• The Journal of Engineering Geology
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• v.29 no.2
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• pp.85-97
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• 2019

It can be observed that steep slopes ($65^{\circ}$ to $80^{\circ}$) consist of rock masses were kept stable for a long time. In rock-mass slopes with similar ground condition, steeper slopes than 1 : 0.5 ($63^{\circ}$) may be applied if the discontinuities of rock-mass slope are distributed in a direction favorable to the stability of the slope. In making a decision the angle of the slope, if the preliminary rock mass conditions applicable to steep slope are quantitatively setup, they may be used as guidance in design practice. In this study, the above rock mass was defined as a good continuum rock mass and the quantitative setup criterion range was proposed using RMR, SMR and GSI classifications for the purpose of providing engineering standard for good continuum rock mass conditions. The methods of study are as follows. The stable slope at steep slopes ($65^{\circ}$ to $80^{\circ}$) for each rock type was selected as the study area, and RMR, SMR and GSI were classified to reflect the face mapping results. The results were reviewed by applying the calculated shear strength to the stable analysis of the current state of rock mass slope using the Hoek-Brown failure criterion. It is intended to verify the validity of the preliminary criterion as a rock mass condition that remains stable on a steep slope. Based on the analysis and review by the above research method, it was analyzed that a good continuum rock mass slope can be set to Basic RMR ${\geq}50$ (45 in sedimentary rock), GSI and SMR ${\geq}45$. The safety factor of the LEM is between Fs = 14.08 and 67.50 (average 32.9), and the displacement of the FEM is 0.13 to 0.64 mm (average 0.27 mm). This can be seen as a result of quantitative representation and verification of the stability of a good continuum rock mass slope that has been maintained stable for a long period of time with steep slopes ($65^{\circ}$ to $80^{\circ}$). The setup guideline for a good continuum rock mass slope will be able to establish a more detailed setup standard when the data are accumulated, and it is also a further study project. If stable even on steep slopes of 1 : 0.1 to 0.3, the upper limit of steep slopes is 1 : 0.3 with reference to the overseas design standards and report, thus giving the benefit of ensuring economic and eco-friendlyness. Also, the development of excavation technology and plantation technology and various eco-friendly slope design techniques will help overcome psychological anxiety and rapid weathering and relaxation due to steep slope construction.

• Journal of the Korean Society of Radiology
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• v.81 no.2
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• pp.365-378
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• 2020

Purpose This study was performed to determine whether the T1 relaxation time of gadoxetic acid-enhanced liver MR imaging is useful for detecting and staging liver fibrosis in patients with chronic liver disease. Materials and Methods One hundred and three patients with suspected focal liver lesion underwent MR imaging and Fibroscan. Fibroscan was chosen as the reference standard for classifying liver fibrosis. T1 relaxation times were acquired before (preT1), 20 minutes after (postT1) contrast administration, and reduction rate of T1 relaxation time (rrT1) on transverse 3D VIBE (volumetric interpolated breath-hold examination) sequence using 3T MR imaging. The optimal cut-off values for the fibrosis staging were determined with ROC analysis. Results PreT1 and postT1 increased and rrT1 decreased constantly with increasing severity of liver fibrosis according to the METAVIR score (F0-F4). There were statistically significant differences between F2 and F3 in preT1 (F2, 836.0 ± 74.7 ms; F3, 888.6 ± 77.5 ms, p < 0.05) and between F3 and F4 in postT1 (F3, 309.0 ± 80.2 ms; F4, 406.6 ± 147.7 ms, p < 0.05) and rrT1 (F3, 65.4 ± 7.7%; F4, 57.3 ± 11.4%, p < 0.05). ROC analysis revealed that combination test (preT1 + postT1) was the best test for predicting liver fibrosis. Conclusion PreT1 and postT1 increased constantly with increasing severity of liver fibrosis. T1 mapping in gadoxetic acid-enhanced liver MR imaging could be a helpful complementary sequence to determine the liver fibrosis stage.

