• Journal of the Korean Society for Marine Environment & Energy
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• v.5 no.2
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• pp.3-18
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• 2002

This study has been carried out to find the water Quality in coastal sea of fungmun area, southern Jeju Island. In-situ observations and water sampling had been made every month from July 1997 to June 2000. The distributions of water temperature and salinity over the study area have been 13.8~27.0℃ and 30.0~34.7‰, respectively. Salinity is showed low salinity from June to September (rainy season) because of rain. Tsushima Warm Waters (TWW) as ≥15℃ and ≥34‰ influence the adjacent sea around Jeju Island all year round. Yangtse Coastal Waters (YCW) influence the surface layer around Jeju from June to September and so strong stratification (termocline, halocline) resulted at the depth of between 20~30m at outer-sea. However the stratification does not happen even in summer at inner-sea, which seem to be caused due to vertical mixing by wind, waves and tides. A water mass of high value of water temperature and salinity (respectively 14.1~17.7℃, 33.9~34.1‰) stayed at the lower layer in outer-sea all the year round. It is probably formed by mixing between TWW and YSBCW(Yellow Sea Bottom Cold Water). The mean value of DO was the lowest in summer and the highest in winter. COD and TH were the highest in summer and the lowest in winter. However, TP showed the lowest value in summer season, because the mean value of N/P ratio was over 16. The mean of N/P ratio was under 16 in other seasons. The phosphate would be a limiting factor in the growth of phytoplanHon in summer. Nitrate would be a limiting factor in other seasons. Distribution of chlorophyll a did not show any seasonal change in the study period, but especially increased during April and May in the first year(1998) and the second year(1999) all over the study area, which suggested that phytoplankton inhabitation distributed widely in the study area. The space averaged values were the highest for TIN in rainy season and lower for TP in rainy season than in other seasons. It suggests that river runoff influences the inner-sea.

• Journal of Korean Society of Environmental Engineers
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• v.38 no.3
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• pp.144-149
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• 2016

The metal-impregnated activated carbon was produced from bamboo activated carbon by soaking method of metal nitrate solution. The carbonization and activation of raw material was conducted at $900^{\circ}C$. The specific surface area and pore size distribution of the prepared activated carbons were measured. Also, NO and activated carbon reaction were conducted in a thermogravimetric analyzer in order to use as de-NOx agents of used activated carbon. Carbon-NO reactions were carried out with respect to reaction temperature ($20^{\circ}C{\sim}850^{\circ}C$) and NO gas partial pressure (0.1 kPa~1.8 kPa). As results, the specific volume and surface area of bamboo activated carbon impregnated with copper were decreased with increasing Cu amounts of activated carbon. In NO reaction, the reaction rate of Cu impregnated bamboo activated carbon[BA(Cu)] was promoted to compare with that of bamboo activated carbon[BA]. But the reaction rate of Ag impregnated bamboo activated carbon[BA(Ag)] was retarded. Measured reaction orders of NO concentration and activation energy were 0.63[BA], 0.92[BA(Cu)], and 80.5 kJ/mol[BA], 48.5 kJ/mol[BA(Cu)], 66.4 kJ/mol[BA(Ag)], respectively.

• Journal of Astronomy and Space Sciences
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• v.23 no.2
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• pp.117-126
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• 2006

The Diurnal variation of galactic cosmic ray (GCR) flux intensity observed by the ground Neutron Monitor (NM) shows a sinusoidal pattern with the amplitude of $1{\sim}2%$ of daily mean. We carried out a statistical study on tendencies of the local times of GCR intensity daily maximum aad minimum. To test the influences of the solar activity and the location (cut-off rigidity) on the distribution in the local times of maximum and minimum GCR intensity, we have examined the data of 1996 (solar minimum) and 2000 (solar maximum) at the low-latitude Haleakala (latitude: 20.72 N, cut-off rigidity: 12.91 GeV) and the high-latitude Oulu (latitude: 65.05 N, cut-off rigidity: 0.81 GeV) NM stations. The most frequent local times of the GCR intensity daily maximum and minimum come later about $2{\sim}3$ hours in the solar activity maximum year 2000 than in the solar activity minimum you 1996. Oulu NM station whose cut-off rigidity is smaller has the most frequent local times of the GCR intensity maximum and minimum later by $2{\sim}3$ hours from those of Haleakala station. This feature is more evident at the solar maximum. The phase of the daily variation in GCR is dependent upon the interplanetary magnetic field varying with the solar activity and the cut-off rigidity varying with the geographic latitude.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.4
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• pp.77-84
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• 2018

