• Radiation Oncology Journal
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• v.33 no.3
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• pp.226-232
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• 2015

Purpose: Toxicity of mucosa is one of the major concerns of radiotherapy (RT), when a target tumor is located near a mucosal lined organ. Energy of photon RT is transferred primarily by secondary electrons. If these secondary electrons could be removed in an internal cavity of mucosal lined organ, the mucosa will be spared without compromising the target tumor dose. The purpose of this study was to present a RT dose reduction in near target inner-surface (NTIS) of internal cavity, using Lorentz force of magnetic field. Materials and Methods: Tissue equivalent phantoms, composed with a cylinder shaped internal cavity, and adjacent a target tumor part, were developed. The phantoms were irradiated using 6 MV photon beam, with or without 0.3 T of perpendicular magnetic field. Two experimental models were developed: single beam model (SBM) to analyze central axis dose distributions and multiple beam model (MBM) to simulate a clinical case of prostate cancer with rectum. RT dose of NTIS of internal cavity and target tumor area (TTA) were measured. Results: With magnetic field applied, bending effect of dose distribution was visualized. The depth dose distribution of SBM showed 28.1% dose reduction of NTIS and little difference in dose of TTA with magnetic field. In MBM, cross-sectional dose of NTIS was reduced by 33.1% with magnetic field, while TTA dose were the same, irrespective of magnetic field. Conclusion: RT dose of mucosal lined organ, located near treatment target, could be modulated by perpendicular magnetic field.

• Journal of Embryo Transfer
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• v.23 no.3
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• pp.147-153
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• 2008

Serial ultrasonographic examinations were daily performed from 15 days after ovulation until parturition to determine the growth curve of gestational structures in pregnant Maltese, Yorkshire terrier, Shih-tzu, and Miniature Schnauzer bitches, respectively. Gestational age was timed from the day of ovulation (day 0), which was estimated to occur when plasma progesterone concentration was first increased above 4.0 ng/ml. The inner chorionic cavity diameter were significantly and linearly relative to gestational age especially days 20 to 40, and the fetal head diameter were significantly and linearly relative to gestational age especial1y day 40 to parturition. These results indicate that inner chorionic cavity diameter were the most accurate for estimating gestational age before day 38 of gestation and the fetal head diameter were after day 38 of gestation.

• Applied Microscopy
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• v.18 no.2
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• pp.153-166
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• 1988

The fine structure of the salivary glands of the pine moth, Dendrolimus spectabilis Butler, at the last larval period is observed using light and electron microscopes. The moths have single paired tubular salivary glands which openings are connected to the oral cavity through the upper jaw. By the external morphology and its functions, the glands are subdivided into three regions which are anterior reabsorptive region, middle storage region and posterior secretory region. Along the inner canal of the salivary gland two columns of the large glandular cells are connected each other and oriented to ring-like forms. By this cellular orientation, the glands have long and large tubular structure. From anterior to posterior region large nuclei of the glands are ramified like twigs of the tree, and in the cytoplasm of the cell numerous mitochondria and vacuoles are seen. Moreover, basal plasma membranes of the gland cells are heavily infolded. The anterior region of the glands keeps several characteristics related to the reabsorption of the material from the inner cavity to the glandular cells whereas, main salivary material is synthesized and secreted through the long and convoluted posterior region. The apical plasma membranes of the cells are the most heavily invaginated at the posterior regoin, but trachea and tracheoles are distributed only at the middle and posterior regions. In the cytoplasm of the middle region Golgi complexes appeared at the vicinity of the vesicles, and at the posterior region of the salivary glands multivesicular bodies are also observed.

• Journal of the Society of Naval Architects of Korea
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• v.28 no.2
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• pp.159-173
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• 1991

This paper describes a potential-based panel method formulated for the analysis of a super-cavitating two-dimensional hydrofoil. The method employs normal dipoles and sources distributed on the foil and cavity surfaces to represent the potential flow around the cavitating hydrofoil. The kinematic boundary condition on the wetted portion of the foil surface is satisfied by requiring that the total potential vanish in the fictitious inner flow region of the foil, and the dynamic boundary condition on the cavity surface is satisfied by requiring thats the potential vary linearly, i.e., the tangential velocity be constant. Green's theorem then results in a potential-based integral equation rather than the usual velocity-based formulation of Hess & Smith type. With the singularities distributed on the exact hydrofoil surface, the pressure distributions are predicted with improved accuracy compared to those of the linearized lilting surface theory, especially near the leading edge. The theory then predicts the cavity shape and cavitation number for an assumed cavity length. To improve the accuracy, the sources and dipoles on the cavity surface are moved to the newly computed cavity surface, where the boundary conditions are satisfied again. This iteration process is repeated until the results are converged. Characteristics of iteration and discretization of the present numerical method are much faster and more stable than the existing nonlinear theories. The theory shows good correlations with the existing theories and experimental results for the super-cavitating flow. In the region of small angles of attack, the present prediction shows and excellent comparison with the Geurst's linear theory. For the long cavity, the method recovers the trends of the Wu's nonlinear theory. In the intermediate regions of the short super-cavitation, the method compares very well with the experimental results of Parkin and also those of Silberman.

