• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.11a
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• pp.553-556
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• 2009

In this study, ignition tests of a gas turbine combustor were performed to evaluate an ignition loop at low temperature condition. An experimental setup was constructed to simulate low temperature condition with a heat exchanger using dry ice as a coolant. Various low temperature conditions could be created by controlling the amount of air though the heat exchanger. The results showed that ignition limit decreased with air temperature.

• Nuclear Engineering and Technology
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• v.52 no.3
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• pp.520-529
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• 2020

Experimental investigations were attempted to simultaneously observe the vapor behaviors and critical heat flux under static and rolling conditions. From visualization results, vapor initiated, grew, and detached individually in a vertical direction from the static heated surfaces (at 10, 20, and 30°). While under rolling motion, initiated vapor grew, and interacted with each other, resulting in forming a wider dry spot on the heated surface. Also, it was observed that the vapor drifted upward and stayed on the heated surface longer compared to under static condition. The faster the platform rolls, the longer the vapor stay on the heated surface, significantly decreasing the CHF. On the other hand, as the platform rolls slower (at high rolling period), CHF increases. CHF was decreased with increasing maximum rolling amplitude and inclination angle under both conditions (static and rolling). CHF under rolling conditions was noticed to be lower than under static condition except at maximum rolling amplitude of 10°. The bubble departure frequency at a maximum rolling amplitude of 10° was the highest among all of rolling amplitudes, thereby enhancing the CHF. These results indicate that rolling motion significantly affects vapor behaviors and CHF.

• Electrical & Electronic Materials
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• v.10 no.3
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• pp.217-225
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• 1997

In this study, the PVDF organic thin film was fabricated by the physical vapor deposition method to be dry-process. The distance of heat source and substrate was 5[cm] and the temperature of substrate was 30[.deg. C], when the pressure had reached 2.0 x 10$^{-5}$ [Torr], the temperature of heat source was reached to 285[.deg. C] to heat at 6-8[.deg. C/min] rate, the shutter was opened and deposition was started. TG-DTA(Thermogravimetric-Differential Thermal Analysis) spectrum of PVDF pellets showed that endothermic peak arose at 170[.deg. C] and exothermic peak at 524[.deg. C], but that of thin PVDF film showed that endothermic peak arose at 145[.deg. C] and exothermic peak at 443[.deg C]. The current density was increased linearly with increasing voltage but increased nonlinearly with higher electric field than 250[kV/cm] and activation energy was about 0.667[eV] at the temperature of 30-90[.deg. C].

• Journal of Haehwa Medicine
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• v.11 no.1
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• pp.285-294
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• 2002

The purpose of this study was to find the way of treatment and prevention the stroke by Sasang constitutional medical therapy. I came to get some conclusions after considering literatures of ${\ll}$Dongyi Suse Bowon${\gg}$ and the conclusion as follows. 1. In ${\ll}$Dongyi Suse Bowon${\gg}$ the stroke of Soumin is caused by 'Interior cold disease'. When 'Interior Yin' can not descend, the disease arise. In this case Lee Je-ma used 'Sohabhyang-won(蘇合香元)', 'Chulaek-su(鐵液水)'. 2. The stroke of Soyangin is caused by 'Interior heat disease'. When the hot Qi of stomach and spleen is blocked, the disease arise. In this case Lee Je-ma used 'Dokhwal-jihwang-tang(獨活地黃湯)', 'Jihwang-baekho-tang(地黃白虎湯)'. 3. The stroke of Taeumin is caused by 'Dry and heat disease'. When the heat of liver and the dryness of lung is excessive, the disease arise. In this case Lee Je-ma treated with 'Woohwang-chungsim-hwan(牛黃淸心丸)', 'Wonji-sukchangpo-tang(遠志石菖蒲湯)', and 'Kwache-san(瓜帶散)' etc. Above results indicate that not only taking medicine but also filling up the Healthy energy(保命之主) is important to treat stroke.

• Textile Coloration and Finishing
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• v.25 no.2
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• pp.134-139
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• 2013

A tenter is very important to dry and heat-set fabrics in textile dyeing and finishing industry. However, the tenter machine typically utilizes more than 80% of all the power in dyeing system, and yet is one of the primary machine which affects quality of fabrics. Therefore, performance optimization of the tenter machine is required to reduce energy consumption and enhance quality of fabrics. To optimize the tenter machine, it is important to maintain the uniform flow rate, which can be obtained by optimizing a nozzle geometry. In this study, emboss hole angle was investigated as main parameter in flow rate uniformity and heat flux efficiency. The analysis results were compared with those acquired from bench-scale dryer test in the laboratory. The tenter machine performance simulated by Computational Fluid Dynamics(CFD) was optimized by controlling emboss hole angle.

• The Korean Journal of Food And Nutrition
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• v.33 no.2
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• pp.117-130
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• 2020

The purpose of this study was to compare differences in the main food components of quinoa (Chenopodium quinoa Willd.) cultivated in Hongcheon after steaming, boiling, and roasting. Among the general components, crude protein, fat, and ash content were the highest in raw quinoa. Dry matter and carbohydrate content was the highest in steamed quinoa, while total dietary fiber content was highest in roasted quinoa. Total amino acid contents were the highest in boiled quinoa and lowest in steamed quinoa. Fatty acid content was highest in raw quinoa and lowest in boiled quinoa. The mineral (calcium, potassium, and phosphorus) and vitamin content was most enriched in raw quinoa, while iron, magnesium, zinc, and manganese were highest in boiled quinoa. For free sugars, the fructose and sucrose levels were highest in raw quinoa, while glucose level was highest in roasted quinoa. The water-soluble vitamin and free sugar contents were lowest in boiled quinoa. In summary, nutritional levels of vitamins vulnerable to heat and unsaturated fatty acids decreased after cooking with heat, while those of amino acids and saturated fatty acids increased after cooking with heat, although there were variables based on different cooking methods.

