• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2017.05a
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• pp.148-148
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• 2017

Surface modification is a type of mechanical manipulation skills to achieve extensive aims including corrosion control, exterior appearance, abrasion resistance, electrical insulation and electrical conductivity of substrate materials by generating a protective surface using electrical, physical and chemical treatment on the surface of parts made from metallic materials. Such surface modification includes plating, anodizing, chemical conversion treatment, painting, lining, coating and surface hardening; this study conducted cavitation experiment to assess improvement of durability using anodizing. In order to observe surface characteristics with applied current density, the electrolyte temperature, concentration was maintained at constant condition. To prevent hindrance of stable growth of oxide layer due to local temperature increase during the experiment, stirring was maintained at constant speed. In addition, using galvanostatic method, it was maintained at processing time of 40minutes for 10 to $30mA/cm^2$. The cavitation experiment was carried out with an ultra sonic vibratory apparatus using piezo-electric effect with modified ASTM-G32. The peak-to-peak amplitude was $30{\mu}m$ and the distance between the horn tip and specimen was 1mm. The specimen after the experiment was cleaned in an ultrasonic bath, dried in a vacuum oven for more than 24 hours, and weighed with an electric balance. The surface damage morphology was observed with 3D analysis microscope. As a result of the study, differences were observed surface hardness and anti-cavitation characteristics depending on the development of oxide film with the anodizing process time.

• Food Science and Preservation
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• v.10 no.1
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• pp.70-74
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• 2003

The distribution of mesophilic and thermophilic bacteria in milled rice was not different according to growing land and variety of rice. However, The number of these bacteria were abundant in milled rice of lower milling degree or longer storage period. The growth of thermophilic bacteria in cooked rice of electric rice cooker was rapidly increased during storage of lower temperature below 75 $^{\circ}C$. Thermophilic bacteria were not appeared just after cooking. After cooked rice was stored far 18∼24 hon thermophilic bacterial growth was rapidly increased by changing spore to vegetative cell. The positive relation between cell number of thermophilic bacteria and occurrence of off-odor was slightly observed. The number of thermophilic bacteria in upper cooked rice of oven and was higher than those in inner and lower cooked rice. Major volatile compound of milled rice cooked and stored in electric rice cooker was hexanal oriented from rice. After long storage, it was confirmed that furan was major volatile compound as off-odor.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.18 no.4
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• pp.1-11
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• 2022

In this study, the thermal runaway of NCM and LFP batteries were compared and analyzed through numerical analysis under various conditions. Comparing the thermal runaway of the NCM622 (18650) battery cell and the LFP (18650) battery cell through oven test simulation, the LFP battery did not show thermal runaway, whereas the NCM622 battery temperature increased to 710℃ in 12 minutes. To observe the thermal runaway and propagation of the prismatic LFP battery cell, the internal temperature was set at 200℃ and the oven test simulation was conducted. It was found that thermal runaway occurred at 391℃ after 47 minutes. As a result of observing thermal runaway propagation by placing five NCM622 and LFP battery cells, the thermal runaway propagation was clearly observed in the case of the NCM622 battery, but in the case of the LFP battery, thermal runaway was not observed after the first cell. From the third battery cell, it was confirmed that the temperature change was very insignificant, and through this, it is considered that the LFP battery is relatively safe compared to the NCM battery in terms of the thermal runaway propagation of the battery.

• Journal of the Korean Ceramic Society
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• v.34 no.9
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• pp.935-940
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• 1997

This study investigated the crystallization behavior in PbO-ZnO-B2O3-TiO2 system sealing glass, inorganic polymer heat-treated by conventional heat and microwave energy. After determining heat-treated temperature for crystallization and characteristic points by DTA analysis, samples were heat-treated in a classical electric furnace and a home-style microwave oven (LG Electronic Co., 2.45 GHz, 700 W). A microwave heat-treated sample had the growth of PbTiO3 crystal at 45$0^{\circ}C$, 2$0^{\circ}C$ lower than that of a conventionally heat-treated sample. Also, it had crystallinity about 20% higher than the conventionally heat-treated sample. At 49$0^{\circ}C$, the size of PbTiO3 crystal in the conventionally heat-treated sample was larger than that in the microwave heat-treated sample due to longer heat-treated time.

