• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2002.05a
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• pp.7-8
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• 2002

• Journal of Korean Society of Environmental Engineers
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• v.27 no.3
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• pp.253-261
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• 2005

Catalytic wet oxidation of ppm levels of trichloroethylene (TCE) in water has been conducted using $TiO_2$-supported cobalt oxides at a given temperature and weight hourly space velocity. 5% $CoO_x/TiO_2$ might be the most promising catalyst for the wet oxidation at $36^{\circ}C$ although it exhibited a transient behavior in time on-stream activity. Not only could the bare support be inactive for the wet decomposition reaction, but no TCE removal also occurred by the process of adsorption on $TiO_2$ surface. The catalytic activity was independent of all particle sizes used, thereby representing no mass transfer limitation in intraparticle diffusion. Characterization of the $CoO_x$ catalyst by acquiring XPS spectra of both fresh and used Co surfaces gave different surface spectral features of each $CoO_x$. Co $2p_{3/2}$ binding energy of Co species exposed predominantly onto the outermost surface of the fresh catalyst appeared at 781.3 eV, which is very similar to the chemical states of $CoTiO_x$ such as $Co_2TiO_4$ and $CoTiO_3$. The spent catalyst possessed a 780.3 eV main peak with a satellite structure at 795.8 eV. Based on XPS spectra of reference Co compound, the TCE-exposed Co surfaces could be assigned to be in the form of mainly $Co_3O_4$. XRD measurements indicated that the phase structure of Co species in 5% $CoO_x/TiO_2$ catalyst even before reaction is quite comparable to the diffraction lines of external $Co_3O_4$ standard. A model structure of $CoO_x$ present on titania surfaces would be $Co_3O_4$, encapsulated in thin-film $CoTiO_x$ species consisting of $Co_2TiO_4$ and $CoTiO_3$, which may be active for the decomposition of TCE in a flow of water.

• Journal of the Korean Magnetics Society
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• v.16 no.1
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• pp.6-10
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• 2006

The sulphur spinel $FeCr_{2-x}M_xS_4$(M=Ga, In) have been studied with Mossbauer spectroscopy, x-ray diffraction (XRD), and vibrating sample magnetometer. The XRB patterns for samples $FeCr_{2-x}M_xS_4$(M=Ga, In: x=0.1, 0.3) reveal a single phase, which the Ga and In ions are partially occupied to the tetrahedral (A) site. The Neel temperature for the Ga substituted samples increases from 180 to 188 K, with increase from x=0.1 to 0.3. While, it decreases from 173 to 160 K, for the In substituted samples of the x=0.1 and 0.3, respectively. The Mossbauer spectra were collected from 4.2 K to room temperature. We have analyzed the Mossbauer spectra using eight Lorentzian lines fitting method for the $FeCr_{2-x}In_xS_4$(x=0.1) at 4.2 K, yielding the 1311owing results; $H_{hf}=146.0kOe,\;{\Delta}E_Q=1.88mm/s,\;\theta=36^{\circ},\;\phi=0^{\circ},\;\eta=0.6$, and R=1.9. The Ga ions enter into the both sites octahedral (B) and tetrahedral (A), simultaneously the same amounts of Fe ions migrate from the A to the B site, this result is an agreement with XRD results, too. The ${\Delta}E_Q$ of the A and B site in Mossbauer spectra of the samples $FeCr_{2-x}Ga_xS_4$(x=0.3) are 0.83 and 2.94mm/s, respectively. While they are 0.56 and 2.36mm/s for the $FeCr_{2-x}In_xS_4$(x=0.3). It is noticeable that the ${\Delta}E_Q$ for the Ga doped samples are larger than that of the corresponding In doped samples, in spite of the larger ionic radius for In ions. The bond lengths of Cr-S, for the Ga and In doped samples (x=0.3) are found to be 2.41 and $2.43\;{\AA}$, respectively. We interpret that the larger covalence effect from the smaller bond length induces a large asymmetric charge distribution. Finally, it gives a large quadrupole interaction.

