• Korean Journal of Materials Research
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• v.7 no.1
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• pp.50-56
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• 1997

급냉응고법을 이용하여 고용한도 이상으로 Mn량을 첨가할 때 Mn량에 따른 인장특성의 변화와 시효특성을 조사하였다. 원심분무법으로 AI-4.7%Zn-2.5%Mg-0.2%Zr합금에 Mn량을 각기 달리 첨가한 급냉응고 분말을 제조 하였다. 이 분말을 냉간압축, 진공 탈가스처리를 한 후 15:1로 압출하여 봉상 시편을 만들었다. 분말의 미세조직은 $\alpha$-AI수지상과 수지상간 편석부로 이루어져 있으며 Mn첨가에 따라 조직의 변화는 관찰되지 않았다. 빠른 냉각속도로 인하여 2.0%Mn을 첨가한 경우에도 초정 Mn상을 발견할 수 없었다. 압출재의 미세조직은 아결정립으로 이루어져 있으며 약간의 제2상들이 관찰되었다. 대부분의 Mn 분산상은 압출후 용체화처리 과정에서 형성되었으며 시효경화량은 Mn양에 관계없이 일정하였다. 46$0^{\circ}C$에서 1시간 용체화처리하고 12$0^{\circ}C$에서 24시간 시효처리한 경우 최대의 시효경도값을 나타내었다. 인장강도는 Mn첨가량에 따라 증가 하였는데 이것은 Mn분산상의 밀도증가에 의한 것으로 확인되었다. 2.0%Mn을 첨가한 합금의 시효후 인장강도는 590MPa, 연산율은 4%를 보였다.

• Korean Journal of Medicinal Crop Science
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• v.3 no.1
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• pp.5-8
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• 1995

This experiment was carried out to obtain the basic information on cultivation of Gentiana scabra BUNGE. Optimum temperature for germination, planting time effect of chemicals on rooting for cutting propagation, effect of cutting on root yield, and content of gentiopicroside were investigated. The germination ratio was highest at $25^{\circ}C$ but lower at $10,\;15,\;20\;,30^{\circ}C.$ The optimum planting time was March 20 the cutting in May and NAA treatment were effective on rooting for cutting propagation. Inhibition of flowering by cutting was effective for increasing root yield but not effective for gentiopicroside content of root.

• Journal of the Mineralogical Society of Korea
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• v.21 no.4
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• pp.373-382
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• 2008

First reported geochemical characteristics of mantle xneoliths (spinel peridotites) from Sunheul-ri, Jeju Island, provide important clues for understanding the lithosphere composition, equilibrium temperature, and the period of entrainment and transport of the xenoliths in the host magma. Core and rim of mineral phases in the xenoliths are constant chemical compositions as $Fo_{89-90}$ of olivines. The ranges of equilibrium temperature, obtained by two pyroxenes geothermometer, are about $951{\sim}1035^{\circ}C$ for Sunheul-ri spinel peridotite xenoliths and are similar to the range of equilibrium temperatures for the xenoliths from other sites in Jeju island. The period of entrainment and transport of the xenoliths in the host magma of Sunheul-ri mantle xenoliths is about 42 days.

• Korean journal of applied entomology
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• v.21 no.2 s.51
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• pp.95-98
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• 1982

The insecticides salithion$(Salithion^{(R)},\;25\;EC)$, decamethrin$(Decis^{(R)}\;1\;EC)$, phenthoate$(Elsan^{(R)},\;47.5\;EC)$, diazinon$(Diaton^{(R)})$, chlorfevinphes$(Birlane^{(R)},\;24\;EC)$, phosalone$(Zolone^{(R)},\;25\;EC)$, and methamidophos$(Tamaron^{(R)},\;60\;SL)$ were evaluated on the effectiveness of single ULV foliar spray for the control of the pine fall midges(Therodiplosis japonensis UCHIDA et INOUYE) when the insecticides diluted with the 50 times of water were applied to the pine trees$(1.5\~2m\;in\;height)$ on June 6 by ULV Sprayer(Battery-type of 12 voltage, devised by Union Carbide). A single ULV foliar spray of salithion, decamethrin, and phethoate among the insecticides tested was significantly effective for the pressure of the gall incidence by the insects.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.3 no.2
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• pp.167-175
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• 1993

Lithium-Carbon Intercalation Compounds(Li-CICs) have been synthesized from various carbon ma-terials by use of the modified stainless steel two-bulbs methods. These compounds had various colours by structural character of starting materials. The synthesized Li-CICs were identified to stage formation process by X-ray diffraction data. At these results, well-oriented natural graphite and graphite fiber are formed lower stages(Stage 1, Stage 2), but poor-oriented carbon fiber and petroleum cokes are also formed higher stages(Stage 3, Stage 4, Stage 5). And when we compared with measured d value and calculated d value, these values agreed with each other. But poor-oriented carbon materials are some difference from them. The stage stability and energy stage of Li-CICs were obtained by UV/VIS Spectrophotometric data. X-ray diffraction and UV/VIS Spectrophotometric data suggested that well-oriented carbon materials has distingushible curve between energy and reflectance. In these results, we know that many charge carriers between carbon layers are related to concentration of intercalants. And then, this paper also provides information on high efficiency energy storing materials at intercalation process of Li-CICs.