• Applied Microscopy
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• v.30 no.2
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• pp.153-163
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• 2000

This study aims to demonstrate the effect of squalene (SQ), one of the natural chelator, on the ultrastructural changes in the mouse liver caused by $HgCl_2$. A total of 40 healthy ICR that weighted 30 gm $({\pm}2gm)$ was used for experiment. The experimental group was divided into two groups; group A and B. The group A administrated $HgCl_2$ (4.0mg/kg) to the intraperitoneal. The group B administrated $HgCl_2$ (4.0 mg/kg) to the intraperitoneal treated with SQ (180 mg/kg, 2 times/day). Each group was observed at 24, 48, 72, 96 hours after injected $HgCl_2$. The results were as follows: 1. Group A Nucleus showed condensation of nuclear membrane at the 24 hours. At the 48 hours, observed distinct condensation. But nuclear membrane be seen relative rounded-shape at the 96 hours. At overall the time, inner cavity of mitochondria swollen and development of cristae weakened. Also electron density of matrix was a little low. At the 72 hours, destruction of the inner and outer membrane of mitochondria observed occasionally. Swelling of inner cavity of rER and destruction of lamellae be found from 24 hours to 72 hours, but at the 96 hours, only some swelling 2. Group B Nuclear membrnae and chromatin be seen normal shape at overall the time. Mitochondria showed destruction of the inner membrane until the 48 hours, but mostly normal shapes. Electron density showed high on the all groups. RER be found swelling of inner cavity at the 24 and 48 hours, but found typical lamellae and observed a number of transfer vesicles around rER at the 72 and 96 hours. These results suggest that squalene attenuates the toxic effect of the $HgCl_2$ in the mouse liver.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.365-366
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• 2002

A novel TEM resonator coil was developed for the imaging of small animals. The functional elements of the TEM resonator were 8 inner conductors, distributed in a cylindrical pattern and connected at the ends with capacitors to the cylindrical outer shield. The TEM resonator coil with cavity elements was robust to the surrounding influences due to the self-shielding structure. The TEM resonator coil with high Q factor could provide high quality MR images at 3.0T MRI system. Also, the TEM resonator coil has an advantage for a fine tune with length adjustment of each cavity elements. Thus, The TEM resonator coil at 3.0T, even higher field could be used in the research studies.

• Textile Coloration and Finishing
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• v.19 no.2
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• pp.32-35
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• 2007

Cyclodextrin is a cyclic oligosaccharid material which shows an ability to incorporate organic guest molecules inside their cavity area. Thus, this ${\beta}-cyclodextrin$ treatment on fiber substrates may provide the changed surface characteristics of the substrates such as solubility, chemical reactivity and spectral property. In this context, the aim of this present work is to make a bridge connection using hetero-bi-functional reactive dye between fiber substrates and ${\beta}-cyclodextrin$. In addition, the corresponding Berberine inclusion behaviors into the inner cavity of ${\beta}-cyclodextrin$ was examined. The %exhaustion of Berberine inclusion as a guest molecule within the ${\beta}-cyclodextrin$ was measured using UV-Vis spectrophotometer. The findings showed that the %exhaustion of Berberine inclusion increased with increasing the prepared dye bridge compound and ${\beta}-cyclodextrin$ host material.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.21 no.7
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• pp.77-83
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• 2022

When carbon dioxide in a liquid becomes supersaturated, carbon dioxide gas bubbles are generated in the liquid, and they ascend to the surface as they develop further. At this time, the inner wall of the cup with carbon gas attached is known as the entrapped gas cavity (EGS); once an EGS is established, it does not disappear and will continuously create carbon bubbles. This bubbling phenomenon can be activated or suppressed by changing the properties of the solid surface in contact with the carbonated liquid. In this study, the foaming of carbonated liquid is promoted or suppressed by modifying the wettability of the surface. A micro/nano surface structure is formed on the surface of an aluminum cup to produce a superhydrophilic surface, and a superhydrophobic surface similar to a lotus leaf is synthesized via fluorination. Experiment results show that the amount of carbon dioxide bubble generated differs significantly in the first few seconds depending on the surface, and that the amount of gas generated after it enters the stabilization period is the same regardless of the wettability of the cup surface.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.24 no.9
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• pp.944-950
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• 2013

This paper is a study of a rain sensor using an open-ended coaxial cavity resonator which senses the amount of rain drops linearly. It shows that it will be used as a sensor to sense the amount of rain dropped on the windshield of an automobile based on the principle of varied resonant frequency and the loss according to the amount and characteristics of an dielectric lied on the open side of a resonator. The input and output ports are built in the both sides of the resonator and the input and output coupling probes are formed like 'ㄱ' shape. The response of rain drops were simulated by the radius of inner conductor of 2 mm, 5 mm, and 10 mm respectively and it showed that the raindrop was sensed most linearly and sensitively when the radius of inner conductor is 5 mm, We have measured that the resonant frequency have varied from 3.55 GHz to 3 GHz and the Q value have varied from 42.38 to 24.3 according to the variation of rain drop amount on the fabricated resonator. Therefore, it shows that the designed resonator can be applied as a rain sensor that measures the amount of rain drops linearly by using the resonant frequency as a measurement parameter.

• Proceedings of the KSME Conference
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• 2001.06d
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• pp.382-389
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• 2001

In the present study, local heat transfer rates for co-rotating disks with two modified hubs having ventilation holes are investigated for Rossby number of 0.04, 0.1 and 0.35 to evaluate the influence of incoming flows through hub holes. A naphthalene sublimation technique is employed to determine the detailed local heat/mass transfer coefficients on the rotating disks using the heat and mass transfer analogy. Flow field measurements are conducted using Laser Doppler Anemometry (LDA) and numerical calculations are performed simultaneously to analyze the flow patterns induced by the disk rotation. The basic flow structure in a cavity between co-rotating disks consists of three regions; the solid-body rotating inner region, the outer region with turbulence vortices and the shroud boundary layer region. The heat/mass transfer. rates on the co-rotating disks are very low near the hub due to the solid-body rotation and those increase rapidly in the outer region due to turbulence mixing. The modified hubs with ventilation holes enhances significantly the heat/mass transfer rates on the region near the hub. The results also show that the heat transfer of Hub-2 is superior to that of Hub-1, but Hub-1 is more profitable for destructing the solid-body rotating inner region.