As the application of BIM (Building Information Modeling) to the civil sector has become practical, and mandatory for road projects, the standardization, development of systems, etc. for the application and operation of BIM are required. In particular, it is important to develop BIM data standards for producing, sharing and managing the lifecycle data of civil facilities because they are commonly national public facilities. The BIM data standards have been developed by utilizing or extending IFC (Industry Foundation Classes), which is an international standard, but schema extensions of river facilities has not been developed thus far. This study proposes an approach to an IFC extension for river facilities using the WBS (Work Breakdown Structure) as a fundamental study for IFC-based schema extension in the river field. For this purpose, the research was carried out as follows. First, the IFC extension development method was selected to represent the river facilities by analyzing the existing IFC structure and previous research cases for the IFC extension. Second, extended elements of the river facilities were identified through an analysis of the WBS and classified according to the high-level structure of the IFC schema. Third, the classified elements were arranged based on the IFC hierarchy and the IFC schema extension for river facilities was established. Based on the suggested extension method of IFC schema, this study developed the schema by defining the element components and parts of river facilities, such as distribution flow elements and deriving their detailed types and properties.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.3 no.1
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• pp.16-24
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• 1998

In this study, Ocean General Circulation Model (OGCM) has been developed as a counterpart of Atmospheric General Circulation (AGCM) for the study of coupled ocean-atmosphere climate system. The oceanic responses to given atmospheric boundary conditions have been investigated using the OGCM. In an integration carried out over 100 simulated years with climatological monthly mean data (EXP 1), most parts of the model reached a quasi-equilibrium climate reproducing many of the observed large-scale oceanic features remarkably well. Some observed narrow currents, however, such as North Equatorial Counter Current, were inevitably distorted due to the model's relatively coarse resolution. The seasonal changes in sea ice cover over the southern oceans around Antarctica were also simulated. In an experiment (EXP 2) under boundary condition of 10-year monthly data (1982-1991) from NCEP/NCAR Reanalysis Project model properly reproduced major oceanic changes during the period, including El Ni$\tilde{n}$os of 1982-1983 and 1986-87. During the ENSO periods, the experiment showed eastward expansion of warm surface waters and a negative vertical velocity anomalies along' the equator in response to expansion of westerly current velocity anomalies as westerly wind anomalies propagated eastward. Simulated anomalous distribution and the time behavior in response to El Ni$\tilde{n}$o events is consistent with that of the observations. These experiments showed that the model has an ability to reproduce major mean and anomalous oceanic features and can be effectively used for the study of ocean-atmosphere coupling system.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.spc1
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• pp.94-98
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• 2005

This study was carried out to provide the geographic information based on the distribution of rice qualities and palatability in Gyeoungbuk province of Korea. The rice grain quality and environmental factors were analyzed using 513 sampling sites based on different five-agroclimtic regions of Gyeoungbuk province during three years from 2002 to 2004. In rice grain quality characteristics, the average palatability was low in South eastern coastal and Tabaek semi alpine regions as $67.6\~68.3$ and the coefficient of variation (CV) was relatively high as $6.2\~7.4\%$. The average head rice rates were low in South and Central eastern coastal regions as $87.3\~88.2\%$ and CV was high as $8.2\~8.3\%$. The average protein content was high in Central eastern coastal regions as $8.0\%$ and CV was high as $8.2\~8.3\%$. In case of palatability, the variation was differed clearly between high and low agroclimatic regions; it means that it is possible to divide the same agroclimatic region of high CV into two or three areas by CV of palatability. As the results of subdividing each existing agroclimatic regions based on the palatability, the variation of grain quality characteristics was become lower than that of existing five-agroclimatic regions. Therefore, the re-establishing of agroclimatic region based on rice grain quality was very important for precise cultivation for rice.

