• Korean Journal of Environment and Ecology
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• v.25 no.3
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• pp.404-411
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• 2011

The purpose of this study was to analyze the characteristics of plant covering in the extensive green roof site. Eighteen herbaceous perennial grass such as Caryopteris incara and sedum species such as Sedum Kamtschaticum were planted on an experimental green roof with 10cm substrate depth in 2007. This study investigated vegetation change over 3 growing seasons 2007-2009. The covering rates of planted species mostly increased in 2008, but declined in 2009 except 6 species such as sedum specis and Thymus quinquecostatus var. japonica etc. There were four categories of covering characteristics generated from the results of this study. These include the type of sustain planting site, the type of encroach adjacent site, the type of creeps and spreads, and the type of scatters and spreads. The covering models of eight planted species were drawn by simple regression analysis. However more monitoring of various plants will be needed to establish the information for sustainable roof planting plan.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2003.10a
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• pp.213-219
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• 2003

As the 2-D hydraulic experimental results for the submerged rubble-mound structure, we have concerned with their stability/function characteristics of structures by the effects of wave force, scour/deposition at the toe and wave transmission ratio at the lee-side sea. And as to investigate the variation characteristics of wave transmission ratio which depended to a geometrical structure of the submerged breakwater profiles, the critical conditions for the depth of submergence and crest width obviously presented. In summary, there results lead us to the conclusions that the wave control capabilities of submerged breakwaters by the variation of the submergence depth is high about 4 time degrees at the efficiency than the that of crest width. The destruction of covering block at the crest generated at the region which located between maximum damage curve, it maximum damage/failure station from the toe of the structure were 0.2L. As the wave transmission coefficient and the slope of the structure increase, the damage/failure ratio and the maximum scour depth at the toe was extended, respectively. When maximum scour depth happened. The destruction of covering block which located at the toe generated at the front slope destruction. Finally, it was found from the results that the optimization of structure may be obtained by the efficiently decision of the submergence depth and crest width in the permissible range of wave transmission ratio.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.5
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• pp.528-534
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• 2003

The 2-D hydraulic experimental results for the submerged rubble-mound structure, we have been concerned with the slability/function characteristics of the structures by the effects of wave force, scour/deposition at the toe and the wave transmission ratio at the lee-side sea. So, to investigate the variation characteristics of the wave transmission ratio which depended on a geometrical structure of the submerged breakwater profiles, the critical conditions for the depth of submergence and crest width were obviously presented. In summary, the results lead us to the conclusion that the wave control capabilities of submerged breakwaters by the variation of the submergence depth is higher than about 4 times the degree at the efficiency than the that of crest width. The destruction of the covering block at the crest generated at the region which was located between the maximum and minimum damage curve, and it's maximum damage/failure station from the toe of the structure was $0.2\;L_s.$ As the wave transmission coefficient and the slope of the structure increase, the damage/failure ratio and the maximum scour depth at the toe was extended, respectively. When the maximum scour depth happened, the destruction of the covering block which was located at the toe generated at the front of the submerged rubble-mound breakwater. Finally, it was found from the results that the optimization of the structure may be obtained by the efficient decision of the submergence depth and crest width in the permissible range of the wave transmission ratio.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2003.05a
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• pp.39-43
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• 2003

Chloride ions are considered to be the major cause of steel corrosion in concrete structures exposed to seashore environments and also permeation of chloride is controlled by chloride diffusion. Therefore, the study on chloride diffusion of concrete have been done so far by many researchers. It is reported that coating material as surface covering material is effect about deterioration of salt damage and carbonation, therefore these materials are important in durability of concrete structure. In this study, corrosion characteristics of reinforcement concrete according to types of surface covering material were evaluated by water-cement ratio, chloride penetration by age on the corrosion area rate and mass decrement of reinforcement. And it is considered that the result of this study on application of the corrosion characteristics of reinforcements under salt damage environmental will be suggested as fundamental data of control performance of salt damage. It is performed that comparison and examination of control performance of salt damage by the corrosion characteristics under salt damage environmental.

• Animal Systematics, Evolution and Diversity
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• v.29 no.1
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• pp.23-30
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• 2013

This study reports the discovery of two oxytrichid ciliates, Cyrtohymena primicirrata (Berger and Foissner, 1987) and Oxytricha granulifera Foissner and Adam, 1983, in Jeju Island, Korea. The morphology of the two species was studied using live observation and protargol impregnation. These species are described as follows: Cyrtohymena primicirrata has a body size in live specimens $90-140{\times}40-60{\mu}m$, length : width ratio 2.3 : 1 on average; elongated and slender obovate in outline of body. Cortical granules are shiny yellow on the ventral and dorsal side. Adoral zone of membranelles (AZM) is covering about 48% of the cell with about 38 adoral membranelles. Arrangement of undulating membranes is ordinary Cyrtohymena pattern. Dorsal kineties is six rows with $5{\mu}m$ long bristles. Oxytricha granulifera has a body size in live specimens $90-115{\times}25-38{\mu}m$, length : width ratio 3.31 on average; elongated ellipsoidal in outline of body. Cortical granules are colorless on the ventral and dorsal side. AZM is covering 28% of the cell length in vivo with about 24 adoral membranelles. Arrangement of undulating membranes is Oxytricha pattern. Dorsal kineties is five rows with about $3{\mu}m$ long dorsal bristles.

