• Journal of Yeungnam Medical Science
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• v.18 no.2
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• pp.199-207
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• 2001

Background: Septoplasty with turbinate surgery is common surgical treatment in patients with septal deviation and chronic hypertrophic rhinitis. The aim of this study was to evaluation objective outcomes of septoplasty with turbinate surgery by analysis of subjective symptom score with objective acoustic rhinometric test before and after surgery, prospectively. Materials and Methods: We reviewed 45 adult patients which were done septoplasty with bilateral turbinectomy or turbinoplasty and followed up at least 3 months by one rhinologist from November 1999 to April 2000, prospectively. We analyzed subjective symptom score, minimal cross-sectional area (MCA), C-notch cross-sectional area, and total volume of both nasal cavity before and after surgery. Correlation test was studied between symptom improvement and acoustic rhinometric results. Results: Twenty nine cases were male and sixteen cases female. The average age was 26.9 year-old (range: 17 to 57 years). There was significantly improvement of symptom score in postoperative 3 months (p<0.05). There was significantly increased C-notch cross-sectional area and total volume in postoperative 3 months. Symptoms improvement were associated with acoustic rhinometric profiles, but, there was not significantly correlation. Conclusion: Septoplasty with turbinate surgery is considered to be effective for nasal obstruction in patients with septal deviation and turbinate hypertrophy. Acoustic rhinometric test is favorable objective test for evaluation of symptom improvement after septal surgery.

• The Korean Journal of Mycology
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• v.34 no.1
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• pp.1-6
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• 2006

In order to select a suitable bioreactor type for the submerged cultivation of Ganoderma applanatum, both growth characteristics and polysaccharides production were compared among four different types of bioreactor. These include an external-loop type air-lift bioreactor (ETAB), a balloon type air bubble bioreactor (BTBB), a column type air bubble bioreactor (CTBB) and a stirrer type bioreactor (STB). The mycelial biomass produced from the reactors were in decreasing order: ETAB ($7\;g/{\ell}$) > BTBB ($6.2\;g/{\ell}$) > STB ($6\;g/{\ell}$) > CTBB ($5\;g/{\ell}$). Maximal soluble exopolysaccharides ($1\;g/{\ell}$) and endopolysaccharides (2.7%) were also obtained from ETAB. Thus, the ETAB was most suitable for submerged culture of G applanatum mycelium. Based on the results, ETAB was chosen for further detailed study. The most effective aeration rate for the mycelial growth in ETAB ranged from 0.05 to 0.1 vvm. For the maximal production, the mycelium at the initial growth stage needed low aeration rate to reduce cell damages by fluid flow. However, as the mycelia grew, the culture became viscous and thus needed higher aeration. The molecular weight of exopolysaccharides obtained from the culture grown in ETAB was higher than that from the culture grown in other bioreactors.

• Explosives and Blasting
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• v.39 no.3
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• pp.15-23
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• 2021

Ventilation shafts are pathways in mines and tunnels for the removal of dust or smoke during underground space construction and operation. In mines, blasting with long blast holes is preferred for the excavation of a ventilation shaft in the 10~20m long crown pillar section. In this case, the bottom part of the blast hole is completely drilled in order to determine the drilling error, and this causes a problem of lowering the explosive charge and blasting efficiency. It is possible to solve the problem of explosive loading and to increase the blast efficiency by covering the curb of the blasthole by using stemming material. In this study, simulations for the blasting of a ventilation shaft were performed with various stemming lengths and the blasthole diameters(45, 76mm) using AUTODYN 2D SPH(Smooth particle hydrodynamics) analysis technique. Also the optimal bottom stemming column was derived by checking the size of the boulder and burden line according to blasting. Analysis result, blasting efficiency is lessened in case of stemming length less than 30cm and the optimal length of the stemming material should be 30cm or higher to achieve high efficiency of blasting.

• 보일러설비
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• no.9 s.164
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• pp.106-116
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• 2007

• Proceedings of the Korean Fiber Society Conference
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• 1997.04a
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• pp.121-126
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• 1997

• The monthly packaging world
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• s.282
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• pp.74-79
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• 2016

• Proceedings of the KSEEG Conference
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• 1999.04a
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• pp.240-242
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• 1999

• Proceedings of the Korean Fiber Society Conference
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• 1996.10a
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• pp.545-550
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• 1996

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.22 no.3
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• pp.207-219
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• 1993

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.21 no.4
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• pp.625-632
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• 2012

Optimization of process parameters in polymer extrusion is an important task to reduce manufacturing cost. To determine the optimum values of the process parameters, it is essential to find their influence on the strength of polymer breathable thin film. The significance of six important process parameters namely, extruder cylinder temperature, extruder speed, extruder dies temperature, cooling roll temperature, stretching ratio, stretching roll temperature on breathable film strength of polymer extrusion was determined. Moreover, this paper presents the application of Taguchi method and analysis of variance (ANOVA) for maximization of the breathable film strength influenced by extrusion parameters. The optimum parameter combination of extrusion process was obtained by using the analysis of signal-to-noise ratio. The conclusion revealed that extruder speed and stretching ratio were the most influential factor on the film strength, respectively. The best results of film strength were obtained at higher extruder speed and stretching ratio.