• Korean journal of applied entomology
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• v.50 no.2
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• pp.151-156
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• 2011

Economic injury levels (EILs) and economic control threshold (ET) were estimated for the Tea red spider mite, Tetranychus kanzawai Kishida(Acari, Tetranychidae) in Rubus coreanus Miquel. T. kanzawai density increased until the early-July and thereafter decreased in all plots except the non-innoculation plot where initial density of the mite were different each 0, 5, 10, 20 and 40 adults per plant branch on May 7 in 2008. And the occurrence of the densities were increased higher innoculated density than different innoculation density. The yield was decreased with increasing initial mite density and thereby the rates of yield loss was increased with increasing initial mite density. And T. kanzawai occurrence density, yields and the rates of yield loss, where initial density of the mite were different each 0, 2, 5, 10 and 20 adults per plant branch on May 8 in 2009 were similar tendency to 2008 year results. The relationship between initial T. kanzawai densities and the yield losses was well described by a linear regression, Y = 0.6545X + 3.0425 ($R^2$ = 0.93) in 2008, Y = 0.9031X + 2.0899($R^2$ = 0.96) in 2009. Based on the relationship, the number of adults per plant branch(EILs) which can cause 5% loss of yield was estimated to be approximately 3.0 in 2008 and 3.2 in 2009. And the ET was estimated to be approximately 2.4 in 2008 and 2.6 in 2009. The relationship between initial T. kanzawai densities and occurrence density of mid-May considering the best spray timing against T. kanzawai was well described by a linear regression, Y = 0.471X + 2.495($R^2$ = 0.95) in 2008, Y = 0.9938X + 3.1858($R^2$ = 0.96) in 2009. Based on the relationship, the number of adults per leaf(ET) in mid-May which can cause 5% loss of yield was estimated to be approximately 3.6 in 2008 and 5.8 in 2009.

• Clinical and Experimental Pediatrics
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• v.45 no.12
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• pp.1484-1490
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• 2002

Purpose : The purpose of this study was to look at prevalences of abnormal serum aminotransferase levels and abnormal serum total cholesterol levels among adolescents with obesity in Seoul area. Methods : Body mass index[$BMI(kg/m^2)$], serum aspartate aminotransferase(AST) alanine aminotransferase( ALT), and total cholesterol levels were measured in 26,876 adolescents(male : 13,287, female : 13,589) of first grade of high school in Seoul between the ages of 15 and 16 years, enrolled in a large health examination survey by Seoul School Health Center(SSHC) in 2001. Obesity was defined as BMI more than 95th percentile for age and sex and normal weight was defined as BMI between 25th percentile and 75th percentile for age and sex. Abnormal levels of AST, ALT and total cholesterol were defined as more than 95th percentile for age and sex. Results : The BMI at 95th percentile was 28.7 in males and 26.9 in females. The prevalence of abnormal AST levels was higher in obesity group than in normal weight group. In males, those were 23.7% and 3.7%, respectively(P<0.01, $x^2-value$ : 529.2). In females, those were 11.8% and 4.9 %, respectively(P<0.01, $x^2-value$ : 56.3). The prevalence of abnormal ALT levels was significantly higher in the obesity group compared with the normal weight group. In males, those were 33.9% and 1.7%, respectively(P<0.01, $x^2-value$ : 1,693.4). In females, those were 22.3% and 3.9%, repectively(P<0.01, $x^2-value$ : 397.6). The prevalence of abnormal total cholesterol levels was higher in the obesity group than in the normal weight group. In males, those were 16.8% and 3.5%, respectively(P<0.01, $x^2-value$ : 268.3). In females, those were 9.0% and 5.4%, respectively(P<0.01, $x^2-value$ : 14.2). Conclusion : This study revealed that the prevalences of abnormal AST, ALT and total cholesterol level were higher in the obese group than in the normal weight group.

