• Korean Journal of Materials Research
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• v.4 no.3
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• pp.364-375
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• 1994

The microstructure of medium-carbon non-heat treated steels by air-cooling shows ferritepearlite structure. Compared to the conventional Q/T steels, the strength of these steels containing V, Nb and Ti are similar to Q/T steels. However, their toughness are inferior. In this study, the mechanical properties and microstructures of low-carbon Mo bearing steels produced by direct-quenching process were investigated. Especially, the effect of Mo on the direct-quenched steels was examined. The direct-quenched steels containing Mo were found to have higher strength and toughness. Mo seemed to be effective in producing the fine structure and dense precipitates because of decreasing transformation temperature. The best results were 1211 MPa in UTS and 127.5 J in toughness in the oil quenched 0.15C+O.llV+ 0.035Nb+ 1.81Mo steel. Compared to 0.4% C microalloyed steels, this results showed that UTS increased by 45% and toughness by 2 times.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2005.06a
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• pp.426-427
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• 2005

Advanced Spent Fuel Conditioning Process (ACP) is a pyrochemical process in which the spent fuel of PWR is transformed into the uranic metal ingot. Through this process, which has been developed in KAERI since 1998, the radioactivity, the radiotoxicity, the heat and the volume of the PWR spent fuel are reduced by a quarter of the original. To demonstrate a lab-scale process and extract the data for the later pilot-scale process, a demonstration facility of ACP (ACPF) is under construction and the lab-scale demonstration is slated for 2006. To establish the safeguardability of ACPF, a safeguards system including a neutron counter based on non-destructive assay, which is named as ACP Safeguards Neutron Counter (ASNC), the ACP Safeguards Surveillance System (ASSS) which consists of two neutron monitors and five IAEA cameras, and Laser Induced Breakdown System (LIBS) have been developed and are ready to be installed at ACPF. The target materials of ACP to assay with ASNC are categorized into three types among which the first is the uranic metal ingot, the second is the salt waste and the last is $UO_2$ and $U_{3}O_8$ powders, rod cuts and hulls. The Pu content of process nuclear materials can be accounted with ASNC. The ASSS is integrated in the ACP Intelligent Surveillance Software (AISS) in which the IAEA camera images and background signals at the rear doors of ACPF are displayed. The composition of special nuclear materials of ACP can be measured with LIBS which can be a supporting measurement tool for ASNC. The conceptual picture of safeguards system of ACPF is shown in Fig. 1.

• Korean Journal of Acupuncture
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• v.36 no.4
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• pp.210-220
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• 2019

Objectives : Warm needling is a combined treatment technique of acupuncture and moxibustion. In this study, we aimed to find out the components related with the thermal stimulation of the warm needling and to provide basic data for the guideline of the warm needling technique in the clinic. Methods : In this study, we measured thermal change of 3% agarose phantom embedding K-type thermocouples in depths of 0, 1, 2, 4, 8 and 16 mm. The warm needling was performed with acupuncture needles of various specifications (0.50×30, 0.50×40, 0.30×30, 0.30×40, 0.20×30 and 0.20×40 mm). A linear regression analysis was performed to find out the major component and quantify the effectiveness of the thermal stimulation during warm needling. Results : As a result of the measurement of temperature change, we could observe the thermal change pattern from the surface of the phantom to the 16mm deep part of the phantom. The thermal pattern was similar among the needles of different specifications. The regression analysis pointed the distance between the moxa cautery and the skin surface as the main component for the thermal stimulation of the warm needling. Conclusions : The authors suggest considering the distance between moxa cautery and the skin rather than the diameter of the acupuncture needle in accordance to the result of the study.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.27 no.5
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• pp.397-403
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• 2001

Purpose: The purpose of this study was to evaluate the postoperative stability of LeFort I osteotomy in two-jaw surgery of skeletal class III malocclusion and to help the establishment of treatment planning in patients with a skeletal class III malocclusion in the future. Materials and Methods: The lateral cephalograms of 14 patients who had been underwent two-jaw surgery via one-piece LeFort I osteotomy were traced and the landmarks were identified. Repeated tracings and construction of reference planes were done. Comparisons were made from the immediate postoperative to late postoperative results of each landmarks on the horizontal and vertical directions. Conclusions: 1. The horizontal changes of landmark ANS, point A, PNS and Mx6Rt between immediate postoperative to late postoperative data were statistically insignificant(p>0.05). 2. The vertical changes of landmark ANS, point A, PNS, Mx6Cr and Mx6Rt between immediate postoperative to late postoperative data were statistically insignificant(p>0.05). 3. The horizontal change of landmark Mx6Cr between immediate postoperative to late postoperative data was statistically significant(p<0.05). 4. Results showed that it was stable that one-piece LeFort I osteotomy in two-jaw surgery of skeletal class III malocclusion.