• Journal of Korean Society for Quality Management
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• v.31 no.4
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• pp.226-238
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• 2003

Recently, The problems with which our country's company is confronted for business of manufacturing goods. This study set the hypothesis to develop the method that was analysis and application of A reliability evaluation method of environmental material for circuit components in Computer, Color TV, Monitor, Microwave oven, Electric Refrigerator, Automobile parts, other goods. Especially, this study emphasis on regulate export of the EU and North America that it's a environmental material's hazards problem. In this process, this study set the pattern of practical application. Therefore, this study emphasis on the application of A reliability evaluation method of environmental material and the use of other parameters by environmental reliability test data. The result of this study is as follows. 1) There is relationship between regulate material and technical protecting system. 2) Characteristics of hazard materials is operating a healthcare damage factor as well as regulate environmental factors.

• Proceedings of the Korean Society for Quality Management Conference
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• 2007.04a
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• pp.362-369
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• 2007

This study set the hypothesis to develop the method that was analysis and application of a reliability evaluation method of environmental material for the Computer, Color TV, Monitor, Microwave oven, Electric Refrigerator, Automobile parts, other goods. RoHS management and product reliability ensure method for the conservation of environment. Especially, this study emphasis on regulate export of the EU and North America that it's a environmental material problem. Therefore, this study emphasis on the application of a reliability ensure method of environmental material and the use of other parameter by environmental reliability test data. The result of this study is as follows. 1) There is relationship between regulate material and technical protecting system. 2) Characteristics of hazard material is operating a healthcare damage factor as well as regulate environmental factors.

• 제어로봇시스템학회:학술대회논문집
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• 1987.10b
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• pp.492-496
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• 1987

The testing philosophy and control schemes are investigated and applied to construct the Automatic Microwave Leakage Inspection System (AMLIS) . AMLIS is consists of three major parts such as Material Handling Mechanism, Fine Positioning Mechanism and Scanning Mechanism. The material Handling unit is designed to perform loading and unloading microwave oven onto the testing point by pneumatic cylinder and vacuum pump. The Fine positioning part includes X-Y-.THETA. table and distance sensing equipment. The scanning part is composed of five SCARA robots, which traverse X-Y-Z catesian coordinates respectively. The leakage testing probes are placed at the end of this each robot then the path and speed are both controlled via microprocessors. A performance test of this system combined with electric parts and software is done and the basic major function of system are accomplished.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11b
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• pp.61-64
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• 2001

This study relates to a method for manufacturing a solid electrolytic capacitor using a functional polymer composition. The method comprises immersing the rolled aluminum electrolytic capacitor device in polyaniline solution with high electric conductivity to impregnate the device with polyaniline, drying the impregnated device in a drying oven which is maintained at constant temperature to fully remove the solvent, inserting the dried device to a capacitor aluminum can and then sealing with epoxy resin, to manufacture a solid electrolytic capacitor using a conducting polymer. As such, the impregnation can be performed well at not only normal temperature and pressure, but also high temperature and reduced pressure. The solid electrolytic capacitor has the advantages of high capacity, low impedance and low ESR, and also, low manufacturing cost, simple processes and high reliability.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.10 no.3
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• pp.145-149
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• 1977

Thermal resistance of dried bacterial spores against dry heat was determined. Spare suspensions of Bacillus subtilis var. niger ATCC 9372, Bacillus stearothermophilus Oxoid Code BR 23 and Clostridium sporogenes ATCC 19404 were located on aluminium strips, dried in electric oven under vacuum at room temperature for 10 minutes. The aluminium strips were laid in the middle of gas flow (hot air and superheated steam) with the velocity of 6 m/sec and heated at $120^{\circ}C$ for 180 seconds. The calculated D-values showed that there were no remarkable differences in the heat resistance of bacterial spares between $R.H.\leqq0.012$ and R. H.=0.51. Furthermore the thermal resistance of B. subtilis spores to dry heat was greater than that of B. stearothermophilus.

• Proceedings of the IEEK Conference
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• 2002.07c
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• pp.1740-1743
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• 2002

This paper presents the basic concept of a Solid Freeform Fabrication System using a rapid prototyping procedure. The system can fabricate a ceramic model by laser cutting, accumulating, laminating and sintering of each slice. The system is mainly equipped with a laser apparatus, an x-y table, a material transfer system, and an electric oven. The system could fabricate a small object with smooth surface within comparatively short period of time. The system has also shown its effectiveness in terms of the direct application of the object without the secondary mechanical process. The fabricated sample could directly be applied and used to fairly wide practical areas.