• Journal of Korean Clinical Health Science
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• v.4 no.4
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• pp.742-755
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• 2016

Pupose. This study aimed to analyze the relationship between metabolic syndrome and glaucoma in a middle-aged men over the age of 40's by using the data from the 5th Korean National Health and Nutrition Examination Survey(2010~2012). Methods. The subjects for the analysis were comprised of 410 patients who were at least 40 years or more with metabolic syndrome and glaucoma. The comparison between the metabolic syndrome and glaucoma according to the health demographic characteristics, health behavior and health conditions was analyzed with ${\chi}^2$-test. The complex samples logistic regression analysis was used to calculate the odds ratio of glaucoma according to the health demographic characteristics, health behavior and health conditions and the combination of the comprising factors of the metabolic syndrome. Results. The prevalence of glaucoma among the subjects with metabolic syndrome and glaucoma was significantly higher in the case of females, as their age increased, educational level decreased, income level decreased, who are non-smokers, non-drinkers, with exercising habits of less than 3 days a week (p<0.001). However, the glaucoma OR was significantly high in case of increasing age, with exercising habits of less than 3 days a week, and hypertension (p<0.01), while the OR was significantly low in case of the drinking group (p<0.05). The results of analyzing the odds ratio for the occurrence of glaucoma with the components of metabolic syndrome showed that the OR for glaucoma is significantly low (OR 0.63) in case of concurrently high fasting blood glucose, high triglycerides and low HDL cholesterol levels (p=0.05). Conclusions. Therefore the thorough management of metabolic syndrome and components is needed to prevent glaucoma.

• Survey Research
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• v.11 no.1
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• pp.19-41
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• 2010

Although it is possible to provide statistically reliable estimators of the entire population parameters based on each independent rolling sample, estimators of the small areas may not have the required statistical efficiency. Thus, in general, small area estimators are calculated based on the combined rolling sample after entire rolling sample survey is finished. In this study, we considered the construction of weights that is necessary in the analysis of the combined rolling sample. Unlike the past studies that provided the empirical results for the corresponding specific rolling sample survey, we considered linear models that depends only on design variables and rolling period and provided the corresponding Best Linear Unbiased Predictor(BLUP). Through a simulation study, we proposed the estimators for the population parameters that are robust to model failure and the BLUP under the assumed model. The results are applied to the 4th Korea National Health and Nutrition Examination Survey.

• Korean Journal of Materials Research
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• v.8 no.8
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• pp.775-779
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• 1998

The resonant frequency fo and unloaded quality factor Qu of CoTi-substituted Barium ferrites($\textrm{BaCo}_{x}\textrm{Ti}_{x}\textrm{Fe}_{12-2x}\textrm{O}_{19}$, $1.0\leq\textrm{x}\leq5.0$) were measured at frequencies between 5 to 10GHz using the paralleled copper-plate wave guide method. The measurements showed that the permittivities of CoTi-substituted Barium ferrites(CoTi-BF) increased from 14.7 to 23.4 with the contents of CoTi, x, and the loss tangents had values of $\textrm{10}^{-3}$ order. From these results, CoTi-BF are considered to be very promising materials in microwave devices such as dielctric resonator antennas.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.2
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• pp.211-215
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• 1983

Thirty eight varieties with high uniformity and clearance in grain quality among 70 colored soybeans collected from nation-wide provinces were investigated for their seed morphological and agronomic traits. As for seed morphological traits, grain volumetric size, grain weight, grain length, grain thickness, . hilum length and width were studied on the tendency of statistical dispersion and variations. As a result, four groups could be classified on the basis of 100 grains weight, so as small, medium, large, and super large groups, Also, as for agronomic traits, among others, the tendency of setting in flowering date, maturing date, yield components, and stem weight, stem length were studied on the basis of statistical inter-relationships between above mentioned characteristics. From the above, bigger variations were detected in weighing characters of soybean plants than in duration characters. And the flowering and maturing days showed significant relationships to the stem length, stem weight, also stem length and stem weight to the grain yield.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.4
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• pp.324-331
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• 1981

Sixty five soybean varieties were tested to observe varietal response and to get the basic data for resistant variety breeding to soybean cyst nematode (Heterodera glycines I.). They were classified into five groups, from the most resistant to the most susceptible by decreasing rate of seed weight. A few Korean varieties were included in the most resistant group. In general, early maturing varieties were more susceptible. Total plant weight could be used as an important criterion to select a resistant variety to soybean cyst nematode.