• Journal of the Mineralogical Society of Korea
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• v.11 no.2
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• pp.126-134
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• 1998

Surface site and areas of particles are geometrically calculated for the cubic structures to investigate how the surface sites vary with the variation of morphology and particle size. The numbers of surface site and area become smaller when the particles become equi-dimensional shape. The ratios of surface site to surface area are almost constant except the case of anion of fluorite structure. The ratios of the number of surface site to area are almost constant regardless of particle size except the size of up to 5 to 10 times of the unit cell dimension. This quantification method can be used to obtain data related to the surface reaction.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.15 no.6
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• pp.244-251
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• 2005

The relationship between particle size of hydro-thermally synthesized barium titanate powders (BT01, BT02, BT03, BT04, BT05) and the powder properties was investigated by means of particle size, specific surface area, zeta potential, XPS, XRD and SEM. Particle size determined by laser light scattering is closely related with specific surface area and the tetragonality (c/a) obtained from XRD. The specific surface area of the samples inversely decreased with increasing particle size except BT03 powder. BT03 sample showed higher surface area than BT04 sample of equivalent particle size, which was attributed mostly to the agglomeration of particles in terms of SEM image and XRD analysis. Zeta potential increased with increasing particle size with the exception of BT02 and BT03 which showed larger minus value of zeta potential in comparison with other BT powders. Beta potential results of BT02 and BT03 are considered to be related with the dissolution of $Ba^{2+}$ ion in these powers which was examined by XPS.

• Journal of radiological science and technology
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• v.8 no.2
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• pp.71-72
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• 1985

This study was performed on the dose distribution of various field size and the effect of penumbra shield in the telecobalt unit. The results obtained are as follows. 1. Errors of the light and ${\gamma}-ray$ field size was below the regulation as 0.52 percentage. 2. The coefficient of field area was increased with the larger field area, and this coefficient was showed the more difference in larger SSD. 3. The rectangular field areas, which were described by level of the same percentage depth does, were decreased with the more elongation factor. At the same elongation factor, the compensating factor was decreased with the larger field size. 4. The lead block or extension collimator was able to shield r-ray exposure of outside field size from 50 to 80 percentage. 5. On the matching adjacent fields, while the gap between beam edges are contacted, that overlapped beam edges indicated up to 140 percentage, and while the gap was 1 cm, it could be reduced to 90 Percentage. The lead-libocking on the overlapped area was more effective to lower dose, as 80 percentage in this case. 6. Percentage depth dose of various trimming field sizes were increased linearlly according to area 1 perimeter size, but the center split field size did not maintain linearlly.

• Proceedings of the KSRS Conference
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• v.1
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• pp.228-231
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• 2006

In this paper, requirements of Meteorological Administration about Meteorological Imager (MI) of Communications, Ocean and Meteorological Satellite (COMS) is analyzed for the design of COMS ground station and according to the analysis results, the distribution image size of each observation area suitable for satellite Field Of View (FOV) stated at the requirements of meteorological administration is determined and the precise satellite FOV and the size of distribution image is calculated on the basis of the image size of the determined observation area. The results in this paper were applied to the detailed design for COMS ground station and also are expected to be used for the future observation scheduling and the scheduling of distribution of user data.

• Korean Journal of Materials Research
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• v.23 no.9
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• pp.489-494
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• 2013

In this study, by using nickel chloride solution as a raw material, a nano-sized nickel oxide powder with an average particle size below 50 nm was produced by spray pyrolysis reaction. A spray pyrolysis system was specially designed and built for this study. The influence of nozzle tip size on the properties of the produced powder was examined. When the nozzle tip size was 1 mm, the particle size distribution was more uniform than when other nozzle tip sizes were used and the average particle size of the powder was about 15 nm. When the nozzle tip size increases to 2 mm, the average particle size increases to roughly 20 nm, and the particle size distribution becomes more uneven. When the tip size increases to 3 mm, particles with an average size of 25 nm and equal to or less than 10 nm coexist and the particle size distribution becomes much more uneven. When the tip size increases to 5 mm, large particles with average size of 50 nm partially exist, mostly consisting of minute particles with average sizes in the range of 15~25 nm. When the tip size increases from 1 mm to 2 mm, the XRD peak intensities greatly increase while the specific surface area decreases. When the tip size increases to 3 mm, the XRD peak intensities decrease while the specific surface area increases. When the tip size increases to 5 mm, the XRD peak intensities increase again while the specific surface area decreases.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.04a
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• pp.585-591
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• 1997

The purpose of this experiment is to verify and efficiency of repair for cutting area. The result of this experiment is the fact thar the strength of compression and bending in declined by width and depth of cutting area. Deterioration of strength depends on depth to be repair area the strength of compression decreased up 50% when the repairing area is the fact that it is emerged by the increased of depth size rather than width size.

