• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.127-131
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• 2000

The paper presents both theoretical and experimental study for dynamic instabilities of a vertical cantilevered pipe with two attached lumped masses conveying fluid. The two attached lumped masses can be considered as valves or some mechanical parts in real pipe system. Eigenvalue behaviors depending on the flow velocity are investigated for the change of positions and magnitudes of an attached lumped mass and a tip mass. In order to verify appropriaty of numerical solutions, experiments were accomplished. Theoretical predictions have a good agreement with experimental ones.

• Computational Structural Engineering
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• v.4 no.4
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• pp.117-124
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• 1991

In order to predict properly the effects of ground motion associated with earthquakes on underground radioactive waste disposal facilities, an understanding of the structural behavior of an underground opening in discontinuous rock masses subjected to dynamic loadings is essential. This paper includes literature review on computational models for discontinuous rock masses and on mathematical models for the structural analysis of underground opening. Then, structural analyses of underground openings using the distinct element computer program written for the static and dynamic analysis of discontinuous rock masses have been performed.

• Proceedings of the KSEEG Conference
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• 2005.04a
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• pp.160-160
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• 2005

• Korean Journal of Veterinary Pathology
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• v.5 no.2
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• pp.63-66
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• 2001

Two 53-day-old broiler chickens were condemned due to multiple cutaneous nodular masses at slaughter house. Grossly, variable sized round masses were scattered in the abdomen and pelvis. Some of them were large and fused each other. Center of large fused nodules were ulcerated. Histopathologically, tumor masses consisted of multiple cords or masses of epidermal cells. Some of \ulcornerem contained central conoentric lamella of keratin (cancer pearl). From these results, these cases were diagnosed as cutaneous squamous cell carcinoma. This is the first report of cutaneous squamous cell carcinoma occurred in broiler chickens in Korea.

• Journal of Korean Tunnelling and Underground Space Association
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• v.5 no.4
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• pp.349-360
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• 2003

A practical modeling approach has been proposed in this study to better understand the behavior of penetration grouting which is normally applied to the jointed rock masses to increase the bearing capacity and to reduce the ground water flow into the tunnel. Based on Bingham model together with a steady-state flow of the grout, penetration model is simulated in the commercial package called UDEC and, injection pressure as well as joint thickness are found to be the main parameters to determine the range of grout spread. Another numerical model on fracturing grouting is also suggested and, in this case, the tensile strength as well as cohesion of the rock masses are proven to be the major factors to decide the fracturing mechanism of the rock masses. The reinforcement effect of the grout-reinforced rock masses is calculated from the suggested algorithm on orthotropic material model and it is found that the directional stiffness of reinforced rock masses is increased up to 3 to 4 times compared with original jointed rock masses. Future work will be concentrated on the water control around the tunnel by the grout injection and a model test will also be performed to verify the suggested methods developed in this study.

• Archives of Plastic Surgery
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• v.40 no.4
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• pp.387-391
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• 2013

Background The most common cutaneous malignant masses are basal cell carcinoma (BCC) and squamous cell carcinoma. The predominant site of a malignant mass is the face, which has many opportunities to be exposed to ultraviolet radiation. However the predilection sites of malignant masses have been equivocal due to the use of general regions, rather than anatomical landmarks, in surveys. A facial esthetic unit is an anatomical site classified as an area of similar facial contour characteristics that can be distinguished from other areas. The purpose of this study is to determine widely accepted anatomical landmarks using the esthetic unit. Methods We retrospectively analyzed 118 cases of malignant masses in our clinic from January 2005 to October 2012. We evaluated the patients' age, gender, and predilection site of the malignant mass by esthetic unit through pathology, medical records and patient photographs. We mapped the occurrence site of the malignant mass on schematic drawings of the esthetic units. Results Most of the malignant masses were BCC. The ratio of males to females was 1:1.41. The frequent predilection site of a malignant mass was on the nasal unit (33.1%), followed by the buccal unit (11.0%). Primary closure was the most common method of repairing a surgical defect (38.9%), followed by a local flap (35.5%). Conclusions This review described the relationship between clinical characteristics and esthetic units by proposing objective predilection sites for malignant masses, which can be used commonly as a framework in the study of malignant masses by unifying equivocal occurrence sites.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.18
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• pp.7929-7934
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• 2014

