• 한국의학물리학회지:의학물리
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• 제14권2호
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• pp.74-80
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• 2003

본 연구의 목적은 핵의학 분야에서 생체 내 흡수선량의 직접 측정에 사용될 수 있는, 테프론을 씌운 TLD의 수행성을 알아보고, 흡수선량 측정 시 테프론의 영향에 대하여 분석하고자 한다. 테프론 캡슐에 든 LiF TLD-100의 반응감도를 고체 팬텀 내에서의 깊이를 달리 하며 측정하였다 성인 인체모형 팬텀을 이용하여 테프론을 씌운 TLD로써 생체 내 흡수선량을 측정하였다. 테프론을 씌우지 않은 보통의 TLD를 이용하여 구한 PDD, TMR, 그리고 생체흡수선량과 테프론을 씌운 TLD로 구한 값을 비교하였다. 보통의 TLD를 이용하여 구한 반응값과 테프론을 씌운 TLD로 구한 값의 차이는 build-up이상의 깊이에서는 같은 조건하에서 3％ 이내였다. 그러나 팬텀 표면 부근에서는 테프론 켑슐의 두께에 기인한 build-up 효과로 인해 큰 차이를 보였다. 본 연구에서 테프론 켑슐로 인하여 수 메가볼트의 방사선에 대한 TLD의 흡수선량 측정에 미치는 변화는 미미한 것으로 나타났다. 따라서 치료 환경 하에서 테프론을 씌운 TLD가 생체 내 선량측정에 매우 적합한 것으로 사료된다.

• 전기학회논문지
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• 제66권6호
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• pp.923-926
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• 2017

In this study, a novel wideband conformal thin antenna is presented for endoscopic capsule application at the 915 MHz Industrial, Scientific and Medical (ISM) band. The thickness of the antenna is only 0.2 mm which can be wrapped inside a capsule's inner wall. By cutting meandered slots on patch, open end slots on ground and utilizing long arm, the proposed antenna can obtain significant size reduction. The net volume of the proposed antenna including substrate and superstrate is only $37.4mm^3$ ($187mm^2$ surface area). This conformal antenna has shown good performance through simulation and measurement with maximum gain of -23 dBi and wide bandwidth from 137 MHz - 205 MHz depending on different environment. In addition, the effect of internal materials specially metallic battery is discussed briefly.

• 설비공학논문집
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• 제7권4호
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• pp.577-588
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• 1995

A numerical study is made on the melting process of an unconstrained ice inside an isothermal ice-ball capsule. The unmelted ice core is continuously ascending on account of buoyancy forces. Such a buoyancy-assisted melting is commonly characterized by the existence of a thin liquid film above the ice core. The present study is motivated to present a full-equation-based analysis of the influences of the initial subcooling and the natural convection on the fluid flow associated with the buoyancy-assisted melting. In the light of the solution strategy, the present study is substantially distinguished from the existing works in that the complete set of governing equations in both the melted and unmelted regions are resolved in one domain. Numerical results are obtained by varying the wall temperature and initial temperature. The present results reported the transition of the flow pattern in a spherical capsule, as the wall temperature was increased over the density inversion point. In addition, time wise variation of the shapes for the liquid film and the lower ice surface, the time rate of change in the melt volume fraction and the melting distance at symmetric line is analyzed and is presented.

• Journal of Plant Biology
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• 제30권3호
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• pp.189-199
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• 1987

Morpho-histogenesis of fruit sculpture and dehiscence in Thespesia populnea is described. The fruit wall is differentiated into epicarp, mesocarp and endocarp. The epicarp is stony, rind-like, 30 to 35 layers thick and derived from outer epidermis, sub-epidermis and ground parenchyma of the ovary wall. The spherical and/of tangentially elongated, thick walled cells of epicarp are interspersed with radial bands of sclereids. The mesocarp is a product of the inner zone of ground parenchyma. At maturity 20 to 25 layers of thin walled parenchyma of mesocarp appear sinuous of disorgnized. The innermost 1 to 3 layers of ground parenchyma and sub-epidermis and inner epidermis form 35 to 40 layers thick endocarp. Due to the differentiation of fibrous tissue in the projection of median plane of carpel wall and a complete ring of fibrous zone in the endocarp, the dry capsule of Thespesia populnea dehises partially in loculicidal fashion.

• Journal of Korean Neurosurgical Society
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• 제47권1호
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• pp.42-47
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• 2010

Objective: To investigate the morphometric characteristics of the pituitary gland and diaphragma sellae in Korean adults. Methods: Using the 33 formaline fixed adult cadavers (23 male, 10 female), the measurements were taken at the diaphragma sellae and pituitary gland. The authors investigated the relationship between dura and structures surrounding pituitary gland, morphometric aspects of pituitary gland and stalk, and morphometric aspect of central opening of diaphragma sellae. Results: The boundary between the lateral surface of pituitary gland and the medial wall of cavernous sinus was formed by the thin dural layer and pituitary capsule. The pituitary capsule adherent tightly to the pituitary gland was observed to continue from the diaphragma sellae. Mean width, length, and height of the pituitary gland were 14.3${\pm}$2.1, 7.9${\pm}$1.3, and 6.0${\pm}$0.9 mm in anterior lobes, and 8.7${\pm}$1.7, 2.9${\pm}$1.1, and 5.8${\pm}$1.0 mm in posterior lobes, respectively. Although all dimensions of anterior lobe in female were slightly larger than those in male, statistical significance was noted in only longitudinal dimension. The ratio of posterior lobe to the whole length of pituitary gland was about 27%. The mean thickness of pituitary stalk was 2 mm. The diaphragmal opening was 5 mm or more in 26 (78.8%) of 33 specimen. The opening was round in 60.6% of the specimen, and elliptical oriented in an anterior-posterior or transverse direction in 39.4%. Conclusion: These results provide the safe anatomical knowledge during the transsphenoidal surgery and may be helpful to access the possibility of the development of empty sella syndrome.