• Korean Chemical Engineering Research
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• v.59 no.2
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• pp.260-268
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• 2021

Adsorption is the most promising technology used to adsorb CO2 to reduce its concentration in the atmosphere due to its functional effectiveness. Various porous materials have been extensively synthesized to boost CO2 adsorption efficiency, for example, zeolite. Here, we report the synthesis process of zeolite adsorbent impregnated with amine, combining the benefit of these two substances. We compared conventional heating with microwave-assisted heating by varying concentrations of monoethanolamine in methanol (10% v/v and 40% v/v) as a liquid solution. The results showed that monoethanolamine impregnation helps significantly increase adsorption capacity, where adsorption occurs as a physisorption and not as chemisorption due to the adsorbent's steric hindrance effect. The highest adsorption capacity of 0.3649 mmol CO2 / gram adsorbent was reached by microwave exposure for 10 minutes. This work also reveals that a decrease in CO2 adsorption capacity was observed at a longer exposure period, and it reached a constant 40-minute adsorption rate. Impregnating activated zeolite with 40% monoethanolamine for 10 minutes in addition to microwave exposure (0.8973 mmol CO2 / gram adsorbent) is the maximum adsorption ability achieved.

• Journal of Korea Society of Waste Management
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• v.35 no.8
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• pp.701-708
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• 2018

Chemical batch tests were conducted to investigate the amount of nutrients that were released from the wasted activated sludge during microwave heating. For this study, three types of activated sludge were obtained from $A_2/O$, MLE and oxidation ditch (OD) processes. Polyphosphate-accumulating organisms in the activated sludge have a unique trait: they releases phosphate from the cell when they are exposed to high temperatures. The sludge obtained from the $A_2/O$ process released the largest amount of phosphate, followed by those from the MLE and OD processes. The release of phosphate increased with increasing polyphosphate content in the sludge under strongly alkaline or acidic conditions. Furthermore, ammonia and heavy metals were released with phosphorous. The largest amount of ammonia was observed from the sludge obtained from the MLE process. The release of heavy metals strongly depends on the pH conditions. Therefore, the chemical analysis results strongly suggest that both phosphorus and ammonia react with $Mg^{2+}$ or $Ca^{2+}$ to form metal complexes such as magnesium ammonium phosphate or hydroxyapatite under alkaline conditions.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.84-89
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• 2003

Fuzzy controller is one of the succeed controller used in the process control in case of model uncertainties. But it my be difficult to fuzzy controller to articulate the accumulated knowledge to encompass all circumstance. Hence, it is essential to provide a tuning capability. There are many parameters in fuzzy controller can be adapted, scale factor tuning of normalized fuzzy controller is one of the adaptation parameter. Two adaptation methods are implemented in this work on an experimental thermal process, which simulate heating process in liquefied petroleum gases (LPG) recovery process in one of petrochemical industries: Gradient decent (GD) adaptation method; supervisory fuzzy controller. A comparison between the two methods is discussed.

• Journal of Pharmacopuncture
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• v.13 no.2
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• pp.33-49
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• 2010

Objectives: The aim of this experiment is to provide an objective differentiation of cultivated ginseng, mountain ginseng through component analysis, and to know the change of gin senoside components in the process of heating and fermentation Methods: Comparative analyses of ginsenoside $Rb_1$, $Rb_2$, Rc, Rd, Re, Rf, $Rg_1$, $Rg_3$, $Rh_1$, and $Rh_2$, from the cultivated ginseng 4 and 6 years, and mountain cultivated ginseng were conducted using HPLC (High Performance Liquid Chromatography, hereafter HPLC). And the same analyses were conducted in the process of heating and fermentation using mixed Lactobacillus rhamnosus, Lactobacillus plantarum, Bifidobacterium lactis for 7 days. Results: The change of ginsenosides to the process of red ginseng and fermentation, cultivated ginseng and mountain cultivated ginseng were showed another results. Mountain ginseng showed a lot of change compared with cultivated ginsengs. In the 7 days of fermentation, mountain ginseng showed that ginsenoside $Rg_1$, $Rb_1$, $Rb_2$, Rc, and Rd were decreased and increased ginsenoside Re, Rf, $Rg_3$ and $Rh_1$ were increased compared with cultivated ginseng Conclusions: It seemed that ginsenosides of mountain cultivated ginseng was better resolved than cultivated ginseng because the difference of structure or distribution of ginsenosides in the condition of fermentation.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.6
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• pp.477-482
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• 2017