• Journal of the Korean Association of Geographic Information Studies
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• v.9 no.4
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• pp.22-33
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• 2006

The objective of this paper is to discuss geographic information policies and strategies of British government and suggest effective policies for Korea National GIS project GIS that has been implemented geographic information infrastructures into public sectors and private markets for the last ten years. To obtain the research aim, this paper reviews the main factors of the Britain GIS project such as distribution structure and process of GI markets, government policies and strategies that are led by Ordnance Survey, most leading mapping agency in the UK. In conclusion, some issues have been explored with reference to the experiences of the Britain GIS projects. The first of these is the nature of geographic information and the second concerns the notion of the circulation policies of spatial data, and the last proposes Korea GIS policies and strategies for successful geographic information and spatial data implementation. The findings of the analysis of the Britain GIS development indicate that a shift began to take place from central government coordinate toward more extensive utilization of private and commercial sectors. This reflects both the increasing importance of geospatial data circulation in all levels of GIS stakeholders. Finally these discussions are particularly to be the issues where multi-agency collaboration of Korea government is concerned and can take the form of joint ventures by consortiums of both involving data producers and data users in order to increase commercial participation for value-added geospatial items, and to encourage both research and development sectors with low or free price policies.

• The Journal of Engineering Geology
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• v.25 no.1
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• pp.115-129
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• 2015

The cut-slope of a large-sectional tunnel portal is recognized as a potential area of weakness due to unstable stress distribution and possible permanent displacement. This paper presents a case study of a slope failure and remediation for a large-scale cut-slope at a tunnel portal. Extensive rock-slope brittle failure occurred along discontinuities in the rock mass after 46 mm of rainfall, which caused instability of the upper part of the cut-slope. Based on a geological survey and face mapping, the reason for failure is believed to be the presence of thin clay fill in discontinuities in the weathered rock mass and consequent saturationinduced joint weakening. The granite-gneiss rock mass has a high content of alkali-feldspar, indicating a vulnerability to weathering. Immediately before the slope failure, a sharp increase in displacement rate was indicated by settlement-time histories, and this observation can contribute to the safety management criteria for slope stability. In this case study, emergency remediation was performed to prevent further hazard and to facilitate reconstruction, and counterweight fill and concrete filling of voids were successfully applied. For ultimate remediation, the grid anchor-blocks were used for slope stabilization, and additional rock bolts and grouting were applied inside the tunnel. Limit-equilibrium slope stability analysis and analyses of strereographic projections confirmed the instability of the original slope and the effectiveness of reinforcing methods. After the application of reinforcing measures, instrumental monitoring indicated that the slope and the tunnel remained stable. This case study is expected to serve as a valuable reference for similar engineering cases of large-sectional slope stability.

• Journal of the Korean earth science society
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• v.32 no.6
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• pp.525-536
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• 2011

In any applications using various types of spatial data, it is very important to account for the scale differences among available data sets and to change the scale to the target one as well. In this paper, we propose to use a geostatistical downscaling approach based on vaiorgram deconvloution and block simulation to generate fine-scale categorical thematic maps from coarse-scale fraction data. First, an iterative variogram deconvolution method is applied to estimate a point-support variogram model from a block-support variogram model. Then, both a direct sequential simulation based on area-to-point kriging and the estimated point-support variogram are applied to produce alternative fine-scale fraction realizations. Finally, a maximum a posteriori decision rule is applied to generate the fine-scale categorical thematic maps. These analytical steps are illustrated through a case study of land-cover mapping only using the block fraction data of thematic classes without point data. Alternative fine-scale fraction maps by the downscaling method presented in this study reproduce the coarse-scale block fraction values. The final fine-scale land-cover realizations can reflect overall spatial patterns of the reference land-cover map, thus providing reasonable inputs for the impact assessment in change of support problems.

