• Journal of the Korean Ceramic Society
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• v.51 no.6
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• pp.527-532
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• 2014

$0.97Bi_{0.5+x}(Na_{0.78}K_{0.22})_{0.5-3x}TiO_3-0.03LaFeO_3$ lead-free piezoelectric ceramics were fabricated by a solid state reaction method. $LaFeO_3$ additives were added to $Bi_{0.5}(Na_{0.78}K_{0.22})_{0.5}TiO_3$ for volatile compensation of bismuth and sodium ions in the sintering process. To create A-site vacancies, the mole ratio and charge valence of A-site ions ($Bi^{3+}$, $Na^+$ and $K^+$) were controlled. The improved piezoelectric properties were observed by addition of $LaFeO_3$ and control of A-site vacancies. In particular, a $d_{33}^*(S_{max}/E_{max})$ value of 614pm/V and an electric field induced strain of 0.33% was observed in $0.97Bi_{0.505}(Na_{0.78}K_{0.22})_{0.485}TiO_3-0.03LaFeO_3$ ceramic.

• FLOWER RESEARCH JOURNAL
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• v.17 no.1
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• pp.44-47
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• 2009

A new spray chrysanthemum(Dendranthema grandiflorum Ramat.) cultivar 'Yes Uri' was originated from a cross between 'SP03-033-02' and 'SP03-005-04'. This cultivar was tested on the characteristics from 2005 to 2007 for the evaluation and selection including shading and retarding culture. The natural flowering time of 'Yes Uri' is the late October, but year-round production is possible by shading, lighting and retarding culture. This cultivar was pompon in flower type with a color of bright yellow(RHS 7A), 13.8 flowers per plant and 91.5 cm of plant hight. The diameter of flower was 4.4 cm and the preference was high at 4.14 ranged up to 5.00. The days to flowering under the short day was 8 weeks and plant was very vigorous. It had resistance to white rust and showed 23.6 days of vase life in autumn season.

• Korean Journal of Breeding Science
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• v.40 no.1
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• pp.15-21
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• 2008

It was previously pointed out that mutation is the ultimate source of variation. Adequate variation is needed for plant breeding if there is a limitation in natural genetic resources. When the ionizing radiation has been known to cause chromosomal and genomic alternations, it is widely used for inducing mutagenesis. The electron beam as an ionizing radiation is the principal physical mutagens that induces mutation and effectively used in plant breeding. Since dose-response relationships of electron beam in plant species are rarely known, we investigated the seed germination rate and early seedling growth of irradiated seeds of creeping bentgrass (Agrostis palustris Huds., cv Penn-A1) with various electron beam irradiating conditions (1, 1.3, 2 MeV at both 0.03 mA and 0.06 mA with dose of 100 Gy (Gray) and 0.03, 1, 1.3, 2 MeV at 0.03 mA with dose of 200 Gy, respectively) using electron accelerator at Korea Atomic Energy Research Institute. The growth parameters in terms of shoot length, primary root length, and secondary root length showed similar response between 0.06 / 1 (mA / MeV) at 100 Gy and 0.03 / 0.3 (mA / MeV) at 200 Gy. Bentgrass seed germination was mainly affected by the intensity of irradiated dose (Gray). Germination rate was lowered as the irradiated dose increased. On the other hand, early seedling growth was mainly governed not by the dose of radiation but by voltage.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.44 no.4
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• pp.399-405
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• 2018

The multi-layered and compartmented hydrogel was designed to examine the self-transforming for developing a 4D mask pack. The hydrogel consisting of two layers with different expansion ratios were fabricated to have specific curvature by self-folding assembly. In addition, the hydrogel compartmented with three different geometries was designed by varying of expansion ratios. The compartmented hydrogel with 0.03, 0. $0,03mm^{-1}$ of curvatures at room temperature was self-transformed with 1.33, 0, $1.33mm^{-1}$of curvatures at $37^{\circ}C$, enhancing the facial adhesion. Overall, this new strategy to prepare the multi-layered and compartmented hydrogel would be actively used in developing the 4D mask pack to self-transform by each facial curvature.

