• Atmosphere
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• v.26 no.4
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• pp.697-709
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• 2016

This study estimates and evaluates the extreme value of 30 m-resolution daily maximum and minimum temperatures over South Korea, using inverse distance weighting (IDW), parameter-elevation regression on independent slopes model (PRISM) and generalized extreme value (GEV) method. The three experiments are designed and performed to find the optimal estimation strategy to obtain extreme value. First experiment (EXP1) applies GEV firstly to automated surface observing system (ASOS) to estimate extreme value and then applies IDW to produce high-resolution extreme values. Second experiment (EXP2) is same as EXP1, but using PRISM to make the high-resolution extreme value instead of IDW. Third experiment (EXP3) firstly applies PRISM to ASOS to produce the high-resolution temperature field, and then applies GEV method to make high resolution extreme value data. By comparing these 3 experiments with extreme values obtained from observation data, we find that EXP3 shows the best performance to estimate extreme values of maximum and minimum temperatures, followed by EXP1 and EXP2. It is revealed that EXP1 and EXP2 have a limitation to estimate the extreme value at each grid point correctly because the extreme values of these experiments with 30 m-resolution are calculated from only 60 extreme values obtained from ASOS. On the other hand, the extreme value of EXP3 is similar to observation compared to others, since EXP3 produces 30m-resolution daily temperature through PRISM, and then applies GEV to that result at each grid point. This result indicates that the quality of statistically produced high-resolution extreme values which are estimated from observation data is different depending on the combination and procedure order of statistical methods.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.14 no.10
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• pp.1089-1095
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• 2003

In this paper, the 26 GHz band omnidirectional antenna that produces an isotropic radiation pattern in the azimuth plane and a directive radiation pattern in the elevation plane was designed by using reflector antennas. To investigate the reliability of the designed antenna, that was analyzed by using the aperture field method and the calculated value was compared with the measured value. An good agreement was achieved between the calculated characteristics and the experimental performance. We found that the designed antenna in this paper can be used as the omnidirectional antenna with reflectors and the analysis method in this paper can be used for the analysis of this type antenna.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2006.11a
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• pp.659-662
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• 2006

Plant industry is very important industry that dominate 70% of standard foreign countries construction acceptance an order woe 2004 years. Technique of plant industry is state that secure part equipment connection detailed design and construction class' competitive power. But, high added value creation among plant industry need technique elevation because available plan, basic design technology is insufficient. Therefore, high added value creation wishes to present problem of standard code and improvement direction for plant design to improve available plan, basic design technology competitive power.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2004.11a
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• pp.381-384
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• 2004

The goal of this study is to generate a landslide susceptibility map using GIS(geographic information system) based method. A simple and efficient algorithm is proposed to generate a landslide susceptibility map from DEM(digital elevation model) and existing maps. The categories of controlling factors for landslides, aspect of slope, soil, topographical index, landuse, vegetation are defined, because those factors are said to have relevance to landslide and are easy to obtain theirs sources. The weight value for landslide susceptibility is calculated from the density of the area of landslide blocks in each class. Finally, a map of susceptibility zones is produced using the weight value of all controlling factors, and then each susceptibility zone is evaluated by comparing with the distribution of each controlling factor class.

• Korean Journal of Microbiology
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• v.26 no.4
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• pp.339-347
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• 1988

The rate of bacterial degradation of hydrocarbon was estimated for the measurment of the self-purification capacity of the aquatic ecosystem. Strain ND601P-2, selected as petroleum degrading bacteria from Nakdong River Estuary with high degradability of petroleum, transformed 42% of hexadecane to $CO_{2}$ or cell mateials under the conditions of $25^{\circ}C$, 0.03M NaCl, 167mg-$NH_{4}^+/1, 950 mg-PO_{4}^{3-}$/1, 50 mg-hexadecane/1. The mineralization rate was found to be significantly affected by the temperature and the $Q_{10}$ value was 2.2. Teh optimal salinity of the strain ND601P-2 was 2o/oo. The increased salinity caused the elevation of % respiration value and the prolonged lag phase.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2007.11a
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• pp.1011-1014
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• 2007

Design VE system in order to promote the economical efficiency and the functional elevation of construction facilities apply to conatruction over 10 billion from december 2005. But it don't achieve purpose of VE original to maximization of value creation through VE because VE perform formal and result center. This study suggests some idea and analyse implementation of design VE through design VE case of turnkey and alternative project performed in domestic.

