• Korean Journal of Ecology and Environment
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• v.34 no.2 s.94
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• pp.90-97
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• 2001

The seasonal changes in phytoplankton standing crops, species composition, dominant species, species diversity and physico-chemical characteristics in Woopo and Mokpo swamps were studied from January to December, 1998. Phytoplankton of a total 353 taxa were identified, the composition of phytoplankton community was characetrized by green algae and diatoms and quantity composition of standing crops was dominated by green alga Oscillatoria sp. was especially prominent. The standing crops varied from 108 cells/ml and 118 cells/ml to 19,178 cells and 38,393 cells/ml in Woopo and Mokpo swamps, respectively. The maximum algal density was observed in November, Micractinium pusillum and Oscillatoria sp. usually contributed 83.2% to total cell numbers in Woopo swamp. However, the maximum density occurred in May when Oscillatoria sp. formed bloom in Mokpo swamp. The low species diversity of the phytoplankton coincided with maximum standing crops of the filamentous blue-green alga Oscillatoria sp. and green alga Micractinium pusillum in May and November.

• Transactions of the Korean hydrogen and new energy society
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• v.27 no.2
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• pp.169-175
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• 2016

The electrolyte added the chlorosulfuric acid ($HSO_3Cl$) as an additive was tested for the electrolyte in all-vanadium redox flow battery (VRFB) to increase the thermal stability of electrolyte. The electrolyte property was measured by the CV (cyclic voltammetry) method. The maximum value of a voltage and current density in the electrolyte added $HSO_3Cl$ was higher than that in the electrolyte non-added $HSO_3Cl$. The thermal stability of the pentavalent vanadium ion solution, which was tested at $40^{\circ}C$, increased by adding $HSO_3Cl$. The performances of VRFB using the electrolyte added and non-added $HSO_3Cl$ were measured during 30 cycles of charge-discharge at the current density of $60mA/cm^2$. An average energy efficiency of the VRFB was 72.5%, 82.4%, and 81.6% for the electrolyte non-added $HSO_3Cl$, added 0.5 mol of $HSO_3Cl$, and added 1.0 mol of $HSO_3Cl$, respectively. VRFB using the electrolyte added $HSO_3Cl$ was showed the higher performance than that using the electrolyte non-added $HSO_3Cl$.

• Journal of the Korean Ceramic Society
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• v.29 no.5
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• pp.391-395
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• 1992

In order to improve the compactness and uniformity in ceramic green body, we have developed dynamic CIP(Cold Isostatic Pressing) as a new forming method in which the CIP and the vibratory pressing were combined. In dynamic CIP, bulk density on alumina compacts was linearly increased with higher │Pmax-Pbias│and maximum pressure of dynamic-CIP was decreased over one-third of that of conventional CIP to obtain the same bulk density.

• Journal of Biomedical Engineering Research
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• v.9 no.1
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• pp.135-138
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• 1988

In this paper, computerized BEAM was implemented for the space domain analysis of EEG. Trans-formation from temporal summation to two-dimensional mappings is formed by 4 nearest point inter-polaton method. Methods of representation of BEAM are two. One is dot density method which classify brain electrical potential 9 levels by dot density of gray levels and the other is colour method which classify brain electrical 12 levels by red-green colours. In this BEAM, instantaneous change and average energy distribution over any arbitrary time interval of brain electrical activity could be observed and analyzed easily. In the frequency domain, the distribution of energy spectrum of a special band can easily be distinguished normality and abnormality.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.7 no.6
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• pp.49-53
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• 2004

This study was aimed to promote evergreen ferns native to Korea as a material for interior landscape by investigate effects of light quality on the growth of Cyrtomium falcatum and Rumohra aristata, in an indoor environment that artificial light was used, especially. Result of experiments are as follows; 1. Wavelengths were measured as control(=570~580nm), red(=600~610nm), yellow(=550~580nm), green(=500~510nm) and blue(=430~440nm) between different color film. The order of photon flux density was red>yellow>control>green>blue decreased. 2. Although there was no difference in the growth of Cyrtomium falcatum depending on light quality, in case of fronds with sori and new fronds, there were highest under red film. Fresh weight was no significant in all treatments, but dry weight was increased with green>control>yellow>blue>red in order. 3. In case of Rumohra aristata, there was no difference in its growth, however, number of total fronds was highest under green film. Although fresh weight was increased with yellow film, dry weight was highest under green film.