• Korean Institute of Interior Design Journal
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• v.21 no.4
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• pp.190-199
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• 2012

In this era of information, the public library takes a important role in the local community. In several years, public libraries have been proliferated in our society. However, there have not been specific planning standards of space size for construction of public library. The situation has lead the local governments to the need of consulting for the construction and management of library in search of appropriate guideline. The research paper focuses on the result of consulting support project for construction and management of public library. It examines total 11 libraries which were consulted from 2009 to 2011. It examines the configurational differences between the first scheme from the local government and the final scheme after the consulting, and the percentages of gross areas of each parts of library, reference and reading area, office area, education and cultural area, and public common use area. The analysis concludes that reference and reading area increased by 6.4% from 34.1% to 40.5%, and public common use area reduced by 6.1% from 30.2% to 24.1%, which represents a certain tendency of the configuration ratio of the each parts. Thus, the paper could be a starting point of establishing planning standard of space size for public library.

• Journal of the Korean Applied Science and Technology
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• v.27 no.3
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• pp.310-317
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• 2010

The electrochemical properties of electric double layer capacitor(EDLC) was studied by controlling pore size distribution and specific surface area of the activated carbon fiber(ACF). The mesoporous ACF, which was prepared by the iron exchange method, showed the tendency of increasing average pore size and decreasing total surface area. The mesoporous ACF (surface area = 2225 $m^2$/g, pore size=1.93 nm) showed increased mesopore(pore size=1~3nm) volume from 0.055 cc/g to 0.408 cc/g compared to its raw ACF. The charging capacity of the EDLC which uses the prepared mesoporous ACF also increased from 0.39 F/$cm^2$ to 0.55 F/$cm^2$. From these results, it can be known that the electrochemical properties of EDLC are mainly dependent on the specific surface area, but above the surface area 2200 $m^2$/g, it is the mesopore volume that affects the performance of the capacitor considerably. Because the increased mesopore volume results in a decreased ion mobility resistance, the charge capacitance is enhanced.

• Journal of the Ergonomics Society of Korea
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• v.15 no.1
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• pp.105-117
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• 1996

This study was initiated to investigate (1) whether consumers preferred a specific garment size labeling system and (2) whether consumer's demographic characteristics, clothing behavior, and body size affect their preference of size labeling systems. The survey of consumer's preferences for five size labeling systems included 443 women with 20 to 64 years of age. The result of the survey showed that the subjects' preferences of five size labeling sysems were different significantly. Subjects strongly preferred the old system rather than the revised systems. The subjects least preferred the system with pictogram(system D) and the system with description of the measuring methods of te control dimensions (system E). The subjects/ preference for various garment size labeling systems was different depending on their resident area, educational level, and body size. The garment size labeling system with more information on body measurements (system C) was preferred by the subjects living in the metro city area or subjects having difficulties on purchasing ready-to-wear garments giving reasonable fit. The simplest size labeling system (system A) was strongly preferred by the subjects of low educational level, or the subjects living in the small city.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.11 no.6
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• pp.1-10
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• 2008

The study was aimed at analyzing the relationship between the characteristics of urban green infrastructure and stormwater runoff in a small urban watershed composed of 22 drainage basins. The green areas of which soils are not sealed and allow water infiltrate, were examined for different types of green spaces. In a comparative study for drainage basins of which green spaces are 15.5% and 34.4%, respectively, runoffs were not different with the size of green space. It was attributed to that the increase of runoff by greater road area offset the advantage of greater green area. Another comparative measurement of runoff for drainage basins with similar green area size showed that runoff decreased with greater permeable area (school ground area) and smaller road area. The runoff measurements could address that runoff rates are affected not only by green area size but also by the type of green area and other land covers related to permeability and flow into drainage. It implicated that the improvement of urban green infrastructure as a functional unit for water infiltration and interception is important for stormwater runoff management.