• Geophysics and Geophysical Exploration
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• v.21 no.4
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• pp.220-230
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• 2018

When thermal conductivity of rock is measured with PEDB (Portable Electronic Divided Bar) in a laboratory, it can be greatly influenced by the change of room temperature. Therefore, measuring the thermal conductivity in a thermo-hygrostat is necessary, where it can remain in its constant temperature and humidity condition. In this study, a system for thermal conductivity measurement in a thermo-hygrostat has been set up and the thermal conductivities for the 45 samples collected from GH3 and GH4 boreholes in Ulleung Island have been measured both in dry and saturated conditions. Also, the correlations between those thermal conductivities, density, and effective porosity have been discussed. As a result of correlation analysis among the thermal conductivity, density, and effective porosity, it showed higher correlation with dry samples than saturated samples. Especially, thermal conductivity ratio between saturated and dry conditions shows very high correlation ($R^2=0.90$) with effective porosity.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.1
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• pp.87-93
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• 1982

Dihaploid lines derived from the another of the $F_1$ of single cross, SC72 $\times$ Hicks (Nicotiana tabacum L.) were estimated the variation, heritablities, genetic correlations and path-co-efficients on agronomic characters and chemical compositions. Dinaploids exhibited reduced vigor and growth when comparecd with the mid-parent value but had increased nicotine contents, and the range of dihaploids characters were deviated more than that of their parents. Heritabilities of days to flowering, leaves per plant, nicotine. contents, leaf size and plant height appeared high value, and the yield, value per kg. and reducing sugar contents were low. There were positive genetic correlations between yield, and value per kg., leaf width, leaves per plant and reducing sugar contents and negative genetic correlations appeared between nicotine contents and the other characters except for index of leaf shape. Path-coefficient analysis of genotypic correlation coefficients showed that leaves per plant and leaf width lave a high direct effect, and plant height and days to flowering have a high indirect effect on yield, respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.spc1
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• pp.174-178
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• 2006

This study was conducted to compare the changes of isoflavone content grown at different planting dates and to determine a relationship between growing periods and isoflavone content, in soybean. A total fifty six soybean varieties, including summer type soybean, Chinese varieties and domestic soybean varieties, were used this experiment. Mean total isoflavone content of domestic soybean varieties was higher than summer type soybean varieties and Chinese varieties. And, the soybean isoflavone content was significantly increased in growth at late planting dates. Soybean isoflavone contents was increased with longer reproductive growth period. While, the relationship between seed weight and isoflavone content showed significantly negative correlation coefficient, -0.57 at Apr. 15, -0.51 at May 15, and -0.38 at Jun. 15, respectively planting dates.

• Korean Journal of Environment and Ecology
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• v.25 no.1
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• pp.65-70
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• 2011

The fish fauna and population of Zacco koreanus in the upper region of the Gapyeong Stream was investigation from April, 2005 to August, 2009. The collected species during the survey period were 16 species belonging to 6 families. Dominant species was Z. koreanus and subdominant species was Pungtungia herzi. korea endemic species were Pseudopungtungia tenuicorpa, Coreoleuciscus splendidus, Hemibarbus mylodon, Gobiobotia brevibarba, Microphysogobio longidorsalls, Z. koreanus, Koreocobitis rotundicaudata, Iksookimia koreensis, Silorus microdorsalis, Liobagrus andersoni, Coreoperca herzi and Odontobutis platycephala, which showed a ratio of 75 % in all collected species. The species of H. mylodon was identified as natural monument, and P. tenuicorpa and G. brevibarba were endangered species. Length-weight relationship in the population of Z. koreanus was 3.44, and condition factor in the popuation was 0.004. The spawning season of Zacco koreanus was May and June.

• Journal of Korean Society of Steel Construction
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• v.12 no.3 s.46
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• pp.239-250
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• 2000

This study investigates the mechanical behavior on trough rib to crossbeam joint in orthotropic steel plate decks, specially emphasizing on the effect of diaphragm inside trough rib on the fatigue behavior of slit by static and fatigue tests. In particular, the effects of diaphragm on in-plane stress and out-of-plane stress, stress concentration, propagation of fatigue cracks at the silt are studied. With the result of experiment and numerical analysis, we have estimated the fatigue strength using the nominal stress and hot-sport stress. The details with diaphragm have occurred about 50% stress reduction at trough rib part of trough rib to crossbeam joint than the detail without diaphragm, however, the lower parts of crossbeam have occurred much more stress. Initial crack size or slit have an considerable influence on the propagation of fatigue cracks due to V-notch. The fatigue strength category of the details without diaphragm has higher value than fatigue limit, whereas that of the details with diaphragm is estimated lower than fatigue limit.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.4
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• pp.477-482
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• 1986

This trial was carried out to set up a proper drum speed of thresher to minimize the mechanical damage from threshing and thereby to obtain rye seeds possessing higher qualities for seeds. Rye plants were harvested at from 40 to 60 days after heading (DAH) with 5 days intervals and spread out on the field for 0, I, 2, 3 days for drying, respectively. After drying the plants were subjected to threshing at seven steps of drum speed from 400 to 1000 rotation per minute (RPM) of a thresher, drum diam. 18.6cm, teeth length 6cm. At 500 to 600 RPM and from the plants harvested at 55DAH with drying for one or two days, the seeds possessed low grain damage, high germinability over 90%, and field emergence rate over 80%.