• Journal of Sasang Constitutional Medicine
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• v.10 no.1
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• pp.311-341
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• 1998

The objective of this article is to induce that the conception of 'Qi-jul(氣質) and Qi-pum(氣稟)' was introduced to the Sasang(四象) Constitutional Medicine from bibliographic study on the theory of 'Qi-pum(氣稟)'. The conclusions summerized as followings. 1. In the oriental medicine, qualitative difference of 'zheng-qi(正氣)' among the individuals, the opposing power against a disease, is regarded as constitution. Having been used as 'nature(素)', 'quality(質)' and 'character(氣質)' in the oriental medical book, the word of 'Che-Jil(體質)' was used in good earnest at the end of 'Qing(情)' dynasty. 2. The nature(性) is divided into two, original nature(本然之性) and charicteristic nature(氣質之性) in the 'New confucianism(新儒學)' and the former means a principle(理), is a pure and good thing and used as a conception of universality, the latter is a principle of character and a imperfect imitation of principle(理). 3. It was repeatedly confirmed that 'Qi-jil and Qi-pum' meant the difference among the individuals by the dispute of 'Li-Qi(理氣)' caused by Lee Hwang(李滉) and Lee Yi(李耳) and by that of 'Ho-Rak(湖洛)' in the Ch'o-son(朝鮮) dynasty. 4. Han Sok-Ji, based on Meng-Zi(孟子)'s doctrine that man's inborn nature is good, criticized the theory of 'Qi-pum' which was 'Zhu-Zi(朱子)'s opinion and his opinion about the life(命) was thought to clue to the classification of the 'Sasang(四象)' invented by Lee Je-Ma as Park Se-Dang's theory that everyone has common nature but has different life(命). 5. By introducing the theory of 'Qi-pum' and the conception of life(命) which was understood as a special character by Han Sok-Ji and Park Se-Dang to Sa-sang constitutional medicine, Lee Je-Ma explained the reason why each man who was classified four constitutions, 'Taiyang'(太陽), 'Taiyin'(太陰), 'Shaoyang'(少陽), 'Shaoyin'(少陰), had the different formation of the visceral department(臟局).

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.323-323
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• 2013

High power light-emitting diodes (LEDs) are widely used in many device applications due to its ability to operate at high power and produce high luminance. However, releasing the heat accumulated in the device during operating time is a serious problem that needs to be resolved to ensure high optical efficiency. Ceramic or Aluminium base metal printed circuit boards are generally used as integral parts of communication and power devices due to its outstanding thermal dissipation capabilities as heat sink or heat spreader. We investigated the characterisation of electroless plating of Ni-B film according to plating bath temperature, ranging from $50^{\circ}C$ to $75^{\circ}C$ on Ag paste/anodised Al ($Al_2O_3$)/Al substrate to be used in metal PCB for high power LED packing systems. X-ray diffraction (XRD), Field-Emission Scanning Electron Microscopy (FE-SEM) and X-ray Photoelectron Spectroscopy (XPS) were used in the film analysis. By XRD result, the structure of the as deposited Ni-B film was amorphous irrespective of bath temperature. The activation energy of electroless Ni-B plating was 59.78 kJ/mol at the temperature region of $50{\sim}75^{\circ}C$. In addition, the Ni-B film grew selectively on the patterned Ag paste surface.

• The Journal of Natural Sciences
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• v.14 no.1
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• pp.7-24
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• 2004

We found new type of thiol peroxidase, fused with GRX.(TPx-GRX) The TPx-GRX exists in pathogenic bacteria including -. This protein was homogeneously purified from the E.coli recombinant overexpressing TPx-GRX. In the presence of a thiol-containing electron donor such as DTT, the purified TPx-GRX has potent the antioxidant to prevent the inactivation of GS by the MCO system, which is comprised of DTT, $Fe^{3+}$, and $O^2$. The antioxidant activity is much higher that other thiol peroxidase. The investigate the peroxidase activity of TPx-GRX, we directly measured the peroxidase activity of TPx-GRX toward peroxides in terms of the removal of peroxides in the presence of GSH. This result demonstrates that the peroxidase activity of TPx-GRX. These taken together results suggest that TPx-GRX is a new member of thiol peroxidase. These observations also suggest that in the pathogenic bacteria, TPx-GRX plays an important antioxidative role as a multiple array defence mechanism against oxidative stress.

