• The Journal of Korean Society for Radiation Therapy
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• v.29 no.1
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• pp.57-68
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• 2017

Purpose: The purpose of this study was to compare volumetric modulated arc therapy(VMAT) with fixed-field intensity modulated radiation therapy(IMRT) using non-coplanar beam when the shape of target is irregular and the location is adjacent to organ at risk(OAR). Materials and Methods: The subjects of this study were a total of 6 patients who had radiation therapy for whole scalp(2 patients), partial scalp(2 patients), and whole ventricle(2 patients) by True Beam STX(Varian Medical Systems, USA). VMAT plans consisted of coplanar or non-coplanar arcs which can minimize the volume of OAR included in beamlets. All fixed-field IMRT plans consisted of non-coplanar beams using more than 2 angles of Couch. Results: The VMAT and IMRT plans were compared with regard to the maximum dose of both lens, both optic nerves, optic chiasm, and brain stem and the mean dose of both eyeballs and hippocampus. VMAT plans showed higher dose than ncIMRT plans at more than 6 of all OARs in every patient, and the ratio was from 1.1 times to 8.2 times. In case of total scalp and partial scalp, the volume of brain which received more than 20 Gy in the VMAT plans was 2 times larger than the volume in the ncIMRT plans. In case of whole ventricle, there was no significant difference. Target coverage was satisfied in both plans($PTV_{100%}=95%$). The maximum dose in target volume and required monitor unit(MU) of ncIMRT were higher than them of VMAT plans. Conclusion: Even though ncIMRT is less efficient than VMAT with regard to required MU and treatment time, the dose to OARs is much lower than VMAT and PTV Coverage is similar with VMAT. If the shape of target is irregular and location is adjacent to OAR, comparison VMAT plan with ncIMRT plan deserves to be considered.

• Korean Journal of Animal Reproduction
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• v.17 no.3
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• pp.221-232
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• 1993

Morphological changes in the uterine and vaginal epithelial cells of the Korean native goats were studied in fifteen primiparous goats slaughtered on the day of parturition and on days 1, 3, 10 and 21 postpartum. 15 uterus and vagina from goats were examined by scanning and transmission electron microscopy. The results obtained in this study were summarized as follows : 1. Transmission electron microscopically, long microvilli which sometimes ramified were found until 10 days postpartum, while short microvilli were found at 21 days. The high electron dense irregular-shaped mitochondria were found in the cytoplasm and the crystalline structure of the mitochondrial matrix was also found from 1 day to 10 days postpartum. Well-developed rough-endoplasmic reticulum (rER) with dilated cisternae which contained the proteins materials was observed at 21 days postpartum. These materials were fused each other and then large granules were found in the free surface of the cytoplasm. A few lipid droplets were generally appeared in the cytoplasm, while numerous droplets were found at 21 days postpartum. A moderate number of ribosomes, a few multivesicular bodies, vesicles, lysosomes and macrophages were found. The globule leucocytes were observed from 0 to 3 days postpartum by transmission electron microscopy. The short microvilli, high electron dense cytoplasm and severe indentation of the nuclear enbelope were found in the vaginal epithelium. Numerouos small vesicles and a few vacuoles were observed in the apical cytoplasmic portion of the epithelium. A few mitochondria were high electron dense and irregular in shape. A moderate amounts of microfilaments, loose intercellular space and dilated rER were also found at 21 days postpartum. 2. Scanning electron microscopically, the folds of the uterine mucosa were generally deep. The long microvilli of the epithelium were found until 3 days postpartum, while short microvili were found at 10 and 21 days postpartum. The distinct intercellular boundary was seen. The apporcine secretory profile of the epithelium observed at between 3 and 10 days postpartum and the cells were somewhat protruded into the lumen. The short microvilli were found on the surface of the protruded cells, while polygonal microridge profile of the epithelium and some dome-shaped epithelium were also observed at 21 days postpartum. The folds of the vaginal mucosa were deep and epithelium was polygonal in shape. The microvilli of the epithelium were long until 3 days postpartum, while they were short at 10 and 21 days. The polygonal epithelium was invaginated into the center of the cell surface until 10 days postpartum. The microridge and dome in shape of the epithelium were found at 10 days postpartum, while the polygonal and exfoliating epithelium were observed at 21 days.

