• Journal of the Korean Ceramic Society
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• v.31 no.9
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• pp.989-994
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• 1994

This study aims at finding the closest packings of regular shape particles such as sphere, circle rod and hexagonal rod type. As the ratio of particle size to container lowered to less than 1/10, the wall effect decreased gradually. The tap density of spherical particles with almost orthorhombic arrangement was 59.5%, while those of circle rod and hexagonal rod type particles were 63.5% and 63.0% respectively. And it was decreased with increasing the aspect ratio of regular particles. The tap density of binary mixtures was larger than that corresponding to the monosized particles packing by about 15%. The tap density of ternary mixtures was larger than that of corresponding to the packing of binary mixtures by about 9%. This work employed the binary mixture of 60% coarse particles and 40% fine particles with size ratio of 1.0 to 1/10 and the ternary mixture of 60% coarse particles, 20% medium and 20% fine particles with size ratio of 1:1/10:1/400 respectively.

• Journal of the Society of Disaster Information
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• v.7 no.1
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• pp.12-20
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• 2011

This study was performed for identifying the characteristics of mass gathering and human injury in mass gathering based on the literature survey and analysis of mass gathering and crowd packing. The size and density of crowd influenced the characteristics of mass gathering according to type of mass gathering. The variables and causes of human injuries of mass gathering have positive or negative influences based on the weather, attendance, duration, location, mobility, event type, crowd mood, alcohol, drug, crowd density and age. Based on the physical mechanism of crowd packing, the degree of crowd packing was influenced by crowd pressure, crowd density and lasting time. But the magnitude of pressure for pedestrian injury criteria remains for further research.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2000.04a
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• pp.205-206
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• 2000

In this paper, we consider variable sized bin packing problem, where the objective is not to minimize the total space used in the packing but to minimize the total cost of the packing when the cost of unit size of each bin does not increase as the bin size increases. A heuristic algorithm is described, and analyzed in two special cases: 1) b$\sub$m/｜…｜b$_1$and w$\sub$n/｜…｜w$_1$, and 2) b$\sub$m/｜…｜b$_1$, where b$\sub$i/ denotes the size of i-th type of bin and w$\sub$j/ denotes the size of j-th item. In the case 1), the algorithm guarantees optimality, and in the case 2), it guarantees asymptotic worst-case performance bounds of l1/9.

• 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 communication and information
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• v.73
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• pp.92-128
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• 2015

We found that world wide popularity was attracted by Korea culture aspects of Psy's . The main factors that caused the syndrome, we noticed that the image of Korea. Expressly, we compared the Korea cultural scene that appeared in and . So, we analyzed successful Korea cultural factors of . For the analysis, we applied the Q methodology. As a result, in , we found 'Recreation Type', 'Advanced Development Type', 'Relieve fatigue type' and 'Adult Type'. Most of these factors have been recognized in Korea cultural factors. we found 'Communal Dancing Type', 'Cheeky Dance Type', 'Pleasant Packing Carriage Type', and 'afflicting type'. However, the Korean factor of were identified only 'Packing Carriage Culture'.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.30 no.12
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• pp.782-787
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• 2017

There is growing interest in power inductors in which metal soft magnetic powder and epoxy resin are combined. In this field, the process technology for increasing the packing density of magnetic particles in an injection molding process is very important. However, little research has been reported in this regard. In order to improve the packing density, we investigated and compared the sedimentation heights of pastes for three types of soft magnetic alloy powders as a function of the mixing ratios and the type of resin used. Experimental results showed that the packing density was the highest (71.74%) when the mixing ratio was 80 : 16 : 4 (Sendust : Fe-S : CIP) according to the particle size using an SE-4125 resin. In addition, the packing density was found to be inversely related to the layer separation distance. As a result, it was confirmed that the dispersion of solid particles in the paste was important for curing; however, the duration of the curing process can greatly affect the packing density of the final composite.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.30 no.12
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• pp.751-756
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• 2017

A molding-type power inductor is an inductor that uses a hybrid material that is prepared by mixing a ferrite metal powder coated with an insulating layer and an epoxy resin, which is injected into a coil-embedded mold and heated and cured. The fabrication of molding-type inductors requires various techniques such as for coil formation and insertion, improving the magnetic properties of soft magnetic metal powder, coating an insulating film on the magnetic powder surface, and increasing the packing density by well dispersing the powder in the epoxy resin. Among these aspects, researches on additives that can disperse the metal soft magnetic powder having the greatest performance in the epoxy resin with high charge have not been reported yet. In this study, we investigated the effect of silanes, KBM-303 and KBM-403, and a commercial dispersant on the dispersion of metal soft magnetic powders in epoxy resin. The sedimentation height and viscosity were measured, and it was confirmed that the silane KBM-303 was suitable for dispersion. For this silane, the packing density was as high as about 72.49%. Moreover, when 1.2 wt% of dispersant BYK-103 was added, the packing density was about 80.5%.

• Korean Journal of Mathematics
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• v.26 no.2
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• pp.271-283
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• 2018

In this paper, we generelize the Olsen's density theorem to any measurable set, allowing us to extend the main results of H.K. Baek in (Proc. Indian Acad. Sci. (Math. Sci.) Vol. 118, (2008), pp. 273-279.). In particular, we tried through these results to improve the decomposition theorem of Besicovitch's type for the regularities of multifractal Hausdorff measure and packing measure.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.5
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• pp.137-141
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• 2012

In order to increase recyclability of new material, aluminium-lithium alloy(Al2050-T84), the chip is compressed in the type of cylinder after machining. This study is to review the effect of environmental condition such as temperature change and salt during the transportation by sea on the corrosion at the surface and inside of the compressed chip, and an effective packing method is presented in this paper.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.36 no.2
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• pp.47-53
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• 2004

In this experiment the effects of the packing structure of pigment on the surface characteristics (smoothness and gloss) of coated paper are studied. Four different kinds of inorganic pigments(clay), ground calcium carbonate(GCC), two of precipitated calcium carbonates(PCC), and two organic pigments(solid bead and hollow type) were used. The method of measuring the relative sediment volume(RSV) was used to analyze the packing structure of coating layer. The relative sediment volume was measured, using the pressure dewatering dry-cake method(PDDM) and centrifuge method. Also, the particle size distribution of coating pigment was determined. The results showed that small amount of organic pigment, added to inorganic pigment, improved smoothness and its effect was greater when GCC was used as inorganic pigment. The efficiency of organic pigment depended upon the inorganic pigment since the organic pigment is packed in the pores formed by the inorganic pigment.