• Archives of Pharmacal Research
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• v.25 no.2
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• pp.191-196
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• 2002

The water extract from the root bark of Cortex Mori (CM, Morus alba L.: Sangbaikpi), a mulberry tree, has been known in Chinese traditional medicine to have antiphlogistic, diuretic, and expectorant properties. In this study, the cytotoxicity of CM against tumor cells and its mechanism was examined . CM exhibited cytotoxic activity on K-562, B38O human leukemia cells and B16 mouse melanoma cells at concentrations of > 1 mg/ml. A DNA fragmentation, PARP cleavage, and nuclear condensation assay showed that those cells exposed to CM underwent apoptosis. The water extract of Scutellarie Radix (SR) was used as a negative control and showed no cytotoxicity in those cells. The flow cytometric profiles of the CM-treated cells were also indicative of apoptosis. However, they did not appear to exert the G1 arrest, which is observed in other tubulin inhibitor agents such as vincristine, taxol. The protein-binding test using Biacore and a microtubule assembly-disassembly assay provided evidence showing that CM bound to the tubulins resulting in 3 markets inhibition of the assembly, but not the disassembly of microtubules. The possible nonspecific effect of the CM extract could be excluded due to the results using SR, which did not affect the assembly process. Overall, the water extract of CM induces apoptosis of tumor cells by inhibiting microtubule assembly.

• Journal of the Korean Ceramic Society
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• v.52 no.5
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• pp.299-303
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• 2015

The electrolyte is an important component in determining the performance of Fuel Cells. Especially, investigation of the conduction properties of electrolytes plays a key role in determining the performance of the electrolyte. The electrochemical properties of Yttrium stabilized zirconia (YSZ) were measured to allow the use of this material as an electrolyte for solid oxide fuel cells (SOFC) in the temperature range of $700-1000^{\circ}C$ and in $0.21{\leq}pO_2/atm{\leq}10^{-23}$. A Hebb-Wagner polarization experimental cell was optimally manufactured; here we discuss typical problems associated with making cells. The partial conductivities due to electrons and holes for 8YSZ, which is known as a superior oxygen conductor, were obtained using I-V characteristics based on the Hebb-Wagner polarization method. Activation energies for holes and electrons are $3.99{\pm}0.17eV$ and $1.70{\pm}0.06eV$ respectively. Further, we calculated the oxygen ion conductivity with electron, hole, and total conductivity, which was obtained by DC four probe conductivity measurements. The oxygen ion conductivity was dependent on the temperature; the activation energy was $0.80{\pm}0.10eV$. The electrolyte domain was determined from the top limit, bottom limit, and boundary (p=n) of the oxygen partial pressure. As a result, the electrolyte domain was widely presented in an extensive range of oxygen partial pressures and temperatures.

• Korean Journal of Community Nutrition
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• v.11 no.6
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• pp.808-813
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• 2006

Until now, South Korea does not have either fortification or enrichment program as intervention tools although the addition of micronutrients to foods is for the most part not regulated. The aim of this study was to determine which scenario would most effectively reduce the proportion of the population with low iron intake while not putting other population groups at risk of excessive intakes. In order to investigate potential dietary consequences of iron fortification we analyzed 2 day dietary record data (n=3,955) from the 2001 National Nutrition Surveys. The Proportion of the population consuming dietary iron less than the estimated average requirement (EAR) ranged from $12.4{\sim}87.5%$ depending upon gender and age group. Iron fortification at the level of 100% of Recommended Intake (RI) per 100g to breads and instant o. dried noodles was estimated to result in a 15% decrease of proportion of those with iron less than EAR, while putting 1.4 % of the population greater than the Upper Limit (UL). Iron fortification appeared to be the most effective for the $15{\sim}19$ year old age group, showing 39% reduction of iron intake insufficiency. The results suggest that carefully designed fortification or enrichment to staple foods may contribute to increase dietary iron intakes of Koreans, especially for the young population with a high prevalence of iron inadequacy. As the estimation in this study was based solely upon dietary intake data, iron intake from supplements should be considered in further studies.