• Journal of Embryo Transfer
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• v.30 no.1
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• pp.45-50
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• 2015

The purpose of this study is to produce wanted sex progeny of genetically confined White Hanwoo (albinism) with preselected sex sperm. One bull of White Hanwoo was chosen for semen donor and X sperm was sorted by MoFlo XDP cell sorter. To compare the pregnancy and birth rates, KPN straw was used as control, total number of unsorted sperm was $20{\times}10^6/straw$. Sexed X frozen semen with $20{\times}10^6$ cells or $4{\times}10^6$ cells per straw were in seminated twice on Hanwoo heifers. The abnormality of the sexed X semen was $24.9{\pm}7.31%$ and distal reflex abnormality of mid piece was significantly (p<0.05) higher (11.7%) compared with that of KPN 768 (5.6%). There were no differences on the pregnancy and birth rates between $2{\times}10^6$ cells or $4{\times}10^6$ cells of X-sperm but KPN semen showed significant differences (p<0.05). The pregnancy rates of KPN 768, $2{\times}10^6$ cells and $4{\times}10^6$ cells X-sperm of White Hanwoo cattle were 85.0%, 26.3% and 50%. The birth rates were 80.0%, 15.8% and 21.4%, respectively. The female offspring rates of KPN 768, $2{\times}10^6$ cells and $4{\times}10^6$ cells X-sperm of White Hanwoo cattle were 43.8%, 100% and 100% (p<0.05). These results indicated that sex sorted White Hanwoo could be used for the production of wanted progeny with $2{\times}10^6$ cells/straw for AI. To increase the efficiency of calf production, the sperm number of sex sorted semen will be optimized for sex selection of White Hanwoo progeny.

• The Korean Journal of Ceramics
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• v.1 no.2
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• pp.91-95
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• 1995

Polycrystalline bismuth- and aluminum- substituted dysporsium and yttrium iron garnet (Bi2R3-xAlyFe5-yO12, R=Dy or Y, $0\leqx\leq3, \; 0\leqy\leq3$) films have been prepared by pyrolysis. The crystallization temperatures, the solubility limit of bismuth ions into the garnet phase, and magnetic and magneto-optic properties of the films have been investigated as a function of bismuth and aluminum concentration. It was found that the crystallization temperatures as a function of bismuth and aluminum concentration. It was found that the crystallization temperatures of these films rapidly decreased as bismuth concentration. It was found that the crystallization temperatures of these films rapidly decreased as bismuth concentration (x) increased up to x=1.5 and then remained temperatures of these films rapidly decreased as bismuth concentration (x) increased up to x=1.5 and then remained unchanged at x>1.5, whereas, showed no changes as aluminum concentration (y) increased up to y=1.0 and then gradually increased at y>1.0. The solubility limit of bismuth ions was x=1.8 when y=0 but increased to x=2.3 when y=1.0. It was demonstrated that the magnetic and magneto-optic properties of the dysprosium iron garnet films could be tailored by bismuth and aluminum substitution suitable for magneto-optic recording as follows. The saturation magnetization and coercivity data obtained for the films indicated that the film composition at which the magnetic compensation temperature became room temperature was y=1.2 when x=1.0. Near this composition the coercivity and the squareness of the magnetic hysteresis loop of the films were several kOe and unit, respectively. The Curie temperatures of the films increased with the increase of x but decreaed with the increase of y, and was 150-$250^{\circ}C$ when x=1.0 and y=0.6-1.4. The Faraday rotation at 633 nm of the films increased as x increased but decreased as y increased, and was 1 deg/$\mu\textrm{m}$ when x=1.0 and y=1.0. Based on the data obtained, the appropriate film composition for magneto-optic recording was estimated as near x=1.0 and y=1.0 or $BiDy_2AlFe_4O_{12}$.

• Journal of the Korean Chemical Society
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• v.41 no.11
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• pp.594-599
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• 1997

Lithium nickel oxide ($Li_{2x}Ni_{1-x}O$) thin films have been prepared by the RF sputtering of lithiated nickel oxide target, where the film microstructure was controlled by the sputtering atmosphere $(Ar/O_2)$ and the substrate temperature ($T_s=50/230^{\circ}C$). From the transmission electron microscopic analysis, it is found that the most porous film with the grain size of $∼80\AA$ could be fabricated under the sputtering atmosphere of $P(O_2)=8{\times}10^2$ mbar with the $$T_s$=50^{\circ}C.$ In the optical and electrochemical studies, the$Li_{2x}Ni_{1-x}O$ films exhibit a significant electrochromic property in association with the lithium insertion/deinsertion process. The amount of charge insertion ($Q_i$) and the optical density (OD) variation depend on the crystallinity of the film as well as its thickness, and for the $Li_{2x}Ni_{1-x}O$ film (170 nm thickness) prepared under $O_2$ atmosphere and $T_s=50^{\circ}C$, the OD could be increased up to ∼1.3 by the charge insertion with $Q_i=30\;mC/cm^2.$