• Microbiology and Biotechnology Letters
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• v.5 no.3
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• pp.113-118
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• 1977

Into the precontaminated farm milk hydrogen peroxide ($H_2O$$_2$) was added at the concentrations ranging from 0.01％ to 0.05％ and kept at 3$0^{\circ}C$ for 16 hours with periodical determinations for viable counts, residual $H_2O$$_2$, and lactic acid. Under the tested conditions the initial level of contaminated bacteria could be arrested from growing at least for 8, 12, and 16 hours by treating the milk with 0.01, 0.02. and 0.03 per cent of $H_2O$$_2$, respectively. Furthermore, when the $H_2O$$_2$concentrations ware limited within the level of 0.03 Per cent the added $H_2O$$_2$was completely decomposed within 12 hours without the aid of external catalase and the decomposition time decreased in parallel with the $H_2O$$_2$ concentrations. A safer use of $H_2O$$_2$for preserving farm milk temporarily by limiting its concentration has been discussed.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.5A
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• pp.485-493
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• 2010

GFRP rebar with ribs resemble those of deformed steel rebar was developed in 2005. It was reported that ribs of the GFRP rebar were sheared off due to the lower shear strength of polymer. In this study, the basic development length of the GFRP rebar was investigated through pull-out tests, models specified in ACI440.1R-03 and -06, and empirical model derived by Cosenza et al. (2002). As a results of pull-out tests, the critical embeddment length, which is defined as the length when failure mode is changed from pull-out to bar fracture, was 20 times of bar diameter for GFRP rebar and was 15 times for steel rebar. It is believed that the basic development of the GFRP rebar is 21 times of bar diameter, which is determined from the application of average bond strength into the model equation specified in ACI440.1R-03. Compared to the model equation in ACI440.1R-06, that in ACI440.1R-03 is recommendable for design purpose. The Cosenza et al.'s model underestimates the basic development length of the GFRP rebar.

• Transactions of the Korean hydrogen and new energy society
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• v.10 no.2
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• pp.119-130
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• 1999

After preparing $Mg_2Ni_{1-x}{^{57}}Fe_x$(x=0.015, 0.03, 0.06, 0.12 and 0.24) alloys, they were studied by $M{\ddot{o}}ssbauer$ resonance. The $M{\ddot{o}}ssbauer$ spectra of x=0.015 and 0.03 alloys exhibit two doublets (doublet 1, 2). That of x=0.06 alloys shows two doublets (doublet 1,2) and one six-line, and those of x=0.12 and 0.24 alloys have only one six-line. The doublet 1 for x=0.015, 0.03 and 0.06 alloys is considered to result from a fraction of Fe in excess showing a superparamagnetic behavior. The doublet 2 is considered to result from the Fe substituted for Ni in the $Mg_2Ni$ phase. The values of isomer shift 0.24 ~ 0.28 mm/s suggest that the iron exist in the state $Fe^{+3}$. The result that the quadrapole splitting of the doublet 2 is not zero shows that the distribution of electrons around the iron is asymmetric. Their values for the doublet 2, 1.20 ~ 1.38 mm/s, approach the value of quadrapole for the oxidation number +3. The six-line showing the magnetic hyperfine interactions results from the iron which has not substituted the nickel in the $Mg_2Ni$ phase. The $M{\ddot{o}}ssbauer$ spectra of the hydrided alloys with x=0.015 and 0.03 show six-line. This suggests that the iron segregates with the hydriding reaction. The analysis results of the $M{\ddot{o}}ssbauer$ spectrum, the variation of magnetization with magnetic field, Auger electron spectroscopy and electron diffraction show the segregation of Ni and the formation of MgO. This is considered to result from the reaction of the $Mg_2Ni$ phase with the oxygen contained in the hydrogen as impurity.

• Korean Journal of Mineralogy and Petrology
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• v.35 no.4
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• pp.469-484
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• 2022

