• Honam Mathematical Journal
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• v.3 no.1
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• pp.23-30
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• 1981

• The Mathematical Education
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• v.26 no.1
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• pp.59-60
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• 1987

• Honam Mathematical Journal
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• v.5 no.1
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• pp.151-154
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• 1983

• Kyungpook Mathematical Journal
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• v.18 no.2
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• pp.183-187
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• 1978

• Kyungpook Mathematical Journal
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• v.20 no.1
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• pp.105-110
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• 1980

• The Korean Journal of Ceramics
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• v.4 no.3
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• pp.240-244
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• 1998

The analytical method was developed to calculate efficiency of densifying carbon/carbon (C/C) composites using coal tar pitch as a matrix precursor at each cyle. Three factors were defined in analyzing the densification process: impregnation efficiency, retention efficiency, and overall densification efficiency. The relationships developed were applied to the experimental results for three densification cycles of C/C composites with pitches as an impregnant to evaluate the factors which may depend on the impregnant and on the route of carbonization. The impregnation efficiency increased with the repeated process cycles whereas the retention efficiency decreased irrespective of the impregnant and carbonization route. Carbonization route P+A+G, in which pressure carbonizationl (P) and graphitization (G) were done before after atmospheric pressure carboniztion (A) respectively, using impregnant of high carbon yields was the most effective method in densifying C/C composites.

• Journal of the Korean Ceramic Society
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• v.32 no.7
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• pp.832-838
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• 1995

The densifying behavior of ultrafine amorphous Si3N4 (about 20 nm)-$\beta$-SiC (about 40~80 nm) powders (O2 : 1.3~15wt%, 0$700^{\circ}C$ within 15 sec and then immediately cooled and held at 135$0^{\circ}C$ for 10 min in N2 atmosphere without resorting to additives using a Xe image heating apparatus. Using an ultrafine pure Si3N4 powder with particle size less than 30nm, further more, mixed with an appropriate amount of $\beta$-SiC, was found to be advantageous to obtain uniform and homogeneous microstructure. In addition, ultrafine Si3N4 powders were also proved to be effective as sintering additive on densifying large sized Si3N4 powder compacts.

• International Journal of High-Rise Buildings
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• v.6 no.2
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• pp.131-138
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• 2017

There is no easy answer to ensuring the world's rapid urban population growth is managed sustainably and in a manner that promotes economic growth, social cohesion, and health and wellbeing. However, densification of existing urban areas is increasingly recognised as an effective and socially responsible way for cities to accommodate growing populations and still operate as vital, vibrant spaces. The Future Spaces Foundation's Vital Cities: Transport Systems Scorecard explores how well-networked, safe and sustainable transport networks equip densifying cities to meet the needs of their rising and fast-changing populations. This paper uses data from the scorecard to examine the transport infrastructure and associated data networks of three large, rapidly densifying cities - Beijing, Mumbai and $S{\tilde{a}}o$ Paulo - and highlight the successful measures and policies implemented between them. It includes an in-depth explanation of the scorecard's methodology, and concludes with an appeal for people-focused transport design that values safety, urban vibrancy and individual wellbeing over corporate efficiency.

• Proceedings of the Materials Research Society of Korea Conference
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• 1993.11a
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• pp.94-94
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• 1993

• Journal of the Korea Furniture Society
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• v.14 no.2
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• pp.21-29
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• 2003

This study was carried out to investigate characteristics of plywood overlaid with softwood veneers densified by resin impregnation and compression. The resin impregnability of Korean pine veneer under atmospheric pressure soaking was greater than that of larch, and impregnability of melamine resin was slightly greater than phenolic resin. It was suggested that resin impregnation ratio was affected by density and thickness of veneer. The largest melamine resin impregnation ratio of 50.7% was obtained with 1.26mm thick Korean pine veneer, and the lowest phenolic resin impregnation ratio of 11.7% with 3.41mm thick larch veneer. Therefore, it was suggested that the vacuum-pres sure-soak treatment is required at thick larch veneer. In densifying resin-impregnated veneers, densification ratio from 13.4 to 31.2% was obtained by high pressure from 15.6 to $20.8kgf/cm^2$. Impregnation of melamine resin also showed relatively greater at densification than that of phenolic resin. So it showed the degree of densification of about 20% or greater. It was seemed that adhesive bonding strength of plywood(base panel) which was directly pressed and overlaid with resin-impregnated veneer was affected by resin tackiness after resin impregnation followed by semi-drying. In laboratory scale, melamine resin impregnation was more favorable for the development of adhesive bonding strength owing to moisture control.