• 대한방사선치료학회지
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• 제17권1호
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• pp.9-17
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• 2005

목적 : 방사선치료에 있어 치료부위내의 균등한 선량분포는 환자의 치료성적 및 장해를 좌우하는 매우 중요한 인자이다. 이러한 치료부위내의 균등한 선량분포를 얻기 위해 사용하는 여러 가지 방법 중 간단한 Field-in-Field Technique의 유용성을 평가하고 다양한 크기의 전뇌(whole brain)치료 환자에게 적용가능성을 알아보고자 한다. 대상 및 방법 : 전뇌(whole brain)의 일반적인 치료기법인 대향2문조사와 Field-in-Field Technique을 적용했을 때의 선량분포도를 비교하기 위하여 phantom(acryl 16 cm spheral phantom)을 대상으로 치료계획을 수립하였으며, 선량분포평가를 위하여 저감도필름(X-Omat V-film)과 열형광선량계(TLD)를 사용하여 측정하였다. 또한 다양한 두께의 환자20명(대, 중, 소 및 소아-각각 5명)을 대상으로 Field-in-Field Technique의 적용가능성을 평가 하였다 결과 : 전뇌(whole brain)치료에 대향2문조사와 Field-in-Field Technique을 적용한 경우 각각의 치료부위내의 선량분포 및 DVH를 비교한 결과, Field-in-Field Technique을 사용한 경우 고선량(high dose)영역을 $3{\sim}4\%$이하로 줄일 수 있었고, 저감도필름(X-Omat V-film)과 열형광선량계(TLD)에 의한 측정결과 또한 유사한 수치를 얻을 수 있었다. 이러한 Field-in-Field Technique을 다양한 두께의 환자에게 동일하게 적용해도 선량분포의 변화는 $1{\sim}2\%$로 나타났다. 결론 : 전뇌(whole brain)치료에 Field-in-Field Technique를 이용하여 치료계획을 수립하여 적용하면 치료부위내의 균등한 선량분포를 얻을 수 있으므로 추가적인 치료가 필요한 경우 선량합성이 용이하여 쉽게 치료계획을 수립할 수 있었다. 그리고 균등한 선량분포를 얻기 위해 사용하는 wedge filter 및 3D compensator 의 역할을 대체 할 수 있으며, 방사선 치료 시 고선량 영역으로 인해 발생되는 장해를 최소화할 수 있을 것으로 사료된다.

• 한국초지조사료학회지
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• 제13권2호
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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.

• 산업경영시스템학회지
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• 제39권3호
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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.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2000년도 춘계학술대회논문집 - 한국공작기계학회
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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.

• Radiation Oncology Journal
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• 제31권1호
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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.

• 대한기계학회논문집A
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• 제25권1호
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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.

• 한국전자파학회논문지
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• 제15권3호
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• pp.291-300
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• 2004

이동통신 서비스의 급격한 증가로 인해, EMF(Electromagnetic field)노출의 생물학적 효과에 대한 많은 연구들이 수행되어져 왔다. 그러나 연구 수행에 있어서 필요한 무선 주파수 대역에서의 균일장 생성은 쉬운 일이 아니다. 이러한 어려움을 극복하기 위해 전신노출 시 스템에서의 전기장과 SAR(Specific Absorption Rate) 분포 측정이 발전을 해왔다. 본 논문에서는 EMC 대용 챔버로의 활용 가능성이 높은 전자파 잔향실 챔버를 이용하여 동물 실험용 전신 노출 장치를 개발하였다. 설계된 전자파 잔향실은 시뮬레이션과 측정 데이터를 이용하여 시험영역의 균일장에 대한 유효성을 검증하였다. 마우스에 대한 전신노출 실험에 있어서, 노출된 전자파에 대해 SAR을 확인하기 위해서 FDTD수치해석 방법과 측정 결과를 비교하였다. 전자파 잔향실 내부에서의 전기장 분포 특성을 해석하고, 이러한 해석 결과들을 통계적으로 처리하였다. CDMA 이동전화 주파수 대역에서(PCS ＆ Cellular 대역) 입력 파워 변화에 따른 실험상태에서의 마우스 전신 SAR 평균값 및 국부 최대값을 제시하였다.

• 대한의용생체공학회:의공학회지
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• 제17권1호
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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.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1995년도 추계학술대회
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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.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2019년도 추계학술대회
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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.