• Korean Journal of Environmental Agriculture
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• v.24 no.2
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• pp.139-145
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• 2005

All 209 PCB congeners were analyzed in cheese produced in Korea and Canada. 5 Korean and 10 Canadian cheeses were purchased in supermarket in their native countries. 93 PCB congeners were found in Korean cheese; 83 congeners were detected in Canadian cheese. Total PCB concentrations were 299.81 and 200.96 pg/g w.w. in Korean and Canadian cheeses respectively; PCB concentration was 1.5 times higher in Korean than Canadian cheese. Korean TEQ concentration (0.0067 pg-TEQ/g w.w.) in cheese was similar to in Canadian cheese (0.0064 pg-TEQ/g w.w.). These PCB concentrations range was low level compared with that of other cheeses globally. The correlation coefficient $(R^2)$ of regression was high (0.752) between each PCB congener concentration in both Korean and Canadian cheese.

• FLOWER RESEARCH JOURNAL
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• v.16 no.1
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• pp.76-84
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• 2008

This study was conducted to find out the cause of discoloration after pressing yellow-colored flowers. Plant materials used were Lilium Asiatic Hybrids, Oncidium spp., Rosa hybrida, $Tulipa{\times}gesneriana$, Antirrhinum majus, Dianthus caryophyllus, Freesia hybrida, Zantedeschia elliottiana, Gerbera jamesonii, Helianthus annuus, and Ranunculus asiaticus. Thickness, ratio of length to width, and water content of petals did not considerably affect discoloration of pressed flowers. Expression of yellow color in petals was caused by carotenoids in Lilium Asiatic Hybrids, Oncidium spp., Rosa hybrida and $Tulipa{\times}gesneriana$, by flavonoids in Antirrhinum majus, Dianthus caryophyllus, Freesia hybrida and Zantedeschia elliottiana, and by coexistence of carotenoids and flavonoids in Gerbera jamesonii, Helianthus annuus and Ranunculus asiaticus. Carotenoids that expressed yellow color in petals affected significantly on discoloration in pressed flowers containing carotenoids alone or both carotenoids and flavonoids. However, discoloration was hardly ever found in yellow-colored species as affected by flavonoids. Dark treatment was effective for almost perfect preservation in color of pressed flowers, while light treatment resulted in severe discoloration.

• Journal of Wetlands Research
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• v.24 no.4
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• pp.312-319
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• 2022

The species diversity of plant communities is quantitatively measured, and can be affected by plant monitoring methods. This study experimentally compared the structure and diversity of plant communities living in five waterfront park areas in Nak-dong River using three plant survey methods (modified Whittaker, modified Daubenmire, and modified point-line intercept method). According to the diversity profile, the modified Whittaker method produced the highest species richness regardless of the location, but which method makes the highest diversity of dominant species varies depending on the location. The Beta diversity of the communites calculated from the modified Whittaker and the modified Daubenmire suggested that structures of plant communities in five locations were similar, while the Point-line interception method suggested that a small number of dominant species were shared between communities.

• Korean Journal of Environmental Agriculture
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• v.22 no.2
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• pp.100-110
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• 2003

This study was conducted to evaluate influence of chemical properties in the riparian on the species diversity and to get plant information for enhancement of natural purification in Mankyeong River. The concentration of total nitrogen was high in Jeonju and Sam stream, while that of total nitrogen showed the highest peak in Winter. Concentrations of $NH_4-N$ was $0.01{\sim}0.06\;mg/L$ in Gosan and Soyang stream. The water quality of upstream along with Mankyeong River was suitable for the irrigation source. The riparian vegetation was investigated by Zurich-Montpellier school's method from June, 2001 to September, 2002. The number of riparian plants were 59 families, 129 genera, 165 species, 20 varieties in Gosancheon, on the while 53 families, 111 genera, 141 species, 19 varieties in Soyangcheon. The number of riparian plants in Bari basin was higher than that of other sites namely, 73 families, 134 genera, 218 species, 33 varieties. Riparian vegetation was consisted of 12 plant communities. The contents of organic matter, total nitrogen and electrical conductivity had negative relationship with species diversity (Species richness index, Heterogeneity index, Species evenness index Species number). On the while, species diversity had positive relationship with soil pH. Species diversify of the plant communities were affected by topography and disturbance.