• Journal of the Korean Society of Radiology
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• v.79 no.6
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• pp.303-310
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• 2018

Purpose: To evaluate the CT features of incidental breast lesions on chest CT and to suggest useful criteria for referral to a specialized breast unit. Materials and Methods: Between May 2009 and April 2014, enhanced chest CT examination reports containing the key word 'breast' were reviewed retrospectively. Patients who had incidental breast lesion and were referred to a specialized breast unit and then underwent pathological confirmation or follow-up over a 1-year period were included. Finally, 86 patients (all female, mean age, $48.9{\pm}12.6years$) were enrolled. Two radiologists evaluated lesion characteristics, including size, shape, margins, and enhancement. The correlations between the CT features and pathologies were evaluated, and the diagnostic accuracy of CT features in various combinations was assessed. Results: Among the CT features, irregular shape, non-circumscribed margin, and high contrast enhancement were different between malignant and benign lesions (p < 0.05). The combination of non-circumscribed margin and high contrast enhancement had the highest accuracy (97.7%). Conclusion: Reliable CT features for incidental malignant breast masses are irregular shape, non-circumscribed margin, and high contrast enhancement. The combination of non-circumscribed margin and high contrast enhancement could help distinguish incidental malignant breast lesions and indicate referral to a specialized breast unit.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.16 no.1
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• pp.93-102
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• 1986

The author examined fifty cases of sialolithiasis diagnosed in the Dept. of Oral Radiology in SNUH by conventional radiography and sialography, and analyzed patient's age, sex, location, radio density, numbers, shapes, and relation with ducts and parenchymas. 1. The results of this study were as follows: 1. The average age of patients was 38.6 years in submandibular sialolithiasis, and 39.2 years in parotid sialolithiasis. 2. There was slightly higher incidence in males (58.0%) than in females (42.0%). 3. Salivary stones were found to be much more in the submandibular gland and duct (82.0%) than in the parotid gland and duct (18.0%). 4. Of 62 submandibular salivary stones, 33 (53.2%) occurred in the main duct, 25 (40.3%) occurred in the hilum, and 4 (6.5%) occurred in the parenchyma. Of 18 parotid salivary stones, 9(50.0%) occurred in the main duct, 5(27.8%) occurred in the parenchyma, and 4(22.2%) occurred in the hilum. 5. Of the submandibular salivary stones, the number of radiopaque type was 45 (75.8%), and the number of radiolucent type was 17 (24.2%). Of the parotid salivary stones, the number of radiopaque type was 12 (66.7%), and the number of radiolucent type was 6(33.3%). 6. The single type was 30 cases (73.2%) in submandibular gland, 6 cases (66.7%) in parotid gland, and the multiple type was 11 cases (26.8%) in submandibular gland, and 3 cases (33.3%) in parotid gland. 7. Round shape was 35 cases (43.8%), ovoid shape was 22 cases (27.5%), irregular shape was 17 cases (21.3%), and cylindrical shape was 6 cases (7.5%).

• Research in Plant Disease
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• v.9 no.1
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• pp.28-31
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• 2003

A sclerotinia rot was occurred on the stems of Obedient plant (Physostegia virginiaqna) grown in the exhibition field of Gyeongsangnam-do Agricultural Research and Extension Services, Korea in 2002. The typical symptoms of the disease were that the infected leaves and stems, at first, became dark green, then watery and soft rotted, later, White fluffy mycelia formed on the lesion developed black sclerotia, later, Sclerotia formed on the plants and PDA medium were globose to cylindrical or irregular in shape and 1.0~10.3$\times$1.0~8.4 mm in size. Aphothecia were cup-shape with numerous asci and 0.8~1.8 cm in diameter, Asci were cylindrical in shape and 84~286$\times$4.7~26.3 ${\mu}{\textrm}{m}$ in size. Ascospores were one cell hyaline, ellipsoid to ovoid in shape, and 7.6~12.8$\times$3.4~6.2 ${\mu}{\textrm}{m}$ in size. The optimum temperature far mycelial growth was $25^{\circ}C$. This is the first report on the sclerotinia rot of Physostegia virginiaqna caused by Sclerotinia sclerotiorum in Korea.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.31 no.2
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• pp.47-55
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• 2022

