• Journal of the Korean earth science society
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• v.38 no.5
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• pp.333-344
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• 2017

We present the environmental dependence of the luminosity-size relation of galaxies in the local universe (z < 0.01) along with their dependence on galaxy morphology represented by five broad types (E, dEs, S0, Sp, and Irr). The environmental parameters we consider are the local background density and the group/cluster membership together with the clustercenteric distance for the Virgo cluster galaxies. We derive the regression coefficient (${\beta}$), i.e., the slope of the line representing the least-squares fitting to the data and the Pearson correlation coefficient (c.c.) representing the goodness of the least-squares fit along with the confidence interval from bootstrap resampling. We find no significant dependence of the luminosity-size relation on galaxy morphology. However, there is a weak dependence of the luminosity-size relations on the environment of galaxies, in the sense that galaxies in the low density environment have shallower slopes than galaxies in the high density regions except for elliptical galaxies that show an opposite trend.

• KIEAE Journal
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• v.13 no.2
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• pp.93-100
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• 2013

Many countries have made their best to protect the earth from global warming and to find solutions for the reduction of carbon dioxide emittion and energy consumption. Especially, buildings have emitted over 40% of carbon dioxide against whole quantities emitted to the earth. Therefore, the reduction of carbon dioxide emitted from buildings require to save the earth environment. Energy consumption of buildings in Korea has reached 24% of total energy quantities, and energy consumption of collective housing has been continuously increasing. So, Korea government has also executed the Green Building Certification Criteria(GBCC). The GBCC evaluates the 8 types of buildings - collective housing, office, school, etc - to certificate the green building. In this paper, the evaluation items of collective housing in GBCC were reviewed to be used as the reference data for future revisions by the case studies. According to the results of this study, current version of GBCC requires additional revisions about the evaluations of energy consumption monitoring, commissioning and existing building.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2006.04a
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• pp.391-393
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• 2006

In this study, the performance of artificial neural network (ANN) models for estimating spatial distribution of water quality was evaluated using electric conductivity (EC) values in landfill site. For the ANN model development, feedforward neural networks and backpropagation algorithm with gradient descent method were used. In Test 1, the interpolation ability of the ANN model was evaluated. Results of the ANN model were more precise than those of the Kriging model. In Test 2, spatial distributions of EC values were predicted using precipitation data. Results seemed to be reasonable, however, they showed a limitation of ANN models in extrapolations.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.04a
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• pp.375-378
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• 2005

The objective of this study was to clarify the possibility of adsorption trichloroethylene (TCE) of pretreated granular activated carbon (GAC). The chemical solution used for the acidic treatment was phosphoric acid. In addition, the effect of ultrasound on GAC assessed in this experiments. It was observed that the adsorption of TCE were different based on pH value of pretreated GAC. However, natural water such as groundwater has various factors like ionic strength and hardness etc. Therefore, more laboratory work is needed to study about pretreated GAC.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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• pp.302-305
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• 2003

The purpose of this study was to assess the effect of surfactant on the rate of NAPLs(non-aqueous phase liquids) solubilization. The experimental variables were surfactant type, NAPLs type and water type. The main experimental designs were consists of two phases. The solubilization rate is sensitive to surfactant type based on this test. Used aqueous surfactants were solubilized and removed 72.77 to 89.90% of toluene, PCE(tetrachloroethylene) from the contaminated water during the test, respectively. T60 has higher and stable recovery ratio than SDS in surfactant type but, the micelle of the T60 is more weaker than that of SDS based on this study's results. And the solubilization rate in used water type was almost same.(deionized water, surface water).

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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• pp.334-336
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• 2003

Recently, considerable researches have been focused to find out inexpensive sorbents. for removal of heavy metals in aquatic environments. In particular, various natural materials including geologic media have been attractive. In order to evaluate the applicability of the scoria taken from the Jeju island, Korea, to remove Zn(II) from aqueous solutions, the kinetic sorption experiments were performed in this study. The batch-type kinetic sorption tests were carried out under different conditions, such as different initial Zn(II) concentration, particle size of the scoria, and sorbate/sorbent ratio. The results indicated that the removal of Zn(II) by scoria increased with decreases in initial Zn(II) concentration, particle size of the scoria, and sorbate/sorbent ratio. However, the sorption capacity of the scoria decreased with increasing amount of the scoria. The sorption behavior of Zn(II) onto scoria seemed to be mainly controlled by cation exchange.