• Journal of Environmental Policy
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• v.8 no.2
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• pp.1-23
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• 2009

This study applied satellite radar imagery to identify flooded areas and examined post-flooding conditions using time-series satellite radar imagery for the development of flood damage mitigation strategies. Using time-series satellite radar images, this study constructed a map delineating areas vulnerable to frequent flood damage. The extracted flooded areas were combined with reference land use maps to examine flood damage by land use type. Major landuse types with severe flood damage were agricultural and forested areas. The analysis of the damage conditions, in terms of land use, served as the basis for developing flood damage mitigation policies, in conjunction with land use planning. The policies for flood damage mitigation can be summarized as land use regulations, land use planning, and flood damage mapping. A preventive measure to minimize flood damage of properties, which regulates developing areas with high flooding potential, is highly recommended. Although this study suggested a number of policies for flood damage mitigation, they represent only a small number of possible policies useful for mitigating flood damage and other environmental problems. Based upon the results of this study, it may be concluded that satellite radar imagery has great potential in providing basic data for large-scale environmental problems such as flooding and oil spills. Nevertheless, further examinations should be conducted and the application of satellite radar imagery should be used to examine other environmental problems.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.49 no.4
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• pp.15-25
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• 2012

The research on the FPGA CAD tools in academia has been lacking practicality due to the underlying FPGA fabric architecture which is too simple and inefficient to be applied for commercial FPGAs. Recently, the database of placement positions and routing graphs on commercial FPGA architectures has been built, and provided for enabling the academic development of placement and routing tools. To extend the limit of academic CAD tools even further, we have developed the evaluation toolkit for the K-FPGA architecture which is under development. By providing interface for exchanging data with a commercial FPGA toolkit at every step of mapping, packing, placement and routing in the tool chain, the toolkit enables individual tools to be developed without waiting for the results of the preceding step, and with no dependency on the quality of the results, and compared in detail with commercial tools at any step. Also, the fabric primitive library is developed by extracting the prototype from a reporting file of a commercial FPGA, restructuring it, and modeling the behavior of basic gates. This library can be used as the benchmarking target, and a reference design for new FPGA architectures. Since the architecture is described in a standard HDL which is familiar with hardware designers, and read in the tools rather than hard coded, the tools are "data-driven", and tolerable with the architectural changes due to the design space exploration. The experiments confirm that the developed library is correct, and the functional correctness of applications implemented on the FPGA fabric can be validated by simulation. The placement and routing tools are under development. The completion of the toolkit will enable the development of practical FPGA architectures which, in return, will synergically animate the research on optimization CAD tools.

• Genomics & Informatics
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• v.6 no.1
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• pp.18-28
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• 2008

Single nucleotide polymorphisms (SNPs) are the most abundant forms of human genetic variations and resources for mapping complex genetic traits and disease association studies. We have constructed a linkage disequilibrium (LD) map of chromosome 22 in Korean samples and compared it with those of other populations, including Yorubans in Ibadan, Nigeria (YRI), Centre d'Etude du Polymorphisme Humain (CEPH) reference families (CEU), Japanese in Tokyo (JPT) and Han Chinese in Beijing (CHB) in the HapMap database. We genotyped 4681 of 111,448 publicly available SNPs in 90 unrelated Koreans. Among genotyped SNPs, 4167 were polymorphic. Three hundred and five LD blocks were constructed to make up 18.6% (6.4 of 34.5 Mb) of chromosome 22 with 757 tagSNPs and 815 haplotypes (frequency $\geq$ 5.0%). Of 3430 common SNPs genotyped in all five populations, 514 were monomorphic in Koreans. The CHB + JPT samples have more than a 72% overlap with the monomorphic SNPs in Koreans, while the CEU + YRI samples have less than a 38% overlap. The patterns of hot spots and LD blocks were dispersed throughout chromosome 22, with some common blocks among populations, highly concordant between the three Asian samples. Analysis of the distribution of chimpanzee-derived allele frequency (DAF), a measure of genetic differentiation, Fst levels, and allele frequency difference (AFD) among Koreans and the HapMap samples showed a strong correlation between the Asians, while the CEU and YRI samples showed a very weak correlation with Korean samples. Relative distance as a quantitative measurement based upon DAF, Fst, and AFD indicated that all three Asian samples are very proximate, while CEU and YRI are significantly remote from the Asian samples. Comparative genome-wide LD studies provide useful information on the association studies of complex diseases.