• Korean Journal of Environment and Ecology
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• v.12 no.4
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• pp.373-380
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• 1999

The Byokryon-Daejangbong valley forest in Keumsan area at Hallyo-Haesang National Park was studied to investigate forest structure in relation to altitude and part of the slope. Forty-eight quadrats were set up in the valley forest along altitude of 200m to 650m and part of the slope. Density, mean DBH, and basal area of the canopy trees were 820~1873trees/ha, 10.7~14.6cm, and 17.7~22.2$\m^2$/ha, respectively. With increasing elevation mean DBH and basal area of tree stratum increased while density of tree stratum decreased. As elevation increased the importance values of Quercus mongolioa, Styrax japonica, Acer pseudo-sieboldiannum, and Sorbus alnifolia increased while those of Pinus thunbergii, Pinus densiflora, Prunus sargentii, Cornus kousa, and Eurya japonica decreased. The importance values of Fraxinus sieboldiana, Quercus variabilis, and Sorbus alnifolia increased as going from lower part to upper part of the slope. However, the opposite trend was found for the importance values of Styrax japonica, Lindera erythrocarpa, and Zelkova serrata, With incresing elevation number of species, species diversity, and evenness incresed and it was suggested that man interference was relatively severe. The range of similarity indices between elevation belts and between parts of the slope were 42.0~71.8% and 74.8~76.8%, respectively. According to importance values and cluster analysis, the studied valley forest was classified into four forest communities of Quercus serrata-Pinus densiflora community in low elevation belt, Carpinus laxiflora-deciduous tree species community in high elevation belt and lower and middle parts at middle elevation belt, Quercus variabilis-Carpinus laxiflora community in upper part at middle elevation belt, and Quercus mongolica-Styrax japonica community in top area. There were significantly positive correlation among Quercus serrata, Pinus densiflora, Pinus thunbergii, and Eurya japonica and among Carpinus laxiflora, Zelkova serrata, and Cornus walteri.

• Journal of the Korean Society for Marine Environment & Energy
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• v.13 no.2
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• pp.112-120
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• 2010

In this paper time series wave data measured continuously for 24 hours during a storm in Yura Sea Area are used to investigate statistical characteristics of nonlinear waves. The exceedance probability of wave height is compared using the Rayleigh distribution and the Edgeworth-Rayleigh (ER) distribution. Wave data which show stationary state for 10 hours contain 4600 waves approximately. The Gram-Chalier distribution fits the probability of wave elevation better than the Gaussian distribution. The Rayleigh ($H_{rms}$) distribution follows the exceedance probability of wave height in general and predicts the probability of freak waves well. The ER distribution overpredicts the exceedance probability of wave heights and the occurrence of freak waves. If wave data measured for 30 minute period which contains 250 waves are used, the ER distribution can predict the occurrence probability of freak waves well. But it overpredicts the probability of overall wave height If no freak wave occurs, the Rayleigh ($H_{rms}$) distribution agrees well with wave height distribution for the most of wave height ranges. The wave height distribution of freak waves of which height are less than 10 m shows similar tendency compared with freak waves greater than 10 m. The value of $H_{max}/H_{1/3}$ is related to the kurtosis of wave elevation. It seems that there exists threshold value of the kurtosis for the occurrence of freak waves.

• Journal of the Korean Association of Geographic Information Studies
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• v.24 no.2
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• pp.52-63
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• 2021

In previous research, the coastal wetlands were detected by using the vegetation indices or land cover classification maps derived from the multispectral bands of the satellite or aerial imagery, and this approach caused the various limitations for detecting the coastal wetlands with high accuracy due to the difficulty of acquiring both land cover and topographic information by using the single remote sensing data. This research suggested the efficient methodology for detecting the coastal wetlands using the sentinel-2 satellite image and SRTM(Shuttle Radar Topography Mission) DEM (Digital Elevation Model) acquired in Gomsoman Bay, west coasts of South Korea through the following steps. First, the NDWI(Normalized Difference Water Index) image was generated using the green and near-infrared bands of the given Sentinel-2 satellite image. Then, the binary image that separating lands and waters was generated from the NDWI image based on the pixel intensity value 0.2 as the threshold and the other binary image that separating the upper sea level areas and the under sea level areas was generated from the SRTM DEM based on the pixel intensity value 0 as the threshold. Finally, the coastal wetland map was generated by overlaying analysis of these binary images. The generated coastal wetland map had the 94% overall accuracy. In addition, the other types of wetlands such as inland wetlands or mountain wetlands were not detected in the generated coastal wetland map, which means that the generated coastal wetland map can be used for the coastal wetland management tasks.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.20 no.6
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• pp.84-99
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• 2021

As the micro-mobility market grows, the demand for route guidance, that includes uphill information as well, is increasing. Since the climbing angle depends on the electric motor uesed, it is necessary to establish an uphill road DB according to the threshold standard. Although road alignment information is a very important element in the basic information of the roads, there is no information currently on the longitudinal slope in the road digital map. The High Definition(HD) map which is being built as a preparation for the era of autonomous vehicles has the altitude value, unlike the existing standard node link system. However, the HD map is very insufficient because it has the altitude value only for some sections of the road network. This paper, hence, intends to propose a method to generate the road longitudinal slope using currently available data. We developed a method of computing the longitudinal slope by combining the digital elevation model and the standard link system. After creating an altitude at the road link point divided by 4m based on the Seoul road network, we calculated individual slope per unit distance of the road. After designating a representative slope for each road link, we have extracted the very steep road that cannot be climbed with personal mobility and the slippery roads that cannot be used during heavy snowfall. We additionally described errors in the altitude values due to surrounding terrain and the issues related to the slope calculation method. In the future, we expect that the road longitudinal slope information will be used as basic data that can be used for various convergence analyses.