• The KSFM Journal of Fluid Machinery
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• v.1 no.1 s.1
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• pp.72-80
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• 1998

Computational analysis of incompressible flows by numerically solving Navier-Stokes equations using multi-block finite volume method is conducted on a parallel computing system. Numerical algorithms adopted in this study $include^{(1)}$ QUICK upwinding scheme for convective $terms,^{(2)}$ central differencing for other terms $and^{(3)}$ the second-order Euler differencing for time-marching procedure. Structured grids are used on the body-fitted coordinate with multi-block concept which uses overlaid grids on the block-interfacing boundaries. Computational code is parallelized on the MPI environment. Numerical accuracy of the computational method is verified by solving a benchmark test case of the flow inside two-dimensional rectangular cavity. Computation in the axial compressor cascade is conducted by using 4 PE's md, as results, no numerical instabilities are observed and it is expected that the present computational method can be applied to the turbomachinery flow problems without major difficulties.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.240-243
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• 1995

This paper describes the process design and forming limit of the forged hinge produec with the axial protrusion on the sheet metal. Process design is consisted of preform and forging process. In this case, the forged hinge product can be formed in a single workpiece without assembling another axial part to it. Process design of the forged hinge product is analyzed by the commercial FEM program. It is known that process design with perform process, shown by the FEM simulaion, can bring the forming limit of the forged hinge product to a great expansion.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1998.04a
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• pp.81-87
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• 1998

In this paper, a global acoustic design sensitivity analysis (DSA) of field point pressure with respect to structural sizing design variables is developed. Firstly acoustic sensitivity is formulated and implemented numerically. And it is combined with continuum structural sensitivity to obtain the global acoustic, design sensitivity. For this procedure, GASA (global acoustic design sensitivity analyzer) has been developed. A half scale of automobile cavity model is considered in this paper. In order to confirm accuracy of the results of global acoustic DSA obtained by GASA, it is compared with the result of central finite difference method. In order to reduce computation time, Rayleigh approximated solution is evaluated and compared with the solution which used every nodal velocities. Also the acoustic optimization procedure is performed using design sensitivities. From these numerical studies, it can be shown that global acoustic DSA is a useful tool to improve acoustic problems.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.2
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• pp.81.1-81.1
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• 2014

We utilized a 2-D PDR code developed by Lee et al. (2014) to explore the observed OH line fluxes toward embedded protostars. This 2-D PDR code combines self-consistently the FUV radiative transfer, gas-energetics, chemistry, and line radiative transfer. We modeled two sources, GSS30-IRS1 and Elias29, which show conspicuous line emission in the Herschel/PACS wavelength range. The physical and chemical structure for a given embedded source was derived by fitting the PACS CO line fluxes. After exploring various parameter spaces, we conclude that IR-pumping effect either by the central IR source and dust in-situ is insignificant for OH emission, unlike previous studies. We here present a possible solution for the observed OH fluxes, which require a high OH abundance and temperature at the inner-part of the UV heated cavity wall.

• Korean Journal of Veterinary Pathology
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• v.1 no.1
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• pp.77-79
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• 1997

Capillaria hepatica a primary trichuroid nematode parasite in rodents, has been reported in wide range of secondary hosts including humans. We report a rare case of Capillariasis in a 4-year old raccoon dog(Nyctereutes procyonoides) submitted to the Veterinary Diagnostic Laboratory Chonbuk National University for necropsy on July 5, 1996. Grossly the thoracic cavity contained approximately 200 mls of blood-tinged exudate. Edematous lesion was present around aorta and vena cava. liver was slightly swollen and mottled and contained multifocal yellowish-white lesions ranging from 1 to 3 mm in diameter. Histologically liver lesions were localized around central veins and were characterized by cell swelling and necrosis with mixed inflammatory cells surrounding parasite eggs. These eggs were barrel-shaped with polar caps consistent with Capillaria hepatica.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.9
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• pp.4965-4972
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• 2013

This study aimed to discuss the consumption of alcohol as a risk factor for major cancers. We performed a search in the PubMed database, using the following inclusion criteria: meta-analysis published in English in the last 10 years that addressed the relationship between alcohol and the risk of developing cancer. The results indicate that moderate to heavy consumption of alcohol increases the risk of developing cancer of the oral cavity and pharynx, esophagus, stomach, larynx, colorectum, central nervous system, pancreas, breast and prostate. This review did not find any association between alcohol consumption and an increased risk of cancers of the lung, bladder, endometrium and ovary. It was also observed that alcohol consumption may be inversely related to thyroid cancer. Our systematic review has confirmed consumption of alcohol as a risk factor for the development of several types of cancer.

• Korean Journal of Veterinary Service
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• v.21 no.4
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• pp.407-411
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• 1998

Aspergillosis, caused by infection with Aspergillus fumigatus and less commonly by other Aspergillus species, is a prevalent and costly respiratory disease of poultry, In a flock of chicks, the number of birds, 4∼5 months old, had become gradually emaciated and subsequently died. Gross necropsy revealed multiple granulomatous masses on the abdominal serosa. The masses, 4∼15 mm in size, were attached on mainly intestinal wall. Also, the smaller masses in size were on mesentery and pancreas. However, only a few small white nodules were scattered throughout liver and lung in few samples. Microscopically, the mass were granulomatous with a central area of necrosis containing numerous septate, branched fungal hypae consistent with Aspergillus sp. These were surrounded by macrophages, giant cells, lymphocytes and fibrous tissues. Nodular lesions of liver and lung were seemed to spread hemotogenously from intestine and the possible route of infection was speculated by oral. This report is a Aspergillus-induced granuloma limited to the serosa of abdominal cavity, especially of intestinal wall.

• Korean Journal of Optics and Photonics
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• v.3 no.4
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• pp.252-257
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• 1992

In this study, InGaAsP/InP MQW-DH wafer was grown by a vertical type LPE system and 10$\mu$m stripe MQW-LD was fabricated with the wafer. The threshold current was about 200 mA and when the cavity length of the LD was 470$\mu$m the central wavelenth of gain spectra was 1.32$\mu$m the lasing wavelength was 1.302$\mu$m which corresponded to the gain center of the quantum well thickness of 300 $\AA$.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2009.05a
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• pp.91-93
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• 2009

A large steel ingot needs to be larger and larger in size and an ultra high clean, no defect in quality with a low hot top ratio for the resent heavy industry. The demands are very difficult to achieve simultaneously because of their contradictive effect to each other in results. In this study, 30ton steel ingot was cast in a foundry with an optimized design parameter of cast mold and cast process conditions for the low hot top ratio, 12%. The cast ingot was analyzed in macro defect, segregations, and cleanness. No macro defect was founded in central surface of the ingot. The degree of segregation and cleanness are in the controlled range with a sound quality.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.742-743
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• 2006

Filling of the tool die directly influences dimensional tolerances and density variation. To minimize the variations in filling, both within different sections of the cavity and from part to part, are of great importance for produce high quality P/M parts. Filling of the tool die is also one of the limiting factors in the productivity in powder pressing. By using aeration filling in combination with bonded powder mixes, both weight scatter and productivity can be improved. In this presentation results are presented showing the benefit of using aeration filling for different types of powders