• The Journal of Engineering Geology
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• v.25 no.3
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• pp.349-356
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• 2015

Although geophysical methods are useful and generally provide valuable information about the subsurface, it is important to recognize their limitations. A common limitation is the lack of sufficient contrast in physical properties between different layers. Thus, multiple methods are commonly used to best constrain the physical properties of different layers and interpret each section individually. Ground penetrating radar (GPR) and shallow seismic reflection (SSR) methods, used for shallow and very shallow subsurface imaging, respond to dielectric and velocity contrasts between layers, respectively. In this study, we merged GPR and SSR data from a test site within the Cheongui granitic mass, where the water table is ~3 m deep all year. We interpreted the data in combination with field observations and existing data from drill cores and well logs. GPR and SSR reflections from the tops of the sand layer, water table, and weathered and soft rocks are successfully mapped in a single section, and they correlate well with electrical resistivity data and SPS (suspension PS) well-logging profiles. In addition, subsurface interfaces in the integrated section correlate well with S-wave velocity structures from multi-channel analysis shear wave (MASW) data, a method that was recently developed to enhance lateral resolution on the basis of CMP (common midpoint) cross-correlation (CMPCC) analysis.

• Korean Journal of Environmental Agriculture
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• v.1 no.1
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• pp.31-38
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• 1982

The water quality at the Nakdong River stream was surveyed for 3 years from 1978 to 1980 at quarterly intervals of January, April, June and October at 12 sites along the main stream from Sangju to Imhaejin and at 2 sites of Geumho and Nam River tributaries. The overall results are summarized as follows: 1) The levels of dissolved oxygen in the Geumho River tributary on the basis of three-year average were 0.7 ppm in January, 1.3 ppm in April, 4.0 ppm in July and 0.8 ppm in October. BOD concentrations in the same period were 91 ppm in January, 37 ppm in April, 6 ppm in July and 24 ppm in October. The water of Geumho River was so highly contaminated that the water seems to be unsuitable for any type of water use. 2) The relatively clean water in the upstream of the main Nakdong River was rapidly polluted by the highly contaminated water of Geumho tributary. That is, dissolved oxygen and BOD at Hwawon site right after junction of the tributary were 10.4, 8.8 ppm in January, 5.8, 6.5 ppm in April, 6.3, 3.2 ppm in July and 7.0, 5.3 ppm in October, respectively. The values of turbidity, ammoniacal nitrogen and electrical conductivity were also observed to be quite high.

• Korean Journal of Ecology and Environment
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• v.43 no.1
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• pp.11-18
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• 2010

The contamination of a suite of heavy metals were evaluated in water and sediments of urban stream, Tancheon down the stream. Tancheon is a urban stream which goes all the way across the urban area where various pollution sources are present. The sixteen study sites from seven different areas were designated down the stream. The heavy metal levels of the streams were detected in the order of Zn>Cu>Ni>Pb>Cd>Cr>Sb. There was a difference in the relative order of the concentration ranking in lake sediments. There is a trend that the heavy metal levels are higher at the sites where the construction causes inflow of soil particles to stream. Toxicity tests using pore-water in sediments were conducted for samples collected in some study sites, and pore-water in one site was proven to be toxic to Japanes medaka (Oryzias latipes). The reason may be the fecal pollution rather than heavy metal effect. Strong odor was detected in the sediment whose pore-water samples showed ecotoxicity. We did not observed the increasing concentration of heavy metals down to stream since the soil texture varied in the stream area of our study. Further study is needed to find quantitative relations between the level of contamination and its eco-effect.

• Journal of Korean Society of Forest Science
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• v.102 no.1
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• pp.113-121
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• 2013

It has been known that edges of forest fire areas play significant roles in post-fire change of forest ecosystem and recovery process. The purpose of this study was to analyze the relationships between edge formation of burned forests and landscape characteristics with consideration on spatial autocorrelation. Samcheok fire site burned in 2000 was selected as the study area. Seven hundred fifty three of 500 $m^2$ grid cells were generated for measuring landscape characteristics. This study used the topographic variables including slop, elevation, topographic wetness index, solar radiation index and proportions of fuel and land use types. In delineating landscape characteristics correlation analysis with modified t-test were performed for exploring the relationships between edge formation and landscape characteristics. The results indicated that edge formation of burned forests was positively correlated with most variables including TWI, SRI, water, paddy, developed, farm, grass, bare soil, and negatively related with elevation, slope and all fuel types. Especially TWI (r=0.437) showed a strong positive correlation with edge formation. According to the results, edge of burned forests were likely formed when proportions of heterogeneous land use types were high with mild slope and low elevation.

• Journal of the Korean GEO-environmental Society
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• v.14 no.7
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• pp.39-50
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• 2013

Crib wall is one of the segmental grid retaining walls using headers and stretchers to establish the framework of the wall. In this method, grids formed by the intersection of headers and stretchers are generally filled with the gravel to maintain the weight of the wall. Therefore, the construction can be carried out with higher speed and much economically when compared with the concrete retaining wall. Furthermore, it has high drain capacity, and environmentally friendly aspects also have been pointed out because the possibility of the planting at the front of the wall. However, in the wooden crib wall method, the relative movement between the individual headers and stretchers was generally recognized, and stress redistribution in the gravel filling was also observed when subjected to the external loading and self-weight of filling. In this study, it was analyzed fracture types and causes of wooden crib wall through detailed investigation and analysis of a large crib wall construction site. As a results, it occurred the damage in the members of 5.7% in a total of 2,315 locations and the damage of header occurred in the members of a header 80.2%. The 65.7% of the damaged header are concentrated in the lower part of crib wall. Therefore, it was analyzed the differences of fracture types and causes of wooden crib wall depending on the installation position and the kinds of members. It is considered basically the members of various forms of distortion and the grain affecting.

