• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.27 no.11
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• pp.707-711
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• 2014

The $0.99Bi_{0.5}(Na_{0.78}K_{0.22})_{0.5}TiO_3-0.01LaAlO_3$, $0.01LaMnO_3$ or $0.01LaFeO_3$ (0.99BNKT-0.01LA, 0.01LM or 0.01LF) ceramics were prepared by a conventional mixed mothod. The structure and morphology of the lead free ceramics were characterized by XRD (X-ray diffraction) and FE-SEM (field emission scanning electron microscopy). XRD results indicated that the BNKT ceramics modified by LA, LM or LF induced a transition from a ferroelectric tetragonal to a non-polar pseudo-cubic phase, leading to decrease in the remnant polarization ($P_r$) and coercive field ($E_c$) in the P-E hysterisis loops. The effects of the BNKT ceramics modified by La-based $ABO_3$ pervskite structure on the electric-field induced strain were investigated, and the largest normalized unipolar strain ($S_{max}/E_{max}$) was found in BNKT-0.01LF ceramic.

• The Korean Journal of Zoology
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• v.21 no.1
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• pp.9-17
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• 1978

The blood samples collected from 863 school boys living in Seoul, Kwangju, Pusan and Cheju were tested for studies on the distributions and frequencies of ABO, MNSs, Rh, Diego, Duffy, Kell, Kidd and P blood groups. The $I^B$ gene frequencies appeared to be a cline, and this is decreased gradually from north to south except the Cheju population, but on the other hand those of $I^A$ gene increased oppositely. In Koreans A type of ABO group increased during past fifty years while B type decreased. $Ig^M$ gene frequencies also decreased from north to south district in Korea except Cheju. And the frequency of $Ig^M$ in Koreans was 0.518 which is between those of the north Chinese and the Japanese. In general Rh negative was 0.26 percent, and CCDee phenotype was of the highest frequency among all phenotypes, showing 42.41 percent, CcDEe, about 34% and ccdee, 0.087%. The frequencies of most Rh phenotypes in Koreans were close to those of the Japanese rather than to those of the Chinese and the Thais. Di(a+) type was 6.633 percent, and Fy(a+) and Fy(b+) type were 99.267 percent and 13.832 percent respectively. K+ type was observed only one case in Seoul. The frequencies of Jk(a+) and P+ type were the most varied depending on the populations studied.

• Journal of applied mathematics & informatics
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• v.7 no.1
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• pp.215-222
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• 2000

A multigrid algorithm is developed for solving the one- dimensional initial boundary value problem. The numerical solutions of linear and nonlinear Burgers; equation for various initial conditions are studied. The stability conditions are derived by Von -Neumann analysis . Numerical results are presented.

• Journal of applied mathematics & informatics
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• v.28 no.3_4
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• pp.797-804
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• 2010

The aim of this paper is to investigate the global stability, periodic nature, oscillation and the boundedness of solutions of the difference equation $x_{n+1}\;=\;\frac{A+Bx_{n-1}}{C+Dx_n^2}$, n = 0, 1, 2, ... where A, B are nonnegative real numbers and C, D > 0.

• Proceedings of the Zoological Society Korea Conference
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• 1996.10a
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• pp.247.1-247
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• 1996

No Abstract, See Full Text

• Proceedings of the KIPE Conference
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• 2005.07a
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• pp.411-413
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• 2005

This paper proposes a modeling of wind turbine simulator which includes the dynamic characteristics such as pitch angle control, torsional vibration, and tower effect. Simulation results using PSCAD are provided to show the wind turbine simulator performance.

