• Korean Journal of Head & Neck Oncology
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• v.28 no.1
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• pp.37-41
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• 2012

The malignant peripheral nerve sheath tumor(MPNST) is an extremely rare soft tissue sarcoma of ectomesenchyme also known as malignant schwannoma or malignant neurilemoma. It is a highly malignant sarcoma, which is locally invasive, frequently leading to multiple recurrences and eventual metastatic spread. The peak incidence of this disease is known to arise in the seventh decades. In human body, trunk and extremities are the most commonly involved sites, and only 8-14% of all lesions appear in head and neck region. Because immunohistochemical staining is essential in final diagnosis. The authors report a case of malignant peripheral nerve sheath tumor in neck with hypopharyngeal cancer simultaneously on a review of the literature.

• Korean Journal of Construction Engineering and Management
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• v.10 no.3
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• pp.22-31
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• 2009

In the buildings of educational facilities ordered by BTL projects, the competent authorities, private business, and users of school get to have a deep conflict, due to extra expenses resulted from shortening of construction period and establishment of temporary school building, and inconveniences users of school have to undergo during semester. This study aims at solving immediate problems in the aspect of construction method, proposing several alternative plans, including RC construction method generally applied to construction of the existing school, and modular construction method that is emerged as an alternative method for educational facilities lately, along with the method of construction appropriate for BTL projects of educational facilities, calculating cost of construction required for each alternative plan, analyzing and evaluating period of construction.

• Journal of Hydrogen and New Energy
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• v.17 no.2
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• pp.158-165
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• 2006

In order to provide the database for designing microcombustors, the combustion characteristics of premixed methane and propane air microflames at normal and elevated temperatures and atmospheric pressure generated on a microtube were studied experimentally and computationally. The stability limits of premixed microflames and the propensity of the microflames near the stability limits were experimentally determined, while the structure of the microflame at the fuel-leanest limit was obtained using a two-dimensional CFD simulation with a reduced kinetic mechanism. For all the microflames, the stability limits were observed only in the fuel-rich region. Results also show substantial extension of stability limits with elevated temperature that is realistic condition for micro fuel processing and significant fuel dilution immediately near the tube exit due to a low Peclet number times Lewis number effect.

• Annual Conference of KIPS
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• 2003.05a
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• pp.409-412
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• 2003

The 3-D shape use to effect of movie, animation, industrial design, medical treatment service, education, engineering etc... But it is not easy to make 3-D shape from the information of 2-D image. There are two methods in restoring 3-D video image through 2-D image; First the method of using a laser; Second, the method of acquiring 3-D image through stereo vision. Instead of doing two methods with many difficulties, I study the method of simple 3-D image in this research paper. We present here a simple and efficient method, called direct calibration, which does not require any equations at all. The direct calibration procedure builds a lookup table(LUT) linking image and 3-D coordinates by a real 3-D triangulation system. The LUT is built by measuring the image coordinates of a grid of known 3-D points, and recording both image and world coordinates for each point; the depth values of all other visible points are obtained by interpolation.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.24 no.6
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• pp.564-570
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• 2021

Perianal fistulizing diseases, namely perianal fistulas and/or abscesses, are well-known complications of Crohn's disease (CD). These are known to develop more frequently in Asian children with CD, especially in the early stages of the disease course. Approximately half of the pediatric CD cases in Korea present with perianal fistulizing diseases at diagnosis. We report a rare case of a 12-year-old boy with CD with an incidental discovery of a perianal abscess on pelvic magnetic resonance imaging during CD diagnosis. No symptoms or signs of perianal fistulizing disease were identified. The early diagnosis of the perianal abscess enabled timely and effective treatment. Considering the high incidence of concomitant perianal CD in Korean children at diagnosis, perianal imaging may be useful and should be considered during diagnostic evaluation, even in patients with no subjective or objective findings indicating perianal CD.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.21 no.1
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• pp.34-40
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• 2022

In this paper, a flow analysis of a swash-plate type hydraulic piston pump installed on a hydraulic flow supply system for marine vessels is presented. A model and governing equations for computational fluid dynamics (CFD) analyses of swash-plate type hydraulic piston pumps were built, and simulation results regarding the internal flow field of the pump were obtained. By analyzing the internal flow of the swash-plate type hydraulic piston pump, we can confirm the time-dependent stroke of each piston as the pump rotates. We also verified that by analyzing the pulsating flow against the slope of the swash plate, the simulation results match well with the experimental results. The natural frequency of the system was computed to be approximately 380 Hz by applying and analyzing the fast Fourier transform (FFT) of each swash plate slope evaluated.