Background: The primary objective of this study was to assess the proportion of malignancies in ovarian masses during $1^{st}$ January 2002, to $31^{st}$ December 2011 at the Department of Obstetrics and Gynecology, King Chulalongkorn Memorial Hospital. A secondary objective was to evaluate associations with patients' clinical characteristics and ovarian malignancy proportion and subtypes. Materials and Methods: Retrospective descriptive study analyzed data of ovarian masses larger than 3 centimeters in maximal diameter, from the division of Gynecologic Cyto-Pathology at KCMH. SPSS software version 17 (SPSS, Inc, Chicago, IL, USA) was used. Results: A total number of 6,115 patients were included. Among the total ovarian masses studied, 13.7% were malignant. After the age of sixty, the proportion reached almost 40%. It was also above 20% in women younger than 20 years old. During premenarche period, proportion of ovarian malignancies was 50%. Only 1% of ovarian masses were found to be malignant during the pregnancy and post-partum periods. Parity decreased the probability of ovarian malignancy during postmenopausal years. Period of menopause did not have any impact on this probability. During the first two decades of life, germ cell malignancy dominated. As the age increased, the percentage of surface epithelial-stromal malignancy increased with a peak at the fifth decade. In contrast, malignant sex cord-stromal cell tumors occurred at a constant rate in each age group after the thirties. Conclusions: Proportion of ovarian cancers in each age group, menstrual and pregnancy status are similar. However there are differences in the distribution of ovarian subtypes especially for the surface epithelial-stromal category.

• Journal of the Korean Society of Radiology
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• v.82 no.5
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• pp.1066-1082
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• 2021

Incidental adnexal masses considered indeterminate for malignancy are commonly observed on ultrasonography. Multiparametric MRI is the imaging modality of choice for the evaluation of sonographically indeterminate adnexal masses. Conventional MRI enables a confident pathologic diagnosis of various benign lesions due to accurate tissue characterization of fat, blood, fibrous tissue, and solid components. Additionally, functional imaging sequences, including perfusion- and diffusion-weighted imaging, improve the diagnostic efficacy of conventional MRI in differentiating benign from malignant adnexal masses. The ovarian-adnexal reporting and data system (O-RADS) MRI was recently designed to provide consistent interpretations in assigning risk of malignancy to ovarian and other adnexal masses, and to provide a management recommendation for each risk category. In this review, we describe the clinical application of multiparametric MRI for the evaluation of adnexal masses and introduce the O-RADS MRI risk stratification system.

• Korean Journal of Veterinary Research
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• v.48 no.3
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• pp.311-316
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• 2008

A 7-year-old female Shih Tzu dog with lots of masses in the whole mammary gland was presented to the surgery department of the Veterinary Teaching Hospital in the Cheju National University. After surgical excision, all mammary samples were referred to Pathology Department of Veterinary Medicine. Grossly, masses were measuring up to $6.5{\times}4{\times}1cm$ and on cut surface of masses in right 1st, 3rd, 4th, 5th and left 1st, 3rd, 4th, 5th mammary masses were well delineated and firm, sulphur yellow, solid round to oval shape. Microscopically, most neoplastic sweat glands were severely proliferated in dermis and subcutis. Most tubules were lined by round to oval shaped epithelium with eosinophilic cytoplasm, hyperchromatic nuclei with high mitotic figures and severe central necrosis. The neoplastic epithelium also had PAS-positive diastase-resistant cytoplasmic granules, but negative with Perls iron stain. The left 2nd mass was well delineated, and had several dark brown areas and yellowish white glittered areas. Mass was well circumscribed with dense connective tissue. Neoplastic areas contained irregular sized mammary gland with papillary grown luminal epithelial cells in single or double cells layer with mitotic figures and small amounts of proliferated myoepithelial cells. Proliferated myoepithelial cells also produced slightly basophilic mucinous materials. Based on the gross, histopathologic and special staining characteristics, this dog was diagnosed as 90% of apocrine sweat gland aenocarcinoma and 10% mammary. complex adenomas in mammary masses. In our best knowledge, this is the first report for concurrent occurrence of apocrine sweat gland adenocarcinoma and mammary gland complex adenoma in mammary masses of the same dog.

• The Bulletin of The Korean Astronomical Society
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• v.35 no.1
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• pp.48.2-48.2
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• 2010

Korean-Japanese Planet Search Program has been carried out since 2005 to search for planets around intermediate-mass giant stars (1.5-5.0 solar masses) by an international collaboration between Korean and Japanese researchers. In this program, we have been carrying out a precise radial velocity survey of about 190 G-type giant stars (6.21.9 solar masses) giant stars. These results extend the planet mass distribution of massive intermediate-mass stars to higher and lower mass region, and may further constrain substellar system formation mechanisms. We report the recent results and current status of Korean-Japanese Planet Search Program.