points. In this paper, a 1-dimensional heat transfer problem is modeled with modal analysis and state space equations. And then the state observer is designed to estimate the intensity of heat source and the whole temperature field in real time. The reliability of the estimator is verified by making comparison between solutions obtained from the proposed method and the exact solutions of examples. The proposed method is applied to the estimation of temperature distribution in a ball screw system.

Development and Validation of Reverberation Chamber Type Whole Body Exposure System fer Mobile Phone Frequency (이동전화 주파수에 대한 전자파 잔향실 형태의 전신 노출장치 개발 및 유효성 평가)

  • 정기범;고경배;도현정;백정기;정연춘;최재훈
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.15 no.3
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    • pp.291-300
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    • 2004
  • Due to the rapid growth of mobile communication services, many studies have been performed on the biological effects of EMF(Electromagnetic field) exposure. However, it is not easy to create the field uniformity in radio frequency. To overcome this difficulty, the electric field and SAR(Specific Absorption Rate) distribution is developed to measure the whole body exposure system. In this paper, we developed the whole body exposure system for in-vivo study utilizing reverberation chamber which has a high possibility of practical use by substituting previous the EMC chamber. The field uniformity in the test area of the designed reverberation chamber was satisfied by the simulation and measurement data. In animal study of the whole body exposure for a mouse, the results of FDTD simulation were compared with those of measurement to confirm SAR under the electromagnetic exposure. We analyze the electric field distribution in the interior of the reverberation chamber and treat these results in statistical manner. In the CDMA frequency band(PCS & Cellular band), an average value of the whole body SAR and local peak value for a experimental mouse were presented for various input power.

Fast MR Imaging Technique by Using Locally-Linear Gradient Field (부분적인 경사자계를 이용한 고속 자기공명 영상촬영기법)

  • 양윤정;이종권
    • Journal of Biomedical Engineering Research
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    • v.17 no.1
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    • pp.93-98
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    • 1996
  • The purpose of this paper is to propose a new localized imaging method of reduced imaging time luting a locally-linear gradient. Since most fast MR(Magnetic Resonance) imaging methods need the whole $\kappa$-space(Spatial frequency space) data corresponding to the whole imaging area, there are limitstions in reducing the minimum imaging time. The imaging method proposed in this paper uses a specially-made gradient coil generating a local ramp-shape field and uniform field outside of the imaging areal Conventional imaging sequences can be used without any RF/gradient pulse sequence modifiestions except the change in the number of encoding steps and the field of view.

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Localized MR Imaging Technique by Using Locally-Linear Gradient Field (부분적 경사자계를 이용한 국부자기공명 영상촬영기법)

  • Yang, Y.J.;Lee, J.K.;Jeong, S.T.;Cho, Z.H.;Oh, C.H.
    • Proceedings of the KOSOMBE Conference
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    • v.1995 no.11
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    • pp.247-249
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    • 1995
  • A new localized imaging technique of reduced imaging time using a locally-linear gradient is proposed. Since most fast MR imaging methods need the whole k-space data corresponding to the whole imaging area, there are limitations in reducing the minimum imaging time. The imaging method proposed in this paper uses a specially-made gradient coil generating a local ramp-shape field and uniform field outside of the imaging area. Conventional imaging sequences can be used without any RF/gradient pulse sequence modifications. The proposed localized imaging technique has been implemented on a 2.0 Tesla whole-body system at KAIST and the imaging results show the utility of the proposed technique.

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Anti-stress Effects of Natural Products from Jeju Island in Zebrafish (제브라피쉬에서의 제주도 천연추출물의 항스트레스 효과)

  • Lee, Jeongwon;Lee, Seungheon
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2019.10a
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    • pp.85-85
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    • 2019
  • Objective: In this study, the anti-stress effects of extract of Hydrangeae Dulcis Folium (EHDF) or ethalonic extract of Opuntiaficus-indica (EOF) of natural extracts from Jeju Island were investigated. Methods: We performed measurement of whole-body cortisol level and behavioral experiments including the novel tank test (NTT) or the open field test (OFT) to assess stress responses in zebrafish. To induce physical stress, we used the net handling stress (NHS). Fish were treated with EOF or EHDF for 6 min before they were exposed to stress. And then, we sacrificed fish for collecting body fluid from whole-body or conducted behavioural tests, including novel tank test and open field test, were evaluated to observe anxiety-like behaviours and locomotion. We used the cortisol enzyme-linked immunoassay kit to measure the amount of cortisol in each zebrafish sample. Results: The results indicate that increased anxiety-like behaviours in novel tank test and open field test under stress were prevented by treatment with both EOF and EHDF (P < 0.05). Moreover, compared with the unstressed group, which was not treated with NHS, the whole-body cortisol level was significantly increased by treatment with NHS. Compared with the NHS-treated stressed control group, pre-treatment with each EHDF and EOF for 6 min significantly prevented the NHS-increased whole-body cortisol level (P < 0.05). Conclusions: In conclusion these results suggest that both EOF and EHDF pretreatment may prevent stress responses and that its mechanism of action may be related to its positive effects on cortisol release.

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