• Journal of Environmental Science International
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• v.9 no.5
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• pp.389-392
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• 2000

In this study a packed tower was selected for the treatment apparatus of $NH_3$ gas produced in industry. Formerly latticework packing has been used in preventive facility of treatment of $NH_3$ gas. However recently metallic Ralu-Pack 250YC. structured packing is usually being used in petrochemical production plant. This study is for the application the packing to the $NH_3$ gas treatment in wet scrubbing process. In Air/water system hydraulic pressure drop dependent of specific liquid load and gas capacity factor was continuous and parallel from graph. The tower height can be determuined by the number of transfer unit and the height of transfer unit influenced on liquid distribution.

• Journal of the Korean Society of Tobacco Science
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• v.14 no.1
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• pp.57-65
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• 1992

The quality of cut tobacco will be deteriorated due to weather conditions such as temperature and relative humidity, when shipping and long term storaging. The change of equilibrium moisture contents in cut tobacco were under influence of relative humidity and temperature but not humectants. Therefore internal packing materials are necessary for cut tobacco to maintain initial quality, including taste, flavour and musty smell during shipping or storaging. When packing cut tobacco for shipping or long term storaging, desiralbe packing density was 200/$m^2$, For the long term storage under R.H 90% and 3$0^{\circ}C$, polyethylene film thickness suitable for packing material are above 100$\mu$, which resulted in 42days of shelf life.

• Archives of Plastic Surgery
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• v.38 no.5
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• pp.602-608
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• 2011

Purpose: Nasal bone fracture is the most common type of facial bone fracture and most of nasal bone fracture is combined with septal fracture frequently. Nasal septum is important to support the distal nose and to maintain the nasal airway. But nasal septal fractures are usually unrecognized and untreated at the time of operation. Recently, various materials were using for nasal packing after closed reduction, however these materials are not focused on the correction of nasal bone and nasal septal fracture and many patients are suffered from nasal packing materials. Thus, the purpose of this study is to compare routine packing materials and rolled silastic sheet with respect to postoperative effect of correction of nasal bone fracture and discomfort of nasal packing materials. Methods: We examined 320 patients treated nasal bone fracture from January 2008 to December 2010. For Group I (n=92), $Merocel^{(R)}$ was used for nasal packing, for Group II (n=152) vaseline gauze was used, and Rolled silastic sheet (RSS) with vaseline gauze packing (VGP) was used for Group III (n=76). Under the general anesthesia, all patients were operated by closed reduction and nasal packing was done using three kinds of packing materials. At the time of postoperative 7 days, packing material was removed and studied for pt's satisfaction and postop. complications. Results: In patients with RSS with VGP, the complaints (nasal obstruction, foreign compressive sensation and discomfort during food ingestion) of keeping the nasal packing were decreased ($p$ <0.05) and the postoperative complication (deviation) were decreased comparing to vaseline gauze packing and $Merocel^{(R)}$ packing, however, these differences were not statistically significant ($p$ >0.05). Conclusion: Postoperative nasal packing with RSS with VGP was more comfortable to the patients and it was more effective method to correct the nasal bone fracture and nasal septal fracture.

• Korean Journal of Animal Reproduction
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• v.26 no.2
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• pp.119-124
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• 2002

This study was carried out to investigate the effects of packing materials of frozen boar semen to improve reproductive performance efficiency in pig. Boars were raised at Swine Artificial Insemination Center in National Livestock Research Institute, Sunghwan, Chungnam, Korea. We compared packing protocols for frozen boar semen among 5$m\ell$ maxi-straw, 5$m\ell$ cryogenic-vial, and aluminum-pack. Cryogenic-vial packing material showed similar sperm characteristics compared with maxi-straw packing material when the sperm was frozen above 15cm from liquid nitrogen and thawed at 52$^{\circ}C$ for 190 seconds. We investigated different thawing times to find out the optimal condition of freezing and thawing protocol with cryogenic-vial. Freezing above 15cm from liquid nitrogen and thawing at 52$^{\circ}C$ for 190 seconds were the optimal protocol compared with 120 and 150 seconds. However, normal acrosome rates did not show any differences among thawing times. Post-thawing results of maxi-straw in water at 52$^{\circ}C$ for 45 seconds had better total motility and curve linear velocity than those of cryogenic-vial in water 52$^{\circ}C$ for 190 seconds. However, there were no differences on straightness and normal apical ridge of sperm between maxi-straw and cryogenic vial. Non-return rate, farrowing rate and litter size of sows inseminated with frozen boar semen of commercial farms were higher in the maxi-straw than cryogenic-vial, but there were no significant differences between maxi-straw and cryogenic-vial. In conclusion, there were no significant differences between maxi-straw and cryogenic-vial and so, we may replace cryogenic-vial packing method instead of maxi-straw packing method by improvement of freezing and thawing rate.