Food impaction due to proximal space opening after implant restoration is a very common phenomenon in patients who have implant prosthesis. This occurs because the movement mechanism between the implant and the tooth is different, and it occurs about 30-60% over time. Contributing factors include the arch (mandible), region (posterior teeth), adjacent teeth (non-vital teeth), and antagonist teeth (natural teeth or implants), etc. While this phenomenon cannot be prevented, efforts should be made to minimize it. In order to have an ideal proximal contact as much as possible, the concave shape or the prominent lower proximal shape should be modified to create a symmetrical proximal shape. with the buccal dentate in the upper third height should be adjusted. Other conditions should be modified so that the heights of the marginal ridges are similar. Since an irregular occlusal plane is a cause of poor prognosis, food impaction should be minimized by restoring the ideal occlusal plane by correcting the extruded antagonist and reduction of the disto-buccal cusp.

• Journal of fish pathology
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• v.32 no.2
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• pp.123-127
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• 2019

In this study, white spots appearing in carapace of imported white leg shrimp Litopenaeus vannamei were observed by macroscopic and microscopic examination. White spots due to white spot disease showed two types, white spots with a regular circular shape ranging from 0.4 mm to 1.7 mm and white spots with an irregular shape ranging from 0.05 mm to 2 mm. White spots due to other causes showed four types that appeared as crystalized materials in range of 100 ㎛ around the tegumental gland, as polygonal inorganic deposits ranging from 58 ㎛ to 188 ㎛, as Linear inorganic deposits ranging from 0.8 mm to 9 mm, as brownish spots ranging from 0.1 mm to 0.4 mm, and brownish spots containing melanin ranging from 0.1 mm to 2 mm. As a result, white spots occurred in imported white leg shrimp Litopenaeus vannamei were divide two type, due to white spot disease or other causes, for quarantine works.

• Transactions of Materials Processing
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• v.7 no.3
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• pp.246-259
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• 1998

This paper describes a research work of developing a computer-aided design and manufacturing of irregular shaped sheet metal product for blanking or piercing and bending operations. An approach to the system is based on the knowledge-based rules. Knowledge for the system is formulated from plasticity theories experimental results and the empirical knowledge of field experts, This system has been written in AutoLISp on the AutoCAD and in customer tool kit on the SmartCAM with a personal computer and is composed of nine modules which are input and shape treatment, flat pattern-layout, pro-processor module. Based on the knowledge-based rules, the system is designed by considering several factors, such as material and thickness of product complexities of blank geometry and punch profile sheet metal to give flat pattern and automatically account for the adjustment of bending allowances to match tooling requirements by checking dimensions and generating NC data automatically according to drawings of die-layout module. Results carried out in each module will provide efficiencies to the designer and the manufacturer of blanking or piercing and bending die in this field.

• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.2
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• pp.575-583
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• 1991

The weld pool convection problem that occurs during the stationary GTA welding has been studied, considering the four driving forces for weld pool convection, i.e., the electromagnetic force, the buoyancy force, the aerodynamic drag force, and the surface tension force at the weld pool surface. In the numerical simulation, the difficulties associated with the irregular moving liquid-solid interface have been successfully overcome by adopting a Boundary-Fitted Coordinate system. In the experiments to show the validity of the numerical analysis, a deep periphery and shallow centerpentrated weld pool shape was observed from the etched specimen. It could be revealed that this type of weld pool shape could be simulated, only when some of aerodynamic drag force distributions are considered. Although slight disagreement arose, the calculated and the observed weld pool shapes were in a reasonable agreement.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.2113_2114
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• 2009

Chalcopyrite based sollar cells have received much attention because of their tunable electronic and optical properties. As a typical ternary chalcopyrite material, $CuInS_2$ has been considered as one of the most popular and promising candidates as absorber materials for photovoltaic applications because of its high absorption coefficient and environmental consideration. In this study, $CuInS_2$ powders have been synthesized using polyol process of a mixture of copper nitrate, indium nitrate, and thiourea with various stoichiometric molar ratios in ethylene glycol at $196^{\circ}C$. As boiling time goes by, the color of metal ion mixed solutions were changed transparent green to dark green and finally turned to black by reduction of OH- radicals. The prepared powders were fully characterized using SEM, XRD. The particle shape of black colored powders showed sphere with about 50 nm in particle size compared to those with dark green colored powders showed irregular shape with about $1{\mu}m$ in particle size. The XRD results showed highly crystallized $CuInS_2$.