• Proceedings of the KIEE Conference
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• 2003.10a
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• pp.42-44
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• 2003

The paper presents the method and apparatus for conformal photoresist spray coating on the 3D structured substrate. The system consists of a high-temperature-rotational chuck, ultrasonic spray nozzle module, angle control module and nozzle moving module. The coating uniformity is acquired by controlling the moving speed of the ultrasonic spray nozzle across the substrate which is rotated constantly. To coat the photoresist conformally the spray angle of the nozzle and the temperature of the substrate are controlled during spray coating. The rotational chuck can be heated up by hot air or $N_2$. The photoresist (AZ1512) has been coated on the 3D structured wafer by spray coating system and the characteristics have been evaluated.

• Journal of the Korean Home Economics Association
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• v.27 no.1
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• pp.71-83
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• 1989

This is a basic study designed to discover the most comfortable thermal environment for Korean residences. The purpose of the research is to observe and measure the summer thermal environment in Korean urban detached single family houses and apartments by utilising proposed evaluation standards and methods. The technique used involves the measurement of environmental elements, such as indoor temperature, relative humidity and radiant temperature both in detached single family houses and apartments. Also, in order to understand the resident's thermal comfort response. ASHRAE' thermal sensation 9th level, indoor temperature 5th level, and thermal discomfort 4th level in the psycho-physical voting scale (1972) was used. In conclusion, among Korean urban residences, detached single family houses provided a more stable thermal environment than apartments, as shown by physical psychological evaluations. The possible reason for such stability in detached single family houses may be the usage of reinforced concrete structures which maintain consistent temperatures.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.126-127
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• 2014

At construction sites, due to the reason of inconvenience and difficulties of producing and using curing equipment and when it comes to measuring compression strength of the actual structure, strength of structure concrete according to general standards which are suggested in concrete standard specification are assessed. However, this method does not consider various variables of the sites such as kinds concretes and sizes of frame works so that it is not easy to measure proper curing period and strength. Thus, this study reviews description of strength development according to In-situ temperature system and analyzes and compares properties of strength development of the existing curing methods such as sealing curing so that it provides basic materials for period of removal of molds.

• Journal of Ocean Engineering and Technology
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• v.9 no.1
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• pp.142-151
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• 1995

A simulation program concerned with multi-surface fatigue cracks which initiated at the semi-circular surface notches has been developed to predict their growth and coalescence behaviors at the elevated temperature. Three kinds of coalescence models such as SPC(surface point connection), ASME and BSI(British Standards Institution) conditions were applied, and the results of the simulation were compared with those of the experiment. This simulation is able to enhance the reliance and integrity of structures especially under the elevated temperature which have lots of difficulties in experiments and applications. This shows that the simulation result has utility for fatigue life prediction. Even though all the specimens were the same shape, the error rate was increased in accordance with the applied stress to the specimen. Among the material constants C and m in the narrow band, the results applied upper values of the band to the simulation has shown quite small error compared with the experiment results.

• Journal of Sensor Science and Technology
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• v.5 no.1
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• pp.9-14
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• 1996

The effect on the microwave properties was investigated for the barium titanate doped with impurity of $WO_{3}$ 0.230 mole% produced by conventional solid state reaction method. Microwave resistance, reactance and impedance of the barium titanate were measured with 2-port s-parameter method by using network analyzer, in the range of room temperature to $160^{\circ}C$ and of frequency 300 kHz to 300 MHz. And possibility of frequency sensor and temperature sensor was estimated with barium titanate doped with $WO_{3}$.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.337-338
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• 2006

The 200 nm thick-NiCr films grew on $SiO_2$/Si substrates at various deposition temperatures by a dc magnetron co-sputtering technique were characterized for the variation of film texture. The resistivity of the films decreases with increasing deposition temperature and temperature coefficient of electrical resistance (TCR) varies from negative value to a positive one with increasing deposition temperature. The NiCr films deposited at $300^{\circ}C$ exhibit 4 ppm/K being near zero TCR, resulting in TCR suitable for $\pi$-type attenuator applications.

• Journal of the Semiconductor & Display Technology
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• v.20 no.1
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• pp.37-41
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• 2021

We report on the formation of anodic aluminum oxide (AAO) film using sulfuric acid containing cerium salt. When the temperature of the sulfuric acid containing cerium salt changes from 5 ℃ to 20 