• The KSFM Journal of Fluid Machinery
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• v.2 no.3 s.4
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• pp.52-58
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• 1999

The leakage and rotordynamic coefficients of see-through type gas labyrinth seals are determined using a two-control-volume-model analysis with Moody's wall-friction-factor formula which is defined with a large range of Reynolds number and relative roughness. Jet flow theory are used for the calculation of the recirculation velocity in the cavity. For the reaction force from the labyrinth seal, linearized zeroth-order and the first-order perturbation equations are developed for small motion about a centered position. The leakage and rotordynamic coefficient results of the present analysis are compared with Scharrer's theoretical analysis using Blasius' wall-friction-factor formula and Pelletti's experimental results. The comparison shows that the present analysis using Moody's wall-friction-factor formula and Scharrer's theoretical analysis using Blasius' wall-friction-factor formula give the same results for a smooth seal surface and the range of Reynolds number less than $10^5$.

• Proceedings of the Zoological Society Korea Conference
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• 1995.10b
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• pp.338.2-338
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• 1995

No Abstract, See Full Text

• Biomolecules & Therapeutics
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• v.5 no.2
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• pp.107-109
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• 1997

For metabolic study of pinusolide, a naturally occurring platelet activating factor antagonist, a synthetic method for preparation of radiolabeled pinusolide was studied. Pinusolide was first oxidized with $OsO_4/NaIO_4 $to 17-nor-8-oxo compound (2), which was subsequently converted to pinusolide by treatment with the Lombardo reagent $(Zn/CH_2Br_2/TiCI_4)$. The Wittily reaction was unsuccessful in the latter carbonyl methylenation of 2.

• Journal of the Korea Safety Management & Science
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• v.1 no.1
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• pp.29-39
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• 1999

Human sensibility ergonomics is the technique that qualities man's sensibility, measures and evaluates it Quantitatively and makes man's life comfortable, safe and delightful by applying it to products or environmental projects. This study consider the sensibility factor of Sasang constitutional medicine, five elemental properties, and Biorhythm in terms of human sensibility ergonomics. And this study measure reaction-time dependent on a temperament or a state and evaluate the differences of reaction-times objectively with the comparison and analysis using the ANOVA. We can harness it for job design.

• Journal of the Korean Society of Safety
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• v.11 no.4
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• pp.54-63
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• 1996

We establish an expert system for the xylene oxidation reaction process of chemical plants using HAZOP(Hazard and Operability Studies). Our research focus Is only reduced to the cooling system of the total chemical plant due to lack of information. This expert system shows the priority of reasons for the system failure using confidence factor.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.135.2-135.2
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• 2003

We studied the effect of methanol extract of Pachydictyon coriaceum (PC) on atopic allergic reaction. PC dose-dependently inhibited interleukin (IL)-8 and tumor necrosis factor (TNF)-$\alpha$ secretion from the PMA- pius A23187- stimulated HMC-1. PC also dose-dependently inhibited the histamine and $\beta$-hexosaminidase release from mast cells. PC had no cytotoxic effect. (omitted)

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.136.1-136.1
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• 2003

We studied the effect of methanol extract of Sargassum hemiphylum(SH) on atopic allergic reaction. SH dose-dependently inhibited interleukin (IL)-8 and tumor necrosis factor (TNF)-$\alpha$ secretion from the PMA- plus A23187- stimulated HMC-1. SH also dose-dependently inhibited the histamine and $\beta$-hexosaminidase release from mast cells. (omitted)

• Journal of Chest Surgery
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• v.33 no.1
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• pp.1-6
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• 2000

Background: TNF-$\alpha$ plays a major role in producing left ventricular dysfunction cardio-myopathy pulmonary edema and inhibits the compensatory mechanism of congestive heart failure. IL-6 is an acute reactant of immune reaction and also known to control immune reaction but its function in the myocyte was not clearly investigated. Author's performed this experiment to investigate the contents of TNF-$\alpha$ and IL-6 on the assumption that TNF-$\alpha$ and IL-6 may reside in nonfailing heart that has gone cardiac surgery and play some role in cardiac function. Material and Method : Right auricular tissues were sampled from 12 patients who had undergone total corrective surgery for both congenital and acquired heart diseases from January 1998 to June 1998 in Kosin Universcfy Gospel hospital. The quantitive analysis of TNF-$\alpha$ and IL-6 were assessed by ELISA method in right auricular tissue. Hemodynamic values about the pressure of ventricle atrium aorta pulmonary artery and cardiac index pulmonary and systemic vascular resistance and cardiac output were measured by echocardiography and cardiac catheterization and biochemical analyses of LDH & AST were done before operation. statistical analysis was by Paired Student t-test. Patients were divided into children(under 15 years olds) and adults groups and the data was compared beween two groups. Conclusion: Mild pulmonary hypertension and increased pulmonary vascular resistance were existed in both group. The contents of tissue TNF-$\alpha$ IL-6 in each group were independent of each data.

• Membrane Journal
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• v.6 no.4
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• pp.242-249
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• 1996

To improve pervaporation performance of water/ethanol mixtures, chitosan/poly(vinyl alcohol) blended and phosphorylated chitosan composite membranes were prepared. Chitosan/poly(vinyl alcohol) blends were prepared with various blend ratios and then crosslinked with glutaraldehyde by two methods. With increasing crosslinking agent content and crosslinking times separation factor increased and permeate flux decreased. Separation factor of the membrane which contains glutaraldehyde as a crosslinking agent was higher than that of the membrane surface crosslinked. Phosphorylated chitosan was prepared with various reaction times and composite membrane was prepared. As reaction times increased, the separation factor increased with high affinity for water.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.41 no.1
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• pp.11-18
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• 2015

Objectives: The goal of this study was to determine the correlation of clinicopathological factors and the up-regulation of vascular endothelial growth factor (VEGF) expression in oral squamous cell carcinoma. Materials and Methods: Immunohistochemical staining of VEGF and quantitative real-time polymerase chain reaction (RT-PCR) of VEGF mRNA were performed in 20 specimens from 20 patients with oral squamous cell carcinoma and another 20 specimens from 20 patients with carcinoma in situ as a controlled group. Results: The results were as follows: 1) In immunohistochemical study of poorly differentiated and invasive oral squamous cell carcinoma, high-level staining of VEGF was observed. Significant correlation was observed between immunohistochemical VEGF expression and histologic differentiation, tumor size of specimens (Pearson correlation analysis, significance r>0.6, P<0.05). 2) In VEGF quantitative RT-PCR analysis, progressive cancer showed more VEGF expression than carcinoma in situ. Paired-samples analysis determined the difference of VEGF mRNA expression level between cancer tissue and carcinoma in situ tissue, between T1 and T2-4 (Student's t-test, P<0.05). Conclusion: These findings suggest that up-regulation of VEGF may play a role in the angiogenesis and progression of oral squamous cell carcinoma.