When using the FDM to create a 3D object, a thermoplastic filament is heated to its melting point and then extruded layer by layer. Although the FDM printing process has many advantages, its accuracy, and surface finish are not satisfactory. In recent years, much research has been devoted to improving the accuracy of the FDM printing process. The temperature difference between the nozzle and the interior of the chamber of a 3D printer is one of the important parameters affecting the printing process. In this study, we propose a methodology to reduce this temperature difference through design improvement. In addition, we elucidate how this design improvement affects product quality. The FDM printing process is conventionally carried out in a closed chamber. However, in this study, an open heating system is used to reduce the temperature. The FDM printing processes were simulated using FEM analysis.

• Journal of Fashion Business
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• v.16 no.1
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• pp.69-82
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• 2012

This thesis aimed to reduce the differences of hair color when hair coloring, so it researched the differences & changes in hair color before shampoo v.s. after shampoo and dry on different heat processes when acid hair color dyeing. Five hair color dyes (Y, R, B, G, Br) manufactured by two different corporations were used. The acid hair color dyes were tinted on black and bleached hair pieces subjected to 3 different heat process; 1. Normal Temperature($25^{\circ}C$, 30min.) / 2. Heating($40^{\circ}C$, 15min.)+Normal Temperature($25^{\circ}C$, 15min.) / 3. Heating($40^{\circ}C$, 30min.). Color numbers were divided by NCS value, chroma, and hue. Statistical averages were derived and t-test was conducted using SPSS V12. Hair color differences and changes were drawn on an NCS chart using Photo Shop PS. The conclu is; If acid hair colorings are separated by a heating process, hair value & chroma change before shampoo vs. after shampoo & dry regardless of the color of hair and the heat process. Hue is not changed or shifted counter clockwise NCS color circle, but some exceptions, and it's the same when the total heat process results are combined. Black hair's value shifted downward and chroma left, and hue stayed either neutral or one color or it shifted counter clockwise on NCS color circle. Bleached hair's value shifted upward and chroma right, and hue stayed one color or shifted counter clockwise, but some exceptions. And it can be shown on NCS chart.

• Transactions of Materials Processing
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• v.32 no.5
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• pp.239-246
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• 2023

To reduce the forming load due to the temperature drop, during the hot forging process, a reheating hot forging process design is required that to repeat heating and forging. However, if the critical strain required for recrystallization is not induced during forging and grain growth becomes dominant due to the reduction in dislocation density due to repeated heating, the mechanical properties may deteriorate. Therefore, in this study, Inconel 706 alloy was applied, and the grain refinement behavior was comparatively analyzed according to the number of reheating times and effective strain during reheating hot forging process. Reheating was carried out with a total compression rate of 40% up to 4 times. The Inconel 706 compression test specimens heated once showed finer grains as the effective strain increased due to the dynamic recrystallization phenomenon. However, as the number of heating increases, grain refinement was observed even in a low effective strain distribution of 0.43 due to static recrystallization during reheating. Moreover, grain growth occurs at a relatively low effective strain of 0.43 when the number of reheating is four or more. Therefore, it was effective to apply an effective strain of 0.43 or more during hot forging to Inconel 706 in order to induce crystallization through grain refinement and improve the properties of forged products. In addition, we could notice that up to three reheating times condition was appropriate to prevent grain growth and maintain fine grain size.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.817-820
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• 2001

This machine is a high-vacuum exhaust sealing device which makes the inside of PDP element in high vacuum state, blows inactive gases into it and finally seals it. This machine consists of vacuuming parts, heating parts and exhausting parts. Applying the energy saving technology, this machine improves the temperature uniformity of vacuuming and heating parts.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.06a
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• pp.399-400
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• 2008

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.441-442
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• 2003

복잡한 지형에서 국지적인 순환에 의한 에너지 교환은 기상변화에 중요한 역할을 담당한다. 종관장이 영향이 약하고 양호한 기상조건 하에서 대기 경계층내에서의 온도와 바람장은 국지적인 순환에 영향을 받는다(Kawamura,1979; Kuwagata et al.,1990; Winston et al.,1992). 즉 이러한 기상 조건 하에서는 중규모 순환에 의해 에너지의 수송효과가 크고 각기 수송된 에너지에 의해서 지역별로 대기 경계층내의 가열율에도 차이가 나타난다. (중략)