• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.3
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• pp.465-471
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• 2007

The one step type pole and two step type pole are used in KEPCO's distribution system. The neutral current increases in three-phase four-wire distribution system due to unbalanced load. Usually, power line and communication line are installed at contiguity by effect of topography in Korea. To this end, the damages such as electrostatic induction, electromagnetic induction and harmonic induction generated by induced voltage and current are occured in power line and communication line. This paper calculates the neutral current in KEPCO's distribution system using EMTP by composing various simulated conditions. Also, these results are verified by vector analysis.

• Bulletin of the Korean Chemical Society
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• v.7 no.1
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• pp.63-66
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• 1986

Concentration dependences of the isotropic Raman line widths for the $ {\nu}_1$ (C-H and C-D) and the ${\nu}_2\;(C{\equiv}N)$ modes for $CH_3CN$ and $CD_3CN\;in\;CCl_4$ solutions have been investigated. For the ${\nu}_1$ modes, the dephasing seems to be a good description for the isotropic line broadening in $CCl_4$ solution even though the concentration fluctuation can reproduce the experimental results also. For the ${\nu}_2$ modes, the concentration fluctuation was the dominant mechanism for the concentration-dependent line broadening.

• International Journal of CAD/CAM
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• v.2 no.1
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• pp.23-28
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• 2002

This paper presents an efficient line-offset algorithm for general polygonal shapes with islands. A developed sweep-line algorithm (SL) is introduced to find all self-intersection points accurately and quickly. The previous work is limited to handle polygons that having no line-segments in parallel to sweep-line directions. The proposed algorithm has been implemented in Visual C++ and applied to offset point sequence curves, which contain several islands.

• Preventive Nutrition and Food Science
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• v.11 no.1
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• pp.17-24
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• 2006

Methanolic and aqueous extracts from 37 seaweed species (10 green and 27 brown seaweeds) collected from Jeju Island coast were prepared at high ($70^{\circ}C$) and room ($20^{\circ}C$) temperatures and examined for cytotoxic activity against 4 tumor cell lines: U937 (human monoblastoid leukemia cell line), HL60 (human promyelocytic leukemia cell line), HeLa (woman cervical carcinoma cell line) and CT26 (mouse colon carcinoma line). Both MeOH extracts of Desmarestia tabacoides and Dictyota dichotoma possessed strong cytotoxic activities against all the tumor cell lines tested, but the aqueous extract exhibited no activity. On the other hand Ecklonia cava showed strong cytotoxic activities for the $20^{\circ}C$ aqueous extract against the three tumor cells except HeLa cell. Sagassum coreanum and Sagassum siliquastrum $20^{\circ}C$ aqueous extracts also exhibited strong cytotoxic activities against U937, HL60, HeLa cells. Even though green seaweeds showed less activity than brown seaweeds, $20^{\circ}C$ aqueous extracts of Codium contractum and Codium fragile exhibited strong cytotoxic activities against HL60 or CT26 cells, respectively.

• Journal of The Korean Astronomical Society
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• v.37 no.4
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• pp.193-197
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• 2004

Anomalies in the far-infrared [C II] 158 ${\mu}m$ line emission observed in the central one-kiloparsec regions of spiral galaxies are reviewed. Low far-infrared intensity ratios of the [C II] line to the continuum were observed in the center of the Milky Way, because the heating ratio of the gas to the dust is reduced by the soft interstellar radiation field due to late-type stars in the Galactic bulge. In contrast, such low line-to-continuum ratios were not obtained in the center of the nearby spiral M31, in spite of its bright bulge. A comparison with numerical simulations showed that a typical column density of the neutral interstellar medium between illuminating sources at $hv {\~} 1 eV $ is $N_H {\le}10^{21}\;cm^{-2}$ in the region; the medium is translucent for photons sufficiently energetic to heat the grains but not sufficiently energetic to heat the gas. This interpretation is consistent with the combination of the extremely high [C Il]/CO J = 1-0 line intensity ratios and the low recent star-forming activity in the region; the neutral interstellar medium is not sufficiently opaque to protect the species even against the moderately intense incident UV radiation. The above results were unexpected from classical views of the [C II] emission, which was generally considered to trace intense interstellar UV radiation enhanced by active star formation.