• International journal of advanced smart convergence
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• v.4 no.1
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• pp.120-126
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• 2015

This research is a comparison of the characteristics of the displacement isolines due to powder-die-wall friction that arise during the compaction of ceramic powders in conventional die. It has been done using the CosmosWorks software package of the SolidWorks simulation software. The results of comparative simulation with FEM showed that the comparison of the displacement isolines and distribution of deformation of the ceramic powders. In the case of conventional uniaxial dry compaction for long length cylindrical green compact, considerable bending of the layers in the form of a cone can be observed. It is symmetry along centerline of cylindrical green compact. The distributions of the deformation of the green compacts (diameter 14 mm, height 20 mm) as a result of conventional compaction under ultrasonic vibration with power 1 and 2 kW are reduced to 4% and 6.5% when compared with conventional compaction without ultrasonic vibration respectively. Thus, density distribution can be minimized by increasing the power of ultrasonic vibration.

• Journal of the Korean association of regional geographers
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• v.22 no.3
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• pp.666-680
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• 2016

Four parks were selected to study the current situation after large scale suburban housing development in the 1990s. Since housing development road network have expanded with other facilities. First of all, green space area available per housing unit is 7.11- 22.0 sq. m. These parks neither extend as green corridor with surrounding hillside mountains (the river or lakes) nor act as the wind path from the mountains. Some housing units have reconstructed and the others will be redeveloped in near future which would more challenges for the residents in terms of quality of their life.

• Transactions of the Korean hydrogen and new energy society
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• v.28 no.2
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• pp.200-205
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• 2017

The three electrodes (carbon felt) were tested in all-vanadium redox flow battery (VRFB) to confirm the its usefulness. The electrode property was measured by the CV (cyclic voltammetry) method. The current ratio of maximum peak(IPA/IPC) in GF040BH5 and GF051BH3 had almost the same value compared to that in XF30A. The performances of VRFB using the each electrode were measured during 5 cycles of charge-discharge at the current density of $60mA/cm^2$. An average energy efficiency of the VRFB was 77.8%, 77.3%, and 79.2% for XF30A, GF040BH5 and GF051BH3, respectively. It was confirmed from the data that GF040BH5 and GF051BH3 is well suited for use in a VRFB as a electrode, like XF30A.

• ALGAE
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• v.28 no.1
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• pp.121-129
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• 2013

Intact phycobilisomes from a wild-type red Chondrus crispus and its vegetatively derived green mutant were isolated by centrifugation through a discontinuous sucrose density gradient. Pigment composition was subsequently characterized by spectrophotometry. Vegetative thalli of the two strains grown together for six months in the laboratory resulted in different pigment profiles. Two pigmented phycobilisome bands appeared in the sucrose gradient of the wild-type alga, a purple coloured one, and a pink one, whereas only a single blue band appeared in the gradient of the green mutant. Spectrophotometric and fluorescence analyses identified the phycobiliprotein composition of the purple band as the typical phycoerythrin-phycocyanin-allophycocyanin complement in the wild-type, but there was no detectable phycoerythrin present in the blue band of the green mutant. Sodium dodecyl sulphate, preparative polyacrylamide gel electrophoresis analysis confirmed the presence of allophycocyanin subunits in all extracts, but firm evidence of an R-phycoerythrin linker polypeptide in the blue band was missing. These results highlight the ability of C. crispus to adapt to a phycoerythrin deficiency by adjusting light harvesting pigment ratios.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.6 no.6
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• pp.497-501
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• 2005

Dry film method was applied to fabricate lead-free transparent dielectric fur PDP(Plasma Display Panel). From various slurry compositions, it was able to find out the. best composition for producing high density green sheet. The slurry exhibited shear thinning characteristics which are known to be suitable fur producing a high quality green sheet. The thermal expansion coefficient of the fabricated transparent dielectric was measured to be $97{\times}10^{-7}/^{\circ}C$ which is close to the value of the glass substrate(PD-200). Cross sectional SEM of the transparent dielectric layer on PD-200 showed that the two layers were well attached each other with no observable gaps between them.