• Transactions of Materials Processing
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• v.15 no.2 s.83
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• pp.112-117
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• 2006

Sliding wear mechanism of a high nitrogen austenitic 18Cr-18Mn-2Mo-0.9N steel has been investigated. Dry sliding wear tests of the steel were carried out at various loads of IN-10N under a constant sliding speed condition of 0.15m/s against AISI 52100 bearing steel balls. Solution ($1050^{\circ}C$) and isothermal aging ($900^{\circ}C$) heat treatments were performed on the steel and the effect of the heat treatments on the wear was investigated. Wear rates of the solution-treated steel specimen remained low until 5N load, and then increased abruptly at loads above 5N. The rates of isothermally aged specimens were low and increased gradually with the applied load. Worn surfaces, their cross sections, and wear debris of the steel specimens were examined with a scanning electron microscopy. Phases of the heat-treated specimen and the wear debris were identified using XRD. The transformed phase underneath a sliding track was investigated and analyzed using a TEM. Effects of the phase transformation during the wear and $Cr_{2}N$ precipitates formed during the isothermal aging on the wear of the austenitic steel were discussed.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2005.10a
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• pp.105-108
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• 2005

Sliding wear mechanism of a high nitrogen austenitic 18Cr-18Mn-2Mo-0.9N steel has been investigated. Dry sliding wear tests of the steel were carried out at various loads of 1N-10N under a constant sliding speed condition of 0.15m/s against AISI 52100 bearing steel balls. Solution $(1050^{\circ}C)$ and isothermal aging $(900^{\circ}C)$ heat treatments were performed on the steel and the effect of the heat treatments on the wear were investigated. Wear rates of the solution-treated steel specimen remained low until 5N, and then increased abruptly at loads above 5N. The rates of isothermally aged specimens were low and increased gradually with the applied load. Worn surfaces, their cross sections, and wear debris of the steel specimens were examined with a scanning electron microscopy. Phases of the heat-treated specimen and the wear debris were identified using XRD. Phases transformed underneath the sliding track during the wear were investigated and analyzed using TEM. Effects of the phase transformation during the wear and $Cr_2N$ precipitates formed during the isothermal aging on the wear of the austenitic steel were discussed.

• Journal of Haehwa Medicine
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• v.13 no.2
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• pp.303-315
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• 2004

1. The acupuncture & moxibustion of hysterorrhea is focussed on bloody uterine discharge, leukorrhea and we must carefully diagnose the etiology & the machanism of disease. 2. The causes of hysterorrhea are dampness, impairment of seven emotion, irregular food intake, excessive intercourse and they are impotantly related to liver, spleen, kidney, the ren channel the chong channel 3. Using external medical treatment for Leucorrhea is washing and fumigation on vagina, to wash vagina, to insert vagina, cleansing theraphy and use with Suppository such as YONGYEOMGO(龍鹽膏), KAMISASANGJASAN(加味蛇床子散), SASANGSACHUNGSEJE(蛇床子洗劑). 4. The efficacy of medicines to use external medical treatment is as follow to helpcirculation of blood, to warm spleen and stomach, to warm blood, to warm uterus and remove cold, to remove heat and dry moisture, to down heat-product, to contract bloodvessel, to counteract poison and destory virus, to make enerey and blood.. 5. The diagnosis is grossly divided into the flowing downward of damp-heat, the weaknessof the qi of the spleen, dificiency of yuan of the kidney and according to the each diagnosis we should select adquate points representing the treatment of cooling(zhongji, yinlingquan, xingjian, etc), desiccation, heiping qi(qihai, zusanli, sanyinjiao, etc), tonificating yang (guanyuan, mingmen, shinshu, etc). 6. The moxibustion is the warming the lower jiao and eliminating the cold, the points are the mingmen point, the zhongji point, the guanyuan point, etc 7. Besides the acupuncture & moxibustion of hysterorrhea, we can make use of acusetor, ear acupuncture, endermosis, dong shi shen fa.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.15 no.7
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• pp.595-603
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• 2003

R407C is considered as an alternative refrigerant to R22 for air conditioners. An experimental investigation was made to study the characteristics of the condensation heat transfer and pressure drop for R407C flowing in a fin-and-tube heat exchanger used for commercial air-conditioning units. Experiments were carried out under the conditions of inlet refrigerant temperature of 6$0^{\circ}C$ and refrigerant mass flux varying from 150 to 250 kg/$m^2$s for refrigerant side. The inlet air has dry bulb temperature of 35$^{\circ}C$ , relative humidity of 50% and air velocity varying from 0.8 to 1.6 m/s. Experiments show that air velocity increased by 25% is needed for R407C than that of R22 for subcooling temperature of 5$^{\circ}C$, which resulted in air-side pressure drop increase of 28.8% for R407C as compared to R22. As a consequence, in order to provide the same design condition of a condenser, the fan requires higher electric-power consumption with R407C than that with R22.