• Journal of the Korean Magnetics Society
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• v.24 no.2
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• pp.46-50
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• 2014

The crystallographic properties and cationic distribution of $M_{0.2}Fe_{2.8}O_4$ (M =Mn, Ni, Cu) and $Fe_3O_4$ thin films prepared by sol-gel method have been investigated by X-ray diffraction (XRD) and conversion electron M$\ddot{o}$ssbauer spectroscopy (CEMS). The ionic valence, preferred site, and hyperfine field of Fe ions of the ferrites could be obtained by analyzing the CEMS spectra. The $M_{0.2}Fe_{2.8}O_4$ films were found to maintain cubic spinel structure as in $Fe_3O_4$ with the lattice constant slightly decreased for Ni substitution and increased for Mn and Cu substitution from that of $Fe_3O_4$. Analyses on the CEMS data indicate that $Mn^{2+}$ and $Ni^{2+}$ ions substitute octahedral $Fe^{2+}$ sites mostly, while $Cu^{2+}$ ions substitute both the octahedral and tetrahedral sites. The observed intensity ratio $A_B/A_A$ of the CEMS subspectra of the samples exhibited difference from the theoretical value. It is interpreted as due to the effect of the M substitution for A and B on the Debye temperature of the site. The relative line-broadening of the B-site CEMS subspectra can be explained by the dispersion of magnetic hyperfine fields due to random distribution of M cations in the B sites.

• The Korean Journal of Nuclear Medicine Technology
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• v.12 no.1
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• pp.62-65
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• 2008

Purpose: Vitamin $B_{12}$ and folic acid are type of water-soluble vitamin and those work as a secondary vital enzyme, but especially those are involved in the nuclear DNA synthesis. Those are mainly measured in order to diagnose megaloblastic anemia and to assess the storage of folic acid during pregnancy. It is generally known that the hemolyzed serum is useless for folic acid and vitamin $B_{12}$, but it is not easy to abide by this information because our lab (Samkwang Medical Laboratories) is reference laboratory. We tested how much the extent of hemolyzed serum had influence on the results. Materials and Method: We performed the tests of vitamin $B_{12}$, folic acid. For the hemolysis effect study, we used 40 cases. According to the level of A, B and C groups, each group had 10 samples which were mechanically hemolyzed serum. Results: Hemolysis did not affect the vitamin $B_{12}$ results. However in case of folic acid, the value increased according to the degree of hemolysis. And severe hemolyzed cases had the highest value (greater than 20 ng/ml). Conclusions: Preventing the hemolysis, it has to be informed that blood-collecting, separation and storage are performed more carefully. As you see from the above results, hemolyzed serum is not proper for folic acid test, and hemolysis does not affect the results of vitamin $B_{12}$. However, for the more accurate results, it is necessary to avoid hemolysis.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.5
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• pp.622-628
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• 2006

Kochujang was prepared with various concentrations of Maesil extracts (0, 1, 2, and 5%) and the physicochemical characteristics of Maesil extracts added Kochujang ('Maesil Kochujang') were investigated during aging of 100 days. pH decreased slightly during aging. Titratable acidity, on the other hand, increased with aging, reaching at the highest level at the 40 days of aging and then decreased slowly. The changes of moisture content were complicated in the beginning, but after 60 days it increased slowly. The water activity decreased but salt concentration increased consistently in all samples during aging. L* and a*-values decreased during aging and L*, a*, and b*-values decreased significantly with high amount of Maesil extract in the sample. Soluble solid contents increased slowly while reducing sugar contents increased for up to 40 days and then decreased. Amino nitrogen contents increased steadily after 40 days of aging and they reached at $230.00{\sim}246.00mg%$ upon 100 days of aging.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.6 no.2
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• pp.19-26
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• 1995

The design of broad-band, thin layer electromagnetic wave absorbers usually employs magnetic materials. The common absorber consists of a magnetic material layer bonded to a metal plate at the back. For such structure, a theoretical expression involving six parameters defines the allowable material shape and values of electromagnetic parameters that will produce zero reflection or more practically more than 99% absorption (20dB attenuation). The Secant Method was employed to compute the matching boundary values corresponding to 20dB attenuation. In addition, a search algorithm coupled with the Secant Method was developed to obtain allowable range of material parameters for the design of wave absorbers. These numerical methodes applicable to any six parameters effectively yielded accurate solutions in the least iterations.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.26 no.10B
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• pp.1470-1474
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• 2001

8B/10B 선로부호를 채택한 기가비트 이더넷 PCS 수신측에서는 동기부의 바이트 동기획득과 수신부의 디코딩을 위해 Running Disparity(RD) 에러인 데이터열을 검출해야 한다. 기존의 RD 에러 검출 방법은 직렬 입력 비트에서 RD 에러를 검출하였으나 제안하는 RD 에러 검출 방법은 125MHz 속도의 10비트 데이터열을 받아 4비트열과 6비트열로 나누어 바이트 클럭에 따라 RD를 계산하고 계산된 이전의 RD값과 현재의 RD값을 비교하며 RD 위반 에러 데이터를 검출한다. 이는 기존의 RD 에러 검출 방법이 비트 클럭과 니블 클럭에 따라 RD 에러를 검출하기 때문에 야기되는 초고속 처리에 대한 한계를 해결한 것이며 기가비트 이더넷에 적합한 새로운 RD 에러 검출 방법이다.