• Journal of the Korean Ceramic Society
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• v.44 no.10
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• pp.537-541
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• 2007

Microwave dielectric properties of $0.95 Ca_{0.85}Nd_{0.1}TiO_3-0.05LnAlO_3$ (Ln=Sm, DH, Er) were investigated as a function of sintering temperature and lanthanide ion type. A single perovskite phase with an orthorhombic structure was obtained throughout the entire range of composition. The dielectric constant (K) was dependent upon the dielectric polarizabilities and the B-site bond valence in the $ABO_3$ perovskite structure. The quality factor (Qf) of the specimens with $ErAlO_3$ was smaller than those with $SmAlO_3\;and/or\;DyAlO_3$ due to the smaller grain size. The temperature coefficient of resonant frequency (TCF) could be controlled from $107.28ppm/^{\circ}C$ at Ln=Sm to $87.23ppm/^{\circ}C$ at Ln=Er due to the changes of B-site bond valence in the $ABO_3$ perovskite structure.

• Toxicological Research
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• v.24 no.4
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• pp.297-305
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• 2008

This study was carried out to measure the concentration of heavy metals (Pb, Mn, Cr, Cd, Ni, Zn, and Cu) in water and Bolti fish (Tilapia nilotica) samples collected from Rasheed branch of River Nile, north of El-Giza Governorate, Egypt by atomic absorption spectrophotometry. The investigated districts through which the branch passes include El-Manashi, Gezzaya, El Katta, Abo Ghaleb and Wardan. Based on WHO and FAO safety reference standards, the results of the current study showed that water and fish tissues were found to contain heavy metals at significantly variable concentration levels among the investigated districts. They were polluted with respect to all the metals tested at Gezzaya district. However, the levels of analyzed metals in water and fish tissues were found lower than legal limits in other districts. The heavy metals showed differential bioaccumulation in fish tissues of the different districts as the accumulation pattern (as total heavy metal residues) was district dependant as follow: Gezzaya > Wardan > El Katta > Abo Ghaleb > El Manashi.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 1999.11b
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• pp.115-119
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• 1999

During mechanical pulp production and blcaching wood components, such as extractives, carbohydrates and lignin are dissolved and dispersed into the process waters. These components are called dissolved and colloidal substances(DCS). DCS can accumulate during water circulation and can in turn affect paper machine runnability and also the strength and optical properties of the paper. In this work DCS fraction origination from TMP process were treated with enzymes acting on triglycerides. glucomannans, and lignin and the effect of enzymatic treatments on the water composition as well as sheet properies were evaluated. Lipases were found to modify the chemical structure of the extractives resulting in more hydrophilic fibre surface and subsequent improvement in the sheet strength properties. Mannanase treatment, on the other hand, destabilized pitch. As a result, aggregation of pitch to the fibres was observed which in turn resulted in impaired strength properties. Laccase could effectively polymerize lignans and the reaction products seemed to be sorbed onto the fibres.

• Journal of Korean Academy of Nursing
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• v.33 no.1
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• pp.51-59
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• 2003

Purpose: The purpose of the study is to investigate the relationship between total serum bilirubin(TSB) and transcutaneous bilirubinometry(TcB) in neonates with jaundice. Method: TcB from various sites(forehead, sternum, abdomen, buttock, hand, dorsalis-pedia) was measured using a JM-102 in a total of 102 neonate, 42 female and 60 male, with the mean 37.5 gestational week and the mean 2,903 gram of birth weight, as well as TSB from capillary punctures. Result: The mean bilirubin was 11.73 in serum, 20.55 on the forehead, 17.23 on the sternum, 16.19 on the abdomen, 18.22 on the buttock, 15.83 on the hand and 15.49 on the dorsalis-pedia. The relationship between TSB and TcBs were formulated by simple regression with 0.406 < r < 0.668(p < .000). A higher relationship was revealed between TSB and TCB at the forehead in infants of full-term, ABO incompatibility, and Hb greater than 16 mg/dl(r =0.725, 0.790, and 0.717, retrospectively). Phototherapy altered the measurement of TcB per site. Conclusion: TcB on the forehead is a reliable, noninvasive and convenient measurement of TSB in normal infants(Institutions need to establish quantitative equations representing the specific relationship between TSB and TCB according to the hemodynamic problems of infants such as ABO incompatibility, or low Hb).