The Janggun Pb-Zn deposit has been known one of the four largest deposits (Yeonhwa, Shinyemi, Uljin) in South Korea. The geology of this deposit consists of Precambrian Weonnam formation, Yulri group, Paleozoic Jangsan formation, Dueumri formation, Janggum limestone formation, Dongsugok formation, Jaesan formation and Mesozoic Dongwhachi formation and Chungyang granite. This Pb-Zn deposit is hydrothermal replacement deposit in Paleozoic Janggum limestone formation. The wallrock alteration that is remarkably recognized with Pb-Zn mineralization at this deposit consists of mainly rhodochrositization and dolomitization with minor of pyritization, sericitization and chloritization. Wallrock alteration is divided into the five zones (Pb-Zn orebody -> rhodochrosite zone -> dolomite zone -> dolomitic limestone zone -> limestone or dolomitic marble) from orebody to wallrock. The white mica from wallrock alteration occurs as fine or medium aggregate associated with Ca-dolomite, Ferroan ankerite, sideroplesite, rutile, apatite, arsenopyrite, pyrite, sphalerite, galena, quartz, chlorite and calcite. The structural formular of white mica from wallrock alteration is (K_0.77-0.62Na_0.03-0.00Ca_0.03-0.00Ba_0.00Sr_0.01)_0.82-0.64(Al_1.72-1.48Mg_0.48-0.20Fe_0.04-0.01Mn_0.03-0.00Ti_0.01-0.00Cr_{0.00As0.01-0.00}Co_0.03-0.00Zn_0.03-0.00Pb_0.05-0.00Ni_0.01-0.00)_2.07-1.92 (Si_3.43-3.33Al_0.67-0.57)_4.00O₁₀(OH_1.94-1.80F_0.20-0.06)_2.00. It indicated that white mica from wallrock alteration has less K, Na and Ca, and more Si than theoretical dioctahedral micas. The white micas from wallrock alteration of Janggun Pb-Zn deposit, Yeonhwa 1 Pb-Zn deposit and Baekjeon Au-Ag deposit, and limestone of Gumoonso area correspond to muscovite and phengite and white mica from wallrock alteration of Dunjeon Au-Ag deposit corresponds to muscovite. Compositional variations in white mica from wallrock alteration of these deposits and limeston of Gumoonso area are caused by mainly phengitic or Tschermark substitution mechanism (Janggun Pb-Zn deposit), mainly phengitic or Tschermark substitution and partly illitic substitution mechanism (Yeonhwa 1 Pb-Zn deposit, Dunjeon Au-Ag deposit and Baekjeon Au-Ag deposit), and mainly phengitic or Tschermark substitution and partly illitic substitution or Na⁺ <-> K⁺ substitution mechanism (Gumoonso area).

• Imaging Science in Dentistry
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• v.32 no.3
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• pp.135-139
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• 2002

Purpose: To determine the proper reference step wedge for digital Cu-Equivalent Image analyzing systems for measurement of bone density. Meterials and Methods : Radiograms of lumbar vertebrae phantom (1g/㎠) with 3 test copper step wedges of 0.03, 0.05 and, 0.1 mm thickness unit were taken and analyzed using NIH image software on a Macintosh personal computer. Measured densities of the lumbar areas in the Cu-Equivalent images made by utilizing 3 different copper stepwedges were compared with a known bone density. Results: The values of r2 for all copper equivalent images were over 0.99. The mean Cu-Eq value of lumbar in copper equivalent image made by a 0.1 mm copper stepwedge was 0.22 ± 0.06 mm and converted to hydroxyapatite density of 1.03 g/㎠. The stepwedges of 0.03 and 0.05 mm produced results having higher values than the actual known bone density. They did not show the blue and green color level that appeared in lumbar on color enhanced image. Conclusion : A copper stepwedge of adequate thickness and range of steps which can express the range of density of bone being measured should be used.

• The Korean Journal of Health Service Management
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• v.6 no.3
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• pp.209-218
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• 2012

The purpose of this study was to provide the effective pain management care for post operative patients through understanding patient's knowledge and attitude about pain-management. The data was collected by distributing structured questionnaires to 200 inpatients in 2 secondary hospitals located in Ulsan, beginning June 28, 2010 to August 11, 2010, and analyzed by t-test, ANOVA, Pearson correlation coefficient. The level of Knowledge about pain management postperations was $6.44{\pm}2.03$. The level of attitude about pain management postperations was $6.92{\pm}1.78$. The significant differences were founded within the inpatient's knowledge about pain management according to the inpatient's demographic data:Age(F=5.55, p=.01), Marital status(t=-2.17, p=.03). The significant differences were founded within the inpatient's attitude about pain management according to the inpatient's demographic data:Job(F=3.45, p=.03). Developing educational material and guidebooks is needed to form more positive about pain-control after operations. This study researched only inpatient's knowledge and attitude about pain-management, but researching nurses, doctors, inpatients and family member's knowledge and attitude should be included in following studies.