• Journal of the Korean Solar Energy Society
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• v.25 no.2
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• pp.27-33
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• 2005

To improve the performance of the top-positioning space in buildings, we suggested the environment-friendly system integrating various design techniques in the previous paper. This work discussed to calculate the length of PV considering a part of metallic radiators for radiative cooling, an critical element of the whole system, for shading not to prevent the PV on roof from generating electricity. In the process of calculating the shading area, we used the geometrical relationship between the sun-rays and the variable roof. For general applications, we utilized DL, the ratio of the length of PV and that of metallic radiator on roof, as a design factor, and then used the maximum insolation and the specific insolation($200W/m^2$) to decide the distance off the axis of rotation. As a result, for DL, we found out the reasonable value of 1.0 with full covering, 1.2 with 90%, and 2.0 with 70% in PV covering.

• Journal of Biosystems Engineering
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• v.29 no.1
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• pp.21-28
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• 2004

Spraying is one of the most efficient methods for pesticide and insecticide control. Generally, orchard sprayers(aircarrier sprayer) are used for such applications. However, when an orchard sprayer is used, only 20% of total amount of spray deposits on the target. The rest of spray are not only wasted but are also potential sources of environmental pollution. The research far the development of electrostatic spraying system for orchard sprayer was conducted to develop the new pesticide application technology for the reduction of environmental pollution and f3r the production of safe agricultural products. The spray characteristics for nozzles with the different charging methods were tested and the effect of electrostatic charge was analyzed, in the laboratory experiments. The results of this study indicate that the capacitive type of electrostatic spraying nozzle exhibits a large current deposition of water sprays on the sample target. The covering area ratio by conventional spraying system was 10.2%, while that of electrostatic sprays with pulse induction charging method gave the increased covering area ratio by 4.3 times.

• Journal of Cadastre & Land InformatiX
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• v.48 no.2
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• pp.121-135
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• 2018

The ministry of land, Infrastructure and transport has revised the "National Land Planning and Utilization Act" in 2012. As a result, the regulation of floor area ratio for land covering two or more zoning area has been changed. This study conducted an analysis of the policy effects of changes in the criteria for the application of the floor area ratio by revising the "National Land Planning and Utilization Act". Land covering two or more zoning area means a street side commercial area and street side residential area that is generally understood. This study analyzed the policy effects in Gangnam-gu which has relatively large areas of street side commercial area and street side residential area. The 468 office building transaction cases were analyzed in Gangnam-gu from 2007 to 2017. The result shows that the office building, which has received incentive for policy changes, reported a 19.08% rise in price compared to the one that did not. It means that the economic effects of change of application standard were significant. The existing policy also served as a restriction on land use by landowners, which in turn contributed to the devaluation of the asset's intrinsic value. Therefore, this study may have contributed to the rational use of land and to provide an empirical basis for the change in policy to be assessed for its intrinsic value.

• International Journal of High-Rise Buildings
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• v.3 no.1
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• pp.1-8
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• 2014

When seismic isolation system is applied to high aspect-ratio (height/wide-ratio) steel structures, there are several problems to be taken into consideration. One is lifting up tensile force on the isolation bearing by overturning moment caused by earthquake. Another is securing building stiffness to produce seismic isolation effects. Under these conditions, this paper reports the structural design of high-rise research building in the campus of Tokyo Institute of Technology. With the stepping-up system for the corner bearings, the narrow sides of single span framework are designed to concentrate the dead load as counter-weight for the tensile reaction under earthquake. Also we adopted concrete in-filled steel column and Mega-Bracing system covering four layers on north & south framework to secure the horizontal stiffness of the building.

• Journal of Korea Technology Innovation Society
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• v.8 no.1
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• pp.116-134
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• 2005

This paper investigates the relationships between export and firm characteristics, focusing on technology factors. It is based on a longitudinal data covering listed firms in the Korean manufacturing industry. A regression model for the determinant of export/sales ratio including dynamic adjustment process is tested on a cross-section sample of the year 2001. Empirical findings suggest that there is no significant relationship between export/sales ratio and firm's technological level. The hypotheses concerning human capital intensity and physical capital intensity are also rejected. But we found a positive and inversely U-shaped relationship between firm size and export/sales for basic material and capital good industry. As a dynamic aspect, we found that the pattern of export/sales ratio changed unstably over the last decade. Finally, some policy implications are presented.