• Tuberculosis and Respiratory Diseases
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• v.58 no.1
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• pp.68-73
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• 2005

Pulmonary sequestration is a very rare congenital malformation in which a mass of pulmonary tissue is detached from the normal lung and receives its blood supply from a systemic artery. It may be clinically asymptomatic or it has a wide spectrum of various clinical manifestations. The clinical therapeutic approach is to resect the sequestered lobe to prevent frequent complication such as infection. The arterial embolization of feeding artery is a new technique and a less invasive treatment than conventional surgical removal. We have experienced a 17-year-old male with pulmonary sequestration whose complaints were pain in left lower chest. He was diagnosed by computed tomography and aortography and successfully treated with embolization of feeding artery. We report a case of pulmonary sequestration treated with arterial embolization instead of surgery.

• International Journal of Oncology
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• v.54 no.6
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• pp.2169-2178
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• 2019

Forkhead box A1 (FOXA1) functions as a tumor suppressor gene or an oncogene in various types of cancer; however, the distinct function of FOXA1 in colorectal cancer is unclear. The present study aimed to evaluate whether FOXA1 affects the oncogenic behavior of colorectal cancer cells, and to investigate its prognostic value in colorectal cancer. The impact of FOXA1 on tumor cell behavior was investigated using small interfering RNA and the pcDNA6-myc vector in human colorectal cancer cell lines. To investigate the role of FOXA1 in the progression of human colorectal cancer, an immunohistochemical technique was used to localize FOXA1 protein in paraffin-embedded tissue blocks obtained from 403 patients with colorectal cancer. Tumor cell apoptosis and proliferation were evaluated using a terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay and Ki-67 immunohistochemical staining, respectively. FOXA1 knockdown inhibited tumor cell invasion in colorectal cancer cells, and induced apoptosis and cell cycle arrest. FOXA1 knockdown activated cleaved caspase-poly (ADP-ribose) polymerase, upregulated the expression of p53 upregulated modulator of apoptosis, and downregulated BH3 interacting domain death agonist and myeloid cell leukemia-1, leading to the induction of apoptosis. FOXA1 knockdown increased the phosphorylation level of signal transducer and activator of transcription-3. By contrast, these results were reversed following the overexpression of FOXA1. The overexpression of FOXA1 was associated with differentiation, lymphovascular invasion, advanced tumor stage, depth of invasion, lymph node metastasis and poor survival rate. The mean Ki-67 labeling index value of FOXA1-positive tumors was significantly higher than that of FOXA1-negative tumors. However, no significant association was observed between the expression of FOXA1 and the mean apoptotic index value. These results indicate that FOXA1 is associated with tumor progression via the modulation of tumor cell survival in human colorectal cancer.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.6
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• pp.1602-1607
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• 2004

3-O-D-galactopyranosylglyceride (GPG; fatty acids R1, R2 = myristic acid 11.62%, palmitic acid 61.90% and oleic acid 26.48%) was isolated from Chrysanthemum coronarium L that has been used for treating renal and cardiovascular diseases as one of vegetables or medicinal drug. However, little was known about the anti-angiogenic activity of GPG. Thus, anti-angiogenic effect of GPG was evaluated in human umbilical vein endothelial cells (HUVECs) in vitro and in vivo. GPG effectively inhibited bFGF-induced migration and invasion of HUVECs in a concentration-dependent manner, whereas it did not inhibit bFGF-induced proliferation and capillary-like tube formation of HUVECs. To examine the mechanism of anti-angiogenic activity of GPG, gelatin zymography was carried out. GPG downregulated the expression of matrix metalloproteinase-2 in a concentration-dependent manner. Furthermore, GPG significantly disrupted bFGF-induced neovascularization on the chick chorioallantoic membrane assay in vivo. These results suggest that 3-O--D-galactopyranosylglyceride may inhibit neovascularization by inhibiting angiogenic activity of endothelial cells via regulation of matrix metalloproteinase-2 (MMP-2).

• Journal of Powder Materials
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• v.13 no.6 s.59
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• pp.421-426
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• 2006

The microstructural and mechanical properties of Al-Si alloyed powder, prepared by gas atomization fallowed by hot extrusion, were studied by optical and scanning electron microscopies, hardness and wear testing. The gas atomized Al-Si alloy powder exhibited uniformly dispersed Si particles with particle size ranging from 5 to $8{\mu}m$. The hot extruded Al-Si alloy shows the average Si particle size of less than $1{\mu}m$. After heat-treatment, the average particle size was increased from 2 to $5{\mu}m$. Also, mechanical properties of extruded Al-Si alloy powder were analyzed before and after heat-treatment. As expected from the microstructural analysis, the heat-treated samples resulted in a decrease in the hardness and wear resistance due to Si particle growth. The friction coefficient of heat-treated Al-Si alloyed powder showed higher value tough all sliding speed. This behavior would be due to abrasive wear mechanism. As sliding speed increases, friction coefficient and depth and width of wear track increase. No significant changes occurred in the wear track shape with increased sliding speed.