• Water Engineering Research
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• v.1 no.1
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• pp.11-23
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• 2000

Regional flood frequency analysis has been developed by employing the nearby site's information to improve a precision in estimating flood quantiles at the site of interest. In this paper, single site and regional flood frequency analyses were compared based of the 2-parameter Weibull model. For regional analysis, two approaches were employed. The First one is to use the asymptotic variances of the quantile estimators derived based of the assumption that all sites including the site of interest are independent each other. This approach may give the maximum regional gain due to the spatial independence assumption among sites. The second one in Hosking's regional L-moment algorithm. These methods were applied to annual flood data. As the results, both methods generally showed the regional gain at the site of interest depending on grouping the sites as homogeneous. And asymptotic formula generally shows smaller variance than those from Hosking's algorithm. If the shape parameter of the site of interest from single site analysis is quite different from that from regional analysis then Hosking's results might be better than the asymptotic ones because the formula was derived based on the assumption that all sites have the same regional shape parameter. Furthermore, in such a case, regional analysis might be worse than single site analysis in the sense of precision of flood quantile estimation. Even though the selected sites may satisfy Hosking's criteria, regional analysis may not give a regional gain for specific and nonexceedance probabilities.

• Journal of Soil and Groundwater Environment
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• v.21 no.6
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• pp.1-13
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• 2016

The programmable logic array to match the treatment technology to the soil contaminated site based on the site properties in Korea was developed. Based on the previous technology screening system of FRTR (Federal Remediation Technology Roundtable) in USA, total 9 evaluation factors indicating the site characteristics were used for the technology matching process and 8 factors among them were quantitatively weighed in the order of importance. The class interval for each evaluation factor was linearly distributed to give the weighed score and 8 scores were summed up to prioritize the treatment technology. The optimal treatment technology for a specific site was determined according to the total score acquired from 8 evaluation factors used in this technology matching process. The reliability test for the developed technology matching system was done by using information of two real cleanup sites in Korea, suggesting that this guideline will be available to determine the most effective treatment technology to cleanup the soil contaminated site and also to assist the government or the company to design a successful and cost-effective site cleanup plan in Korea.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2001.09a
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• pp.19-27
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• 2001

Seismic parameters fur computation of ground motions in Southern Korea are obtained from recently recorded data, and site-independent regional and site-dependent local strong ground motions are predicted using efficient computational techniques. For the computation of ground motions, we devised an efficient procedure to compute site-independent $x_{q}$ and dependent $x_{s}$ values separately. The first step of this procedure is to use the coda normalization method far computation of site independent Q or corresponding $x_{q}$ value. The next step is the computation of $x_{s}$, values fur each site separately using the given $x_{q}$ value. For computation of ground motions the empirical Green's function (EGF) is modified to account fur the depth and distance variations of subevents on a finite fault plane using the theoritical Green's function. It is computed using wavenumber integration technique in layered media. The site dependent ground motions at seismic stations in southeastern local area were properly simulated using the modified empirical Green's function method in layered medium. The proposed method and procedures fur estimation of site dependent seismic parameters and ground motions could be efficiently used in the low and moderate seismicity regions.ons.s.ons.

• Journal of Soil and Groundwater Environment
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• v.25 no.2_spc
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• pp.70-85
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• 2020

This paper introduces the 'Smart Scoping for Environmental Investigations Technical Guide' issued by the US Environmental Protection Agency in 2018, which describes the use of smart scoping during lifecycle of remedial investigation projects. This paper also briefly summarizes the guidelines of soil and groundwater contamination investigation of South Korea. The smart scoping practices can support the development of a robust and realistic conceptual site model that is very useful for investigations and evaluations of the contaminated site. The application of evaluation tools relevant for the site-specific characteristics is important for the development of a conceptual site model. The smart scoping recommends the use of previous investigation data and implementation of best proven strategies for successful remedial investigation project. The use of smart scoping in contaminated site investigation will provide better management of contaminated sites.

• Journal of the Earthquake Engineering Society of Korea
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• v.20 no.4
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• pp.235-243
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• 2016

Korea is part of a region of low to moderate seismicity located inside the Eurasian plate with bedrock located at depths less than 30 m. However, the spectral acceleration obtained from site response analyses based on the geologic conditions of inland areas of the Korean peninsula are significantly different from the current Korean seismic code. Therefore, suitable site classification scheme and design response spectra based on local site conditions in the Korean peninsula are required to produce reliable estimates of earthquake ground motion. In this study, site-specific response analyses were performed at more than 300 sites with at least 100 sites at each site categories of $S_C$, $S_D$, and $S_E$ as defined in the current seismic code in Korea. The process of creating a huge database of input parameters - such as shear wave velocity profiles, normalized shear modulus reduction curves, damping curves, and input earthquake motions - for site response analyses were described. The response spectra and site coefficients obtained from site response analyses were compared with those proposed for the site categories in the current code. Problems with the current seismic design code were subsequently discussed, and the development and verifications of new site classification system and corresponding design response spectra are detailed in companion papers (II-development of new site categories and design response spectra and III-Verifications)

• Journal of the Korean Solar Energy Society
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• v.30 no.4
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• pp.86-91
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• 2010

The characteristics of hydrologic design parameters for small hydro power(SHP) sites located in four major river systems have been studied. The model, which can predict flow duration characteristic of stream, was developed to analyze the variation of inflow. And another model to predict hydrologic performance for SHP plants is established. The results from hydrologic performance analysis for SHP sites located on five major river systems based on the models developed in this study show that the specific design flowrate and specific output of SHP site have large difference between the river systems. The load factor, however, have small difference compared with specific design flowrate and specific output for all river systems. Also, it was found that the models developed in this study can be used to predict the primary design specifications of SSHP plants effectively.