• Journal of Welding and Joining
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• v.3 no.1
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• pp.11-21
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• 1985

The line heating is a thermoplastic working technique which is used in bending work of steel plate and in correcting the distortion of welded structure. This method is considerably effective when the water-cooling is followed. In this study, an investigation was accomplished to find the effects on the change of material properties when the line heating was applied on the high tensile steel plate of 50kg/mm^2$ grade. Some steel plates were heated to various temperatures and then cooled with water or in the air. In this study, the author measured the angular distortion continuously during line heating to find out the relation between the bending efficiency and heating or water-cooling temperature. Furthermore, its material properties were examined by the V-notch Charpy impact test, the microscope observation and the Vickers hardness test. As results, the followings were clarified. (1) The amount of angular distortion increases as the heating temperature or the water-cooling temperature rises. (2) When the steel plate is heated between 700.deg. C and 900.deg. C, and then is water-cooled over 700.deg. C, some brittle structure is observed. But if the temperature of water-cooling is below 700.deg. C, no brittle one is found. (3) When the steel plate is heated over 800.deg. C and is cooled in the air, there is no unfavrable effect.

• Korean Journal of Poultry Science
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• v.29 no.2
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• pp.81-88
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• 2002

The objective of this study was to investigate the line-by-feed additive interaction on egg traits and yolk cholesterol level in laying hens. Hy-line W-98 (white shell line) and Hy-line Brown (brown shell line) were used as experimental stocks and three groups were assigned in each line. The age of hens used in this study were from 40- to 46-wk-old. Two different levels of chitosan were also used as additive in chicken diet. The first (CH$_{30}$) and second (CH$_{60}$) experimental groups were fed basal diet added 30mg and 60mg chitosan/kg feed, respectively. And the control group (CON) hens were fed with basal diet only. The eggs were collected and analyzed at the end of 40, 42, 44, and 46-wk-old. In the mean egg weight, the CH$_{30}$ in Hy-line Brown was significantly heavier (P<0.05) than CON, but the CH$_{30}$ in Hy-line W-98 was significantly lighter (P<0.05) than CON. Whereas, the mean egg weight did not significantly differ between CH$_{60}$ and CON in both line. The mean albumen percentage in Hy-line Brown did not show significant between experimental groups and control group. On the other hand, the mean albumen percentage of CH$_{60}$ in Hy-line W-98 was significantly lower (P < 0.05) than that of CON, but there was no significantly different between CH$_{30}$ and CON. In the mean yolk percentage, it showed a reverse trend as shown in the mean albumen percentage; there were significantly higher (P<0.05) in CH$_{60}$ than in CON fur the Hy-line W-98, and higher in CH$_{30}$ than in CON for the Hy-line Brown. However, the mean shell percentages did not significantly differ between experimental groups and control group in both lines. In the mean yolk cholesterol levels, the CH$_{30}$ and CH$_{60}$ in both lines were lower by 0.46 mg ∼2.80 mg per gram yolk than CON. Although the interaction effect of line-by-supplementing level of chitosan in hens diet on the pooled mean of yolk cholesterol level was no significant, it showed a highly significant interaction (P<0.01) at three of four experimental ages.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.18
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• pp.7731-7735
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• 2014

Colorectal cancer (CRC) is the third most common cause of death due to cancer in the worldwide and the incidence is also increasing in Turkey. Our present aim was to investigate any association between germ-line methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C polymorphisms and CRC risk in Turkey. A total of 86 CRC cases and 212 control individuals of the same ethnicity were included in the current study. Peripheral blood-DNA samples were used for genotyping by StripAssay technique, based on the reverse-hybridization principle and real-time PCR methods. Results were compared in Pearson Chi-square and multiple logistic regression models. The MTHFR 677TT (homozygous) genotype was found in 20.9% and the T allele frequency 4.2-fold increased in CRC when compared with the control group.The second SNP MTHFR 1298CC (homozygous) genotype was found in 14.0% and the C allele frequency 1.4-fold elevated in the CRC group. The current data suggest strong associations between both SNPs of germ-line MTHFR 677 C>T and 1298 A>C genotypes and CRC susceptibility in the Turkish population. Now the results need to be confirmed with a larger sample size.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.22 no.2
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• pp.89-96
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• 2022

This paper suggests heuristic algorithm for single-model cross-over assembly line balancing problem that is a kind of NP-hard problem. The assembly line balance problem is mainly applied with metaheuristic methods, and no algorithm has been proposed to find the exact solution of polynomial time, making it very difficult to apply in practice. The proposed bi-directional clustering algorithm computes the minimum number of worker m^* = ⌈W/c⌉ and goal cycle time c^* = ⌈W/m^*⌉ from the given total assembling time W and cycle time c. Then we assign each workstation i=1,2,…,m^* to T_i=c^* ±α≤ c using bi-directional clustering method. For 7 experimental data, this bi-directional clustering algorithm same performance as other methods.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.30A no.7
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• pp.19-25
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• 1993

By using the point matching method, the coplanar waveguide shielded by the rectangular waveguide has been analyzed. The particular potential solution of C.P.W has been obtained from the boundary condition by using the point matching method. The line capacitance has been obtained from the total charge of the center conductor per length. The effective dielectric constant and the line impedance have been obtained from the line capacitance of C.P.W.