• Journal of the Korean earth science society
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• v.28 no.5
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• pp.598-602
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• 2007

A long-term in situ observation was carried out in the Ice-valley at Milyang in order to explain the factors and processes associated with the summertime ice formation. The variation of temperature inside Ice-valley in relation with ice formation in summer time was found to depend on precipitation rate in spring and cold air sinking in autumn and winter. The rate of temperature rising tends to correspond to sensible heat release depending on the precipitation amount at the freezing location. The reason of the cold air accumulation in a talus in the Ice-valley is the cold air sinking over the surface of talus due to the occurrence of outside clod air mass and the accumulated cold air from autumn to spring flow outside at the bottom of talus. The out-flowing cold air can result in the ice formation in the hot summer.

• Journal of the Korean GEO-environmental Society
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• v.20 no.9
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• pp.13-19
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• 2019

Dynamic earth pressure is considered an important parameter in the design of embedded structures. In current engineering design simplified methods developed either for yielding or non-yielding structures are utilized to predict resultant dynamic pressure. The applicability of these equations to embedded structures have not yet been reported. In this study we perform a suite of equivalent linear time history analysis for a range of embedded structure configurations. Numerically calculated dynamic pressure is shown to depend on the flexibility ratio (F), aspect ratio (L/H) of the embedded structure, and ground motion. Increase in L/H and intensity increases the magnitude of dynamic pressure. An increase in F decreases the dynamic pressure. Overall, the trends highlight the need for development of new method that accounts for F and L/H to calculate the dynamic pressure for the performance-based design of embedded structures.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.93.2-93.2
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• 2011

Japan Aerospace Exploration Agency (JAXA) has measured space environment and its effects on spacecraft and astronaut since 1987. At present, we have operated space environment monitors onboard one GEO spacecraft, one QZO spacecraft, and two LEO spacecrafts. The obtained space environment data has been gathered into the Space Environment and Effects System database (SEES, http://sees.tksc.jaxa.jp/). In this presentation, measurement result of space environment in low earth orbit obtained by the Daichi satellite from 2006 through 2011 is reported as well as recent activities in space environment engineerings in JAXA. The Technical Data Acquisition Equipment (TEDA) on board the Daichi satellite (Advanced Land Observing Satellite: ALOS) had been operated in low earth orbit at 700 km altitude with 98 degree inclination from February 2006 until April 2011. The TEDA consists of the Light Particle Telescope and the Heavy Ion Telescope. The operation period of the Daichi satellite was through the solar-activity minimum period. The space radiation environment around the Daichi satellite had been almost stable. However, large solar flares followed by CMEs sometimes disturbed the space radiation environment in the orbit of the Daichi satellite. In addition, high speed solar wind often flowed and modulated the electron flux in the horn region. On the other hand, a little variation was seen in the SAA region.

• Journal of Soil and Groundwater Environment
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• v.16 no.5
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• pp.53-66
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• 2011

Groundwater which infiltrated in recharge areas discharges in the forms of evapotranspiration, baseflow to streams, groundwater abstraction and eventually flows into the sea. This study characterized radon-222 concentration and electrical conductivity (EC) in coastal groundwater discharge, well groundwater, Ilkwang Stream water, and seawater in the coastal area of Busan Metropolitan City and subsequently estimated groundwater discharge rate to the sea. The median value of Rn-222 concentration is highest in well groundwater (18.36 Bq/L), and then decreases in the order of coastal groundwater discharge (15.92 Bq/L), Ilkwang Stream water (1.408 Bq/L), and seawater (0.030 Bq/L). The relationship between Rn-222 concentration and EC values is relatively strong in well groundwater and then in seawater. However, the relationship is not visible between coastal groundwater discharge and Ilkwang Stream water. The groundwater discharge rate to the sea is estimated as $3,130m^3$/day by using radon mass budget model and $16,788m^3$/day by using Darcy's law.