• Journal of the korean academy of Pediatric Dentistry
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• v.34 no.4
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• pp.639-645
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• 2007

Removable or fixed space maintainer could be needed if one or some anterior primary teeth were missing, where resin pontics well-matched to natural primary teeth should be demanded to get an esthetic satisfaction. Resin Natural $Teeth^{TM}$(Nissin dental, Japan) is available currently in Korea, which consists of two shades of colors; type A1 and A2. The purpose of this study is to elucidate the colors of the anterior primary resin teeth and to establish the data to compare those with the natural anterior primary teeth. CIE $L^*a^*b^*s$ were measured each three times labially from 17 sets of maxillary four anterior teeth for type A1 and A2 Resin Natural $Teeth^{TM}$ using ShadeEye $NCC^{TM}$(Shofu, Japan) which is one of spectrophotometers. The data were analysed statistically using Kruskall-Wallis Test and Mann-Whitney U Test. The results were as follows : 1. There were smaller teeth color differences in group A1 than in group A2 when it comes to distributions of ${\Delta}E$, $L^*$ and $b^*$. There were no statistically significant differences of $a^*$ between teeth in the same group(P>0.05). 2. ${\Delta}E$ in group A1 and A2 (maximum ${\Delta}E{\le}1.23$) were very small, which could not be discerned by eyesight. ${\Delta}E$ between mean CIE $L^*a^*b^*s$ of group A1 and A2 was 3.97, which could be discernible by eyesight. 3. Mean measurements of group A1 were $L^*=73.8$, $a^*=-1.8$, $b^*=-4.7$, and those of group A2 were $L^*=75.8$, $a^*=-2.7$, $b^*=-1.4$. It would be recommended that resin teeth compatible to the colors of the natural primary ones needed to be developed by investigating in vivo study.

• The KIPS Transactions:PartB
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• v.12B no.2 s.98
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• pp.203-208
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• 2005

We propose an algorithmic approach for handling linguistic values defined in the same linguistic variable. Using the proposed approach, we can explicitly capture the differences of individuals' subjectivity with respect to linguistic values defined in the same linguistic variable. The proposed approach can be employed as a useful tool for discovering hidden relationship among linguistic values defined in the same linguistic variable. Consequently, it provides a basis for improving the precision of knowledge acquisition in the development of fuzzy systems including fuzzy expert systems, fuzzy decision tree, fuzzy cognitive map, ok. In this paper, we apply the proposed approach to a collective linguistic assessment among multiple experts.

• The KIPS Transactions:PartB
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• v.9B no.3
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• pp.271-276
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• 2002

The test statistic in ANOVA tests has a single or doubly noncentral F distribution and the noncentral F distribution is applied to the calculation of the power functions of tests of general linear hypotheses. Although various approximations of noncentral F distribution are suggested, they are troublesome to compute. In this paper, the calculation of noncentral F distribution is applied to the neural network theory, to solve the computation problem. The neural network consists of the multi-layer perceptron structure and learning process has the algorithm of the backpropagation. Using fables and figs, comparisons are made between the results obtained by neural network theory and the Patnaik's values. Regarding of accuracy and calculation, the results by neural network are efficient than the Patnaik's values.

• Food Science and Preservation
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• v.10 no.3
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• pp.388-393
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• 2003

Citrus peel extract was prepared using 70％ ethanol solution by two extraction conditions (20$^{\circ}C$ for 72 hours and 85$^{\circ}C$ for 3 hours). The effect of gamma-irradiation on the changes of physiological activity also investigated at 0, 5, 10 and 20 kGy of absorbed doses. Color characteristics, DPPH radical scavenging, tyrosinase inhibition and nitrite scavenging activities of the extracts were measured at 41$^{\circ}C$ for 30 days. Color values were different by extraction methods at the initial stage, which heat-extracted sample had lower L$\^$＊/ - but higher a$\^$＊/ - and b$\^$＊/ -values than those extracted at room temperature. Irradiation changed color of the extract lighter by increasing Hunter color L$\^$＊/ - and a$\^$＊/ -values. DPPH radical scavenging, tyrosinase inhibition and nitrite scavenging activities were not affected by either extraction methods or irradiation but significantly reduced by storage time. Therefore, when the cost-effective extraction methods is selected, the citrus peel extracts, which is a major byproduct in citrus processing, could be used as a functional material in various applications.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.2
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• pp.77-86
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• 2002

Soil color characteristics were measured by a optical instrument, colorimeter, comparing with the conventional Munsell color chart and related to the chemical properties of soils. Total of the 67 experimental soils were taken from tobacco fields that located at Cheongwon, Enmseong, Boeun, Goesan, Jincheon, and Chungju countries in Chungbuk Province having the 29 soil series including Samgag. The values of L, a, and b measured by colorimeter were closely related with hue, value, and chroma of Munsell color chart, respectively, indicating the quantitative measurement of soil color characteristics. The standard deviations in measurement for L, a, and b values was smaller in soil sample passed by 0.5 mm sieve than 2 mm sieve, suggesting that soil particle size less than 0.5 mm was better condition for colorimeter measurement. The values of L and b measured by colorimeter showed a tendency to decrease as increase of soil moisture content but nearly on difference with moisture condition for the value of a. However, correlation coefficient between air dry samples and wet soil samples(soil moisture retension of -10 hPa) for measurements of L, a and b value were more than 0.9 showing the same tendency in measurement. Consequently, air dry soil passed by 0.5 mm sieve was recommended to desirable conditions for stable measurement by colorimeter. The measured values by colorimeter were significantly correlated with organic matter, CEC, exchangeable Ca and Mg, showing the highest correlation coefficient between L value and organic matter.