• Nuclear Engineering and Technology
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• v.32 no.1
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• pp.34-45
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• 2000

This study is concerned with the experimental test and numerical analysis of the heat transfer and solidification of the molten metal pool with overlying coolant with boiling. In the test, the metal pool is heated from the bottom surface and coolant is injected onto the molten metal pool. Experiments were performed by changing the test section bottom surface temperature of the metal layer and the coolant injection rate. The two-phase boiling coolant experimental results are compared against the dry test data without coolant or solidification of the molten metal pool, and against the crust formation experiment with subcooled coolant. Also, a numerical analysis is performed to check on the measured data. The numerical program is developed using the enthalpy method, the finite volume method and the SIMPLER algorithm. The experimental results of the heat transfer show general agreement with the calculated values. The present empirical test and numerical results of the heat transfer on the molten metal pool are apparently higher than those without coolant boiling. This is probably because this experiment was performed in concurrence of solidification in the molten metal pool and the rapid boiling of the coolant. The other experiments were performed without coolant boiling and the correlation was developed for the pure molten metal without phase change.

• Nuclear Engineering and Technology
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• v.31 no.1
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• pp.17-28
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• 1999

A thermal-hydraulic analysis is conducted on the loss-of-coolant-accident (LOCA) during shutdown operation of YGN Units 3/4. Based on the review of plant-specific characteristics of YGN Units 3/4 in design and operation, a set of analysis cases is determined, and predicted by the RELAP5/MOD3.2 code during LOCA in the hot-standby mode. The evaluated thermal-hydraulic phenomena are blowdown, break flow, inventory distribution, natural circulation, and core thermal response. The difference in thermal-hydraulic behavior of LOCA at shutolown condition from that of LOCA at full power is identified as depressurization rate, the delay in peak natural circulation timing and the loop seal clearing (LSC) timing. In addition, the effect of high pressure safety injection (HPSI) on plant response is also evaluated. The break spectrum analysis shows that the critical break size can be between 1% to 2% of cold leg area, and that the available operator action time for the Sl actuation and the margin in the peak clad temperature (PCT) could be reduced when considering uncertainties of the present RELAP5 calculation.

• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.1161-1166
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• 2008

The objective of this research was to investigate the enhancement of heat transfer by mesh in water/air direct contact air conditioning system. Mesh is inserted as a turbulent promoter in front of the water injection nozzle. The heat transfer characteristics with and without mesh and the effect of the number of inserted mesh and mesh porosity size have been studied experimentally. Inserted mesh improves heat transfer efficiency compared to non-inserted mesh system and heat transfer efficiency increased as the number of mesh is increased. Meanwhile, heat transfer efficiency decreased as the porosity of the mesh is increased. With inserted mesh, inlet and outlet temperature difference of air increased more than 50%. Heat exchange time of water/air to reach the 100% humidity decreased less than 30%. This result shows inserted mesh can enhance the performance of the water/air direct contact air conditioning system.

• Journal of Haehwa Medicine
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• v.10 no.1
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• pp.167-174
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• 2001

According to the literatual study on the external treatment of premature ejaculation, the results were as follows. 1. Linition is inunction glans penis after infiltrate ASARI HERBA CUM RADICE(細辛), CARYOPHYLLI FLOS(丁香), CHEBULAE FRUCTUS(訶子), PAPAVERIS FRUCTUS(罌粟殼), FOSSILIA OSSIS MASTODI(龍骨), OSTREAE CONCHA(牡蠣 in oenostagma. 2. Retrojection or hypoatmism method is boiling CHINENSIS GALLA(五倍子), CNIDII FRUCTUS(蛇牀子) and hypoatmism, down temperature infiltrate glans penis. 3. Mesompharion apposition method is calorization VESPAE NIDUS(露蜂房), ANGELICAE DAHARICAE RADIX(白芷), and utilization vineger apposite mesompharion. 4. Medicament belt method is belt on lumbus and bythus by ROSAE LAEVIGATAE FRUCTUS(金櫻子), EURYALES SEMEN, OSTREAE CONCHA(牡蠣), TRIBULI FRUCTUS, AIPINIAE OXYPHYLLAE FRUCTUS(益智仁), NELUMBINIS SEMEN(蓮子肉) Powders. 5. Enema is injection in the rectum ANGELICAE GIGANTIS RADIX(當歸) effusion. 6. Much utilization agent are ASARI HERBA CUM RADICE(細辛), CHINENSIS GALLA(五倍子), OSTREAE CONCHA(牡蠣), CNIDII FRUCTUS(蛇床子), GRANATI PERICARPIUM(石榴皮), CARYOPHYLLI FLOS(丁香), CHEBULAE FRUCTUS(訶子), FOSSILIA OSSIS MASTODI(龍骨), VESPAE NIDUS(露蜂房), PAPAVERIS FRUCTUS(罌粟殼) etc. They are occupied in adstringentia, juventia, divergence agent, liver stabilizer agent.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.381-381
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• 2011

The influence of the water vapor on the growth of single-walled carbon nanotubes (SWCNTs) was investigated. SWCNTs were synthesized by catalytic chemical vapor deposition of acetylene over Fe-Mo/MgO catalyst with injection of water vapor. The morphologies and structures of the water-assisted SWCNTs were investigated according to the growth conditions such as water vapor concentrations, flow rate of the gas, furnace temperature, and growth time. Water-assisted SWCNTs exhibited large bundle morphological features with well-alignment of each CNT, while SWCNTs synthesized in the absence of water vapor showed entangled CNT with the random orientation. We also found that the diameter of the SWCNT bundle could be controlled by the growth condition. In our optimal growth condition, the product yield and the purity were 300 wt. % and 75%, which were 7.5 and 2.5 times higher than those of SWCNTs synthesized without water vapor, respectively. More detail discussion will be offered at the poster presentation.