• Journal of the Korean GEO-environmental Society
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• v.17 no.12
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• pp.27-34
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• 2016

Many steepened slopes have become increasingly advantageous because of the desire to increase land usage and decrease site development costs. The proven concept of tensile reinforcement allows construction of slopes with far steeper face angles than the soils natural angle. Steepened slope face reinforced with improved soil can increase land usage substantially while providing a natural appearance. The paper presents composite reinforced earth with improved soil surface and geogrid-reinforced backfill. For the stability of the steepened slope, the behavior of the composite reinforced earth are validated and verified by case study and numerical analysis. The case study has performed to investigate the deformation of reinforce soil slope for 14 months. Its horizontal behavior by general vertical load shows within the safe range (0.5% of structure height). As a result of numerical analysis and case study, the reinforcement effect of the steepened slope technique using improved soil is sufficient to be constructed as reinforced soil slope.

• Journal of Korean Medicine Rehabilitation
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• v.23 no.2
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• pp.105-115
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• 2013

Objectives : This study was aimed to review the trend of occupational health in korean medicine and to suggest the strategic approach. Methods : We collected 40 articles on occupational health in the internet site OASIS using the keyword 'workplace', 'worker'. Then we analyzed them. Results : There were 40 papers that were published between 2000 and 2012. Published papers on the korean journal of oriental preventive medicine were more than the other journals. Affiliation of the first author of the published papers was concentrated to one. Clinical research papers accounted for 90% of the total study. Papers on health management were more than half. Conclusions : Related to occupational health, high quality and large amount of research and development is needed and the active policy of the government should be supported in Korean medicine.

• The Journal of the Petrological Society of Korea
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• v.21 no.4
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• pp.397-403
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• 2012

Fe-REE deposits occurred in Jaeunri, Hongcheon formed by carbonatitic melts consist of 3 parts such as northern, middle and southern ore bodies showing discontinuous distribution, and extension shape of ore bodies can be figured through field survey and geometric analysis. Foliations in gneiss around northern and middle ore bodies represent NNE, whereas toward south its direction changes gradually from NE to ENE and finally N-S direction appears in southern ore body. From Jaeungyo to Saemaeulgyo geometric analysis from field work gives that fold shape in this area is open synclinal fold concavely and gently to NW with $45^{\circ}$ northwestward plunging axis, in contrast small scale anticline with $45^{\circ}$ northwestward plunging axis in Yagsooteo area near western part of Saemaeulgyo. Dragging effect could be occurred on these folds by WNW trending dextral strike-slip fault from Yagsooteo to Saemaeulgyo. New ore body can be confirmed from folding structure estimated by trend of foliation, and thus unidentified ore body may be exist under alluvial surface from middle to southern ore body and its distribution could show reversed "ㄱ", one of Korean consonants, considering with estimated strike and dip of foliations. This estimated extension of ore body figured out by structural analysis in the studied area works an important role for measuring of ore reserve and selecting of drilling site to find new ore body.

• Journal of Life Science
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• v.27 no.4
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• pp.398-407
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• 2017

BTG 1 (B-cell translocation gene 1) gene was first identified as a translocation gene in a case of B-cell chronic lympocytic leukemia. BTG1 is a member of the BTG/TOB family with sharing a conserved N-terminal region, which shows anti-proliferation properties and is able to stimulate cell differentiation. In this study, we identified and characterized the pacific oyster Crassostrea gigas BTG1 (cg-BTG1) gene from the gill cDNA library by an Expressed Sequence Tag (EST) analysis and its nucleotide sequence was determined. The cg-BTG1 gene encodes a predicted protein of 182 amino acids with 57% 56% identities to its zebrafish and human counterparts, and is an intron-less gene, which was confirmed by PCR analysis of genomic DNA. Maximal homologies were shown in conserved Box A and B. The deduced amino acid sequence shares high identity with other BTG1 genes of human, rat, mouse and zebrafish. The phylogenic analysis and sequence comparison of cg-BTG1 with other BTG1 were found to be closely related to the BTG1 gene structure. In addition, the predicted promoter region and the different transcription-factor binding site like an activator protein-1 (AP-1) response element involved in negative regulation and serum response element (SRE) were able to be identified by the genomic DNA walking experiment. The quantitative real-time PCR analysis showed that the mRNA of cg-BTG1 gene was expressed in gill, heart, digestive gland, intestine, stomach and mantle. The cg-BTG1 gene was expressed mainly in heart and mantle.

• Molecules and Cells
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• v.38 no.11
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• pp.950-958
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• 2015

BCS1L gene encodes mitochondrial protein and is a member of conserved AAA protein family. This gene is involved in the incorporation of Rieske FeS and Qcr10p into complex III of respiratory chain. In our previous study, AluYRa2-derived alternative transcript in rhesus monkey genome was identified. However, this transcript has not been reported in human genome. In present study, we conducted evolutionary analysis of AluYRa2-exonized transcript with various primate genomic DNAs and cDNAs from humans, rhesus monkeys, and crabeating monkeys. Remarkably, our results show that AluYRa2 element has only been integrated into genomes of Macaca species. This Macaca lineage-specific integration of AluYRa2 element led to exonization event in the first intron region of BCS1L gene by producing a conserved 3' splice site. Intriguingly, in rhesus and crabeating monkeys, more diverse transcript variants by alternative splicing (AS) events, including exon skipping and different 5' splice sites from humans, were identified. Alignment of amino acid sequences revealed that AluYRa2-exonized transcript has short N-terminal peptides. Therefore, AS events play a major role in the generation of various transcripts and proteins during primate evolution. In particular, lineage-specific integration of Alu elements and species-specific Alu-derived exonization events could be important sources of gene diversification in primates.