• Development and Reproduction
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• v.5 no.2
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• pp.151-158
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• 2001

Genomic DNA from the blood of crucian carp(Carassius carassiu) from lake and aquaculture facility in Kunsan, Korea was extracted in order to identify genetic differences by polymerase chain reaction-randomly amplified polymorphic DNAs(PCR-RAPD). Out of 12 primers, 6 generated 266 highly reproducible RAPD markers, producing approximately 2.1 polymorphic bands per primer in crucian carp from lake. The degree of similarity varied from 0.18 to 0.76 as calculated by bandsharing analysis in crucian carp from lake. The RAPD outlines obtained with DNA of two different crucian carp populations from Kunsan were different(0.47 from lake and 0.70 from aquaculture facility, respectively). The electrophoretic analysis of polymerase chain reaction-randomly amplified polymorphic DNAs(PCR-RAPD) products showed high levels of similarity between different individuals in crucian carp from aquaculture facility. This result implies the genetic similarity due to raising in the same environmental condition or inbreeding within the crucian carp from aquaculture facility in Kunsan. In other words, crucian carp may have high levels of genome DNA diversity due to the introduction of the wild population from the other sites of Knsan even if it may be the geographical diverse distribution of this species. Generally, the RAPD polymorphism generated by these primers may be useful as a genetic marker for strain or population identification of important aquacultural fish species, crucian carp. However, in future, additional populations and sampling sites will be necessary to complement weak points.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.10 no.3
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• pp.177-184
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• 2000

The effect of the buyancy and thermocapillarity for differnent aspect ratio of flow field on melt motion and mass transfer has been numerically investigated in magnetic Czochralski crystal growth of silicon. During the process of crystal growth, the melt depth of crucible reduces so the aspect ratio of flow field also reduces. Therefore the shape of magnetic field of the flow field changes and the flow pattern also changes significantly. Together with the melt flow which forms the Marangoni convection (or thermocapillary flow) that comes from the inside the flow field, a flow circulation is observed near the corner close both to the crucible wall and the free surface. Due to this circulation, buoyancy effect has been turned out to be local rather than global. As the aspect ratio decreases, the radial component of the magnetic field prevails compared with the axial component in the flow field. Under the influence of this magnetic field, the melt flow and the temperature distribution in a meridional plane tend to depend on the radial position. As the aspect ratio decreases, the temperature gradient near the edge of the crystal decreases yielding smaller thermocapillarity, and the oxygen concentration near the crystal and the oxygen incorporation rate also decrease.

• Journal of the Korean Geotechnical Society
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• v.20 no.7
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• pp.57-68
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• 2004

When an embankment is constructed on soft clay ground, the lateral displacement generally called as lateral flow is generated in the foundation ground. It strongly affects stabilities of structures, such as foundation piles and underground pipes, in and on the foundation ground. The lateral earth pressure induced by the lateral flow is influenced by the magnitude and construction speed of embankment, the geometric conditions and geotechnical characteristics of the embankment, and the foundation ground, and so on. Accurate methods for estimating the lateral earth pressure have not ever been established because the lateral flow of a foundation ground shows very complicated behavior, which is caused by the interaction of shear deformation and volumetric deformation. In this paper, a series of model tests were carried out in order to clarify effects of construction speed of an embankment on the lateral earth pressure in a foundation ground were design. It was found that the magnitude and the distribution of the lateral earth pressure and its change with time are dependent on the construction speed of the embankment. It was found that a mechanism for the lateral earth pressure was generated by excess pore water pressure due to negative dilatancy induced by shear deformation under the different conditions of construction speeds of embankments.

• Journal of Korean Society of Forest Science
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• v.104 no.3
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• pp.375-382
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• 2015

We classified the forest type and figured out the ecological characteristics for each of the types in order to provide the basic informations for being induced ecologically efficient forest practice plan by vegetation units in the natural forest of Songnisan. We established the 250 sample points and collected the vegetation data of vertical distribution for each sample. A variety of multivariate statistical methods were applied to classify the forest types. The species diversity index were analyzed to estimate the stability and maturity for forest vegetation in each the type. The types were divided from two to ten clusters by cluster analysis. The appropriate number of clusters was estimated five clusters by indicator species analysis. It was verified through the multiple discriminant analysis that the estimated number of clusters had been suitable. Based on the species composition for each the type, this study site was classified into five forest types: 1) Quercus serrata and 2) mixed mesophytic forest in the valley area, 3) Q. mongolica forest in the main ridge, 4) Pinus densiflora forest in the sub-ridge extending from the main, and 5) Q. variabilis-P. densiflora forest between the sub-ridge and valley. The species diversity index of the pine forest that had been a simple species composition was the lowest while that of the mixed mesophytic forest of which the composition had been diverse was the highest. As the forest vegetation was more varied, the index showed a tendency to increase.