• Journal of Soil and Groundwater Environment
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• v.16 no.6
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• pp.66-78
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• 2011

It is getting difficult to manage water resources in South Korea because more than half of annual precipitation is concentrated in the summer season and its intensity is increasing due to global warming and climate change. Artificial recharge schemes such as well recharge of surface water and roof-top rainwater harvesting can be a useful method to manage water resources in Korea. In this study, potential artificial recharge site is evaluated using geographic information system with hydrogeological and social factors. The hydrogeological factors include annual precipitation, geological classification based on geological map, specific capacity and depth to water level of national groundwater monitoring wells. These factors were selected to evaluate potential artificial recharge site because annual precipitation is closely related to source water availability for artificial recharge, geological features and specific capacity are related to injection capacity and depth to water is related to storage capacity of the subsurface medium. In addition to those hydrogeological factors, social aspect was taken into consideration by selecting the areas that is not serviced by national water works and have been suffered from drought. These factors are graded into five rates and integrated together in the GIS system resulting in spatial distribution of artificial recharge potential. Cheongsong, Yeongdeok in Gyeongsangbuk-do and Hadong in Gyeongsangnam-do, and Suncheon in Jeollanam-do were proven as favorable areas for applying artificial recharge schemes. Although the potential map for artificial recharge in South Korea developed in this study need to be improved by using other scientific factors such as evaporation and topographical features, and other social factors such as water-curtain cultivation area, hot spring resorts and industrial area where groundwater level is severely lowered, it can be used in a rough site-selection, preliminary and/or feasibility study for artificial recharge.

• Journal of Life Science
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• v.22 no.9
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• pp.1201-1206
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• 2012

The Crlz1 gene is known to be expressed specifically in the pre-B cell stage during B-cell development. With regards to the specific expression of the pre-B cell stage of the Crlz1 gene, we have previously identified three pre-B cell-specific DNase I hypersensitive sites (HSS), which are named HSS8, 9, and 10, in the upstream vicinity of this gene. In this paper, we report that HSS8 increases further the strong Crlz1 promoter activity driven by HSS9/10 and, therefore, acts as its enhancer. Furthermore, HSS8 has been finely mapped between -1055 and -1159 from the transcription start site of the Crlz1 gene.

• Korean Journal of Cognitive Science
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• v.11 no.1
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• pp.33-45
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• 2000

The present study examined the usability of the web site design, focusing on the cognitive characteristics of the WWW. Specifically, we conducted two major non-experimental usability testing methods on the domestic web sites with various purposes. In research I. we used an on-line questionnaire method on 12 domestic web sites. As a result. several critical usability features and factors were identified. In research 2. we carried out a heuristic evaluation method to identify more specific usability problems The result of research 2 suggests that the heuristic evaluation method reveals more specific problems of the web site design than the questionnaire method.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.9 no.3
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• pp.59-75
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• 2006

The vascular plants of this site was listed 360 taxa; 86 families, 229 genera, 311 species, 42 varieties and 7 forms. Specific plant species by floral region were total 40 taxa; 2 taxa(Crypsinus hastatus, Prunus yedoensis) in class V, Patrinia rupestris in class IV, 6 taxa(Elymus mollis, Carex laticeps, Poncirus trifoliata, Melia azedarach var. japonica, Koelreuteria paniculata, Crepiastrum lanceolatum) in class III, Cirsium schantarense in class II, 30 taxa(Lygodium japonicum, Pteris multifida, Phacelurus latifolius, Asparagus cochinchinensis, Ficus erecta, Machilus thunbergii, Zanthoxylum planispinum, Euphorbia esula, Mallotus japonicus, Cayratia japonica, Camellia japonica, Glehnia littoralis, Lysimachia fortunei, Messerschmidia sibirica, Ixeris repens etc.) in class I. The naturalized plants in this site were 14 families, 34 genera, 41 species, 1 varieties, 42 taxa and naturalization rate was 20.3% of all 207 taxa vascular plants. Based on the list of the rare plants by the Forest Research Institute, 2 taxa were recorded in the studied areas; Phacelurus latifolius, Crypsinus hastatus and based on the list of Korean endemic plants, 7 taxa were recorded; Populus tomentiglandulosa, Filipendula glaberrima, Prunus yedoensis, Forsythia koreana, Paulownia coreana, Weigela subsessilis, Carpinus coreana. So, wild plants disturbing ecosystem like Solanum carolinense and Ambrosia artemisiifolia var. elatior have been increasing, it needs continuing control and conservation measures on the plant ecosystem.