• Computers and Concrete
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• v.8 no.6
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• pp.677-692
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• 2011

Particle packing on meso-level has a significant influence on workability of fresh concrete and also on the mechanical and durability properties of the matured material. It was demonstrated earlier that shape exerts but a marginal influence on the elastic properties of concrete provided being packed to the same density, which is not necessarily the case with different types of aggregate. Hence, elastic properties of concrete can be treated as approximately structure-insensitive parameters. However, fracture behaviour can be expected structure-sensitive. This is supported by the present study based on discrete element method (DEM) simulated three-phase concrete, namely aggregate, matrix and interfacial transition zones (ITZs). Fracture properties are assessed with the aid of a finite element method (FEM) based on the damage materials model. Effects on tensile strength due to grain shape and packing density are investigated. Shape differences are shown to have only modest influence. Significant effects are exerted by packing density and physical-mechanical properties of the phases, whereby the ITZ takes up a major position.

• Microbiology and Biotechnology Letters
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• v.45 no.4
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• pp.322-329
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• 2017

Two pilot-scale biocovers (PBCs) were installed in a landfill, and the methane ($CH_4$) concentrations at their inlets and outlets were monitored for 240 days to evaluate the methane removability. Consequently, the packing materials were sampled from the PBCs, and their potential $CH_4$ oxidizing abilities were evaluated in serum vials. The $CH_4$ concentration at the inlet of the biocovers was observed to be in the range of 23.7-47.9% (average = 41.3%, median = 42.6%). In PBC1, where a mixture of soil, earthworm cast, and compost (7:2:1, v/v) was employed as the packing material, the $CH_4$ removal efficiency was evaluated to be between 60.7-85.5%. In PBC2, which was filled with a mixture of soil, earthworm cast, perlite, and compost (4:2:3:1, v/v), the removal efficiency was evaluated to be between 29.2-78.5%. Although the packing materials had an excellent $CH_4$ oxidizing potential (average oxidation rate for $CH_4=180-199{\mu}g\;CH_4{\cdot}g\;packing\;material^{-1}{\cdot}h^{-1}$), $CH_4$ removal efficiency in PBC1 and PBC2 decreased to the range of 0-30% once the packing materials in the PBCs were clogged and channeled. Furthermore, seasonal effects exhibited no significant differences in the $CH_4$ removal efficiency of the biocovers. The results of this study can be used to design and operate real-scale biocovers in landfills to mitigate $CH_4$ buildup.

• Design & Manufacturing
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• v.14 no.1
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• pp.1-7
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• 2020

In this study, the variation of the shrinkage in the thickness direction of the molded parts according to the gate size of the polymer core fabricated through the 3D printer using the SLS method was studied. The polymer cores are laser sintered and the powder material is nylon base PA2200. The polymer cores have lower heat transfer rate and rigidity than the metal core due to the characteristics of the material. Therefore, the injection molding test conditions are set to minimize the deformation of the core during the injection process. The resin used in the injection molding test is a PP material. The packing condition was set to 80, 90 and 100% of the maximum injection pressure for each gate size. The runner diameter used was ∅3mm, and the gates were fabricated in semicircle shapes with cross sections 1, 2, and 3 ㎟, respectively. Thickness measurement was performed for 10 points at 2.5 mm intervals from the point 2.5 mm away from the gate, and the shrinkage to thickness was measured for each point. The shrinkage rate according to the gate size tends to decrease as the cross-sectional area decreases as the maximum injection pressure increases. The average thickness shrinkage rate was close to 0% when the packing pressure was 90% for the gate area of 1mm2. When the holding pressure was set to 100%, the shrinkage was found to decrease by 3% from the standard dimension due to the over-packing phenomenon. Therefore, the smaller the gate, the more closely the molded dimensions can be molded due to the high pressure generation. It was confirmed that precise packing process control is necessary because over-packing phenomenon may occur.

• The monthly packaging world
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• s.151
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• pp.106-121
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• 2005

• The monthly packaging world
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• s.359
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• pp.77-81
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• 2023

• Journal of Sensor Science and Technology
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• v.24 no.6
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• pp.385-391
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• 2015

In this paper, we propose a new method to infiltrate $Fe_3O_4$-nanoparticles into a porous silicon film and a monitoring technique to detect packing density of nanoparticles within the film. Recently, research to use porous silicon as a drug carrier or a new functional sensor material by infiltrating $Fe_3O_4$-nanoparticles has been extensively performed. However, it is still necessary to enhance the packing density and to develop a monitoring technique to detect the packing density in real time. In this light, we forcibly injected a nanoparticle solution into a rugate-structured free-standing porous silicon (FPS) film by applying a pressure difference between the two sides of the film. We found that the packing density by the pressure-infiltration method proposed in this paper is enhanced, relative to that by the previous diffusion method. Moreover, a continuous shift in wavelength of the rugate reflectance peak measured from the film surface was observed while the nanoparticle solution was being injected. By exploiting this phenomenon, we could qualitatively monitor the packing density of $Fe_3O_4$-nanoparticles within the FPS film with the injection volume of the nanoparticle solution.