• Macromolecular Research
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• v.13 no.5
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• pp.403-408
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• 2005

A new terphenylenevinylene carbazylenevinylene alternating copolymer with the advantage of poly(p-phenylenevinylene) (PPV), poly(p-phenylene )(PPP) and poly(carbazole) was designed, synthesized and characterized. The polymer structure was confirmed by various spectroscopic analyses and the number average molecular weight ($M_n$) of the obtained polymer was 7,800. The resulting polymer was thermally stable with high glass transition temperature ($T_g$) ($150^{\circ}C$), and was readily soluble in common organic solvents. Cyclic voltammetry study revealed that the HOMO and LUMO energy levels of the polymer were 5.37 and 2.47 eV, respectively. The ITO/PEDOT/polymer/AI device fabricated from the polymer emitted bright sky blue light with a maximum peak of around 478 nm. The device showed the maximum brightness of 1,200 nW with a turn-on voltage of 7V.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.17 no.3
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• pp.8-17
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• 2004

Objective: Under recognition of the similarity between carbuncle in Oriental medicine and inflammatory disease, NeiShuHuangLianJang(N.H.) has been used as an antiphlogistic agent. The present reports shows the anti-inflammatory effects of N.H. Method: Experimental animals made use of 4-5 weeks age(weight 20-25g) ICR(male)mouse. They were farmed individually in a temperature($22{\pm}0.5{\circ}$) and light(06:00 to 18:00 h) controlled room with free access to water and food. The N.H.(1.0g／kg, 3.0g／kg) extracted from NeiShuHuangLianTang were administered intragastrically prior to LPS I.P injection. we measured WBC count, IL-6 level in plasma and TNF-${\alpha}$ level in plasma. Result : 1. N.H. suppressed inflammatory reaction induced by LPS. 2. N.H. suppressed WBC count in inflammatory reaction induced by LPS. 3. N.H. suppressed 1L-6 level in inflammatory reaction induced by LPS. According to above experiments, N.H. was improved its suppression effect against the inflammatory reaction through WBC count and IL-6 level. So N.H. which is used for the inflammatory disease(carbuncle) in Oriental Medicine is assumed to have a curative effects against this disease by controlling WBC count and IL-6 level in plasma.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2007.10a
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• pp.100-103
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• 2007

A microlens array has been required to improve light conversion efficiency in image sensors. A microlens array can be usually fabricated by photoresist reflow, hot-embossing, micro injection molding, and UV-imprinting. Among these processes, a UV-imprinting, which is operated at room temperature with relatively low applied pressure, can be a desirable process to integrate microlens array on image sensors, because this process provides the components with low thermal expansion, enhanced stability, and low birefringence, furthermore, it is more suitable for mass production of high quality microlens array. In this study, to analyze the optical properties of the wafer scale microlens array integrated image sensor, another wafer scale simulated image sensor chip array was designed and fabricated. An aspherical square microlens was designed and integrated on a simulated image sensor chip array using a UV-imprinting process. Finally, the optical performances were measured and analyzed.

• Journal of Wetlands Research
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• v.16 no.2
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• pp.275-280
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• 2014

Because ammonia in water body can cause water pollution as a result of generating ammonium ion, it is of importance in the management of water quality. This work performed to analyze the ammonium ion by measuring the color band length on the basis of modifying the indophenol method. When 1-naphthol was employed as a coloring agent, the maximum absorbance was shown near 720nm, where the proper injection was in the range of 0.5-1.5ml. About 80% of absorbance was observed after the color development was made within the 20 minutes. In the manufacturing of coloring agent, the proper concentration of NaOH was 1.5-2.5M, and the effect of pH on the color development is negligible. In addition, the color development was effectively in the region of room temperature.

• Journal of the Korean Society of Combustion
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• v.14 no.4
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• pp.17-24
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• 2009

Reburning is one of the most useful technologies for reducing nitric oxide in economically and technically. The reburning process was demonstrated as an effective NOx reduction method through injection of a secondary hydrocarbon fuel. An experimental study has been conducted to evaluate the effect of biomass reburning on NOx and CO formation in a light oil flamed combustion furnace. Reburning tests on NOx reduction of air-carried rice husk powder as the reburn fuel and light oil as the main fuel were performed in flames stabilized by a co-flow swirl and fuel staged burner, which was mounted at the front of the furnace. The results included flue gas emissions and temperature distribution in the furnace for several kinds of experimental conditions. It was observed clearly that NOx concentrations in the exhaust have considerably decreased due to effect of biomass reburning. The maximum NOx reduction rate was 42% when the reburn fuel fraction was 0.18. The CO emissions were kept under 42 ppmv in all experimental tests. And this paper makes clear that in order to decrease NOx concentration in the exhaust when the biomass reburning system is adapted, the control of some factors such as reburn fuel fraction and reburn zone fraction is very important.