• Journal of agricultural medicine and community health
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• v.35 no.1
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• pp.36-45
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• 2010

Objectives: This study was performed to examine the healthy lifestyle influenced on the metabolic syndrome among the elderly in the rural area. We examined the changes of risk factors of metabolic syndrome after two years. Method: Out of 134 who did health screening at the J county health center from July 1 to August 31, 2006, 65 aged people confirmed to metabolism syndrome were selected as subjects. For the final analysis, 62 aged people who revisited after two years were selected our subjects. The data were analyzed using SPSS PC+ 12.0 program for descriptive, Chi-square test, t-test and ANOVA analysis. Result: The result of this study indicated that 62 metabolic syndrome patients in 2006 decreased into 53, and women were higher than men. The difference in the metabolic syndrome came from level of education, smoking, health practices, and past illness history. Conclusion: Therefore, the change of lifestyle needs to be induced by the level of education, and for the group of smoking, non-exercise, and past illness history not only regular checkups to prevent metabolic syndrome but also education to have interest on themselves may need intensively.

• Journal of Korean Physical Therapy Science
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• v.9 no.3
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• pp.19-29
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• 2002

This study questionnaires 166 inpatients and outpatients with stroke in 8 hospitals, including Wonkwang University Gwangju Korean Hospital from July 2 to 31, 2001 in order to find out the influence of general nature, smoking, drinking, obesity, and perception of saltness of patients with stork on the outbreak of stroke and to examine important factors by dividing into hemorrhagic and ischemic stroke. Finally, collected data is analyzed statistically, using SPSS 7.5 statistics package. This study reaches a conclusion as follows. 1. For general nature, 86(51.8%) patients have hemorrhagic stroke and 80(48.2%), ischemic stroke in the rate of 1.59:1(male:female), suggesting that male's outbreak is more than female's. Outbreak age is ranged from 20 years to 90 years in order of 60's, 50's, and 40's. 50's-60's accounts for more than half percentage. 2. For smoking, 73(71.6%) of male patients has smoking experience and their 562% has ischemic stroke. Their cross-analysis for hemorrhagic and ischemic stroke shows significant difference with $x^2=3.90$(p<0.05). 48.6% of patients with smoking experience is ranged from 1 to 10 a day in smoking quantity. 3. For drinking, 90(88.2%) of male patients has drinking experience and their 53.3% has hemorrhagicstroke. Their cross-analysis for hemorrhagic and ischemic stroke shows no significant difference with x2=3.40(p<0.1). 59.3% of patients with drinking experience is classified as a overdrinking group. 4. For obesity, low weight is 8(4.8%): normal, 111(66.9%): excessive, 40(24.1%), and obesity, 7(4.2%). In patients with hemorrhagic stroke, excessive weight and obesity are somewhat high(33.7%). The cross-analysis for male's hemorrhagic and ischemic stork by dividing BMI into more and less than 25 shows no significant difference with x=3.52(p<0.1). 5. For perception of saltness, 21(12.7%) patients eat flat: 76(45.8%) normally, and 69(41.5%), saltily. Many patients with ischemic stroke are classified as a group who eat saltily. The cross-analysis for male's hemorrhagic and ischemic stroke shows signifiant difference with x2=10.99(p<0.05). As this study has small sample and selects inpatient and outpatient in certain local hospital, it is difficult to generalize. But the cross-analysis of male's hemorrhagic and ischemic stroke shows signifiant difference in smoking and perception of saltness. Drinking and obesity are more important factors in hemorrhagic stroke and smoking and perception of saltness in ischemic stroke.