• Journal of the Korean Society of Costume
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• v.20
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• pp.151-167
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• 1993

The purpose of this study is to systematize the theory of the Fashion Marketing and merchandi-sing system as well as the strategy for the Mar-keting based on the related variable. Furthermore, this study deals with development of the mark-eting strategy to the relation between consumers and industry. The content conclusion on the research can be outlined as follows : 1. In order to inverstigate how the life-style of consumers affects their sense of fashion, awa-reness of brand, and decision making process of purchase, the life-style of women consumers is classified into 15 types. (1) Acording to the different life-style types, and important difference is found in the consum-ers' sense of clothes, a unique image of outfit and its own favorite image of womanliness. (2) The consumer's awareness of a particular brand has a reasonable relationship with their brand preference and possession of the brands. (3) Their is an important discrimination acco-rding to the life-style types in their brand awar-eness and preference and possesion of brands. (4) The consumers of each life-style type show noticeable difference in the decision making pro-cess of purchase including he motive of purchase, the source of information, the cause of purchase intention, price, the frequency of purchase and the degree of satisfaction of purchased goods. 2. The merchandising system and the market positioning among the fashion industry are compared and analyzed in the following terms ; (1-1) For the purpose of establishing the target market strategy, the industry uses unreasenalbe methods to analyze the life-style of the target customers and the real customers(36%) and the aging phenomenon of brands is remarkable : as much as 37% of brands show over 5 years-old age gap. (1-2) The price setting process depends highly on the cost-plus approach. (1-3) In color planning, too many colors are used in every season(the average number is 22.3) and the investigation of the consumers' favorite color is neglected. (1-4) The manufacturers of successful brands are much likely to employ the textile designer and allow them to develop the various fabrication. (1-5) The regular rate of sales in each season is extremely low(56.04%) : the rate of the succ-essful brands is relatively high at 65%, but that of the unsuccessful as low as 51%. (1-6) 47% of brands reveal the designer-orie-nted fashion merchandising system. The successful brands, on the other hand, show a high rate of merchandiser oriented system. (2) Since the brand positioning is highly cen-tered on each brand image, styles and target age, the new data are presented in this study for the new market development. (3) To set up the target market, the mapping of images between the differentiated market and the consumers is suggersted according to the market positioning of industry and 15 types of the life-styles of consumers.

• Korean Journal of Agricultural and Forest Meteorology
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• v.10 no.1
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• pp.1-8
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• 2008

The concept of growing degree-days (GDD) is widely accepted as a tool to relate plant growth, development, and maturity to temperature. Information on GDD can be used to predict the yield and quality of several crops, flowering date of fruit trees, and insect activity related to agriculture and forestry. When GDD is expressed on a spatial basis, it helps identify the limits of geographical areas suitable for production of various crops and to evaluate areas agriculturally suitable for new or nonnative plants. The national digital climate maps (NDCM, the fine resolution, gridded climate data for climatological normal years) are not provided on a daily basis but on a monthly basis, prohibiting GDD calculation. We applied a widely used GDD estimation method based on monthly data to a part of the NDCM (for Hapcheon County) to produce the spatial GDD data for each month with three different base temperatures (0, 5, and $10^{\circ}C$). Synthetically generated daily temperatures from the NCDM were used to calculate GDD over the same area and the deviations were calculated for each month. The monthly-data based GDD was close to the reference GDD using daily data only for the case of base temperature $0^{\circ}C$. There was a consistent overestimation in GDD with other base temperatures. Hence, we estimated spatial GDD with base temperature $0^{\circ}C$ over the entire nation for the current (1971-2000, observed) and three future (2011-2040, 2041-2070, and 2071-2100, predicted) climatological normal years. Our estimation indicates that the annual GDD in Korea may increase by 38% in 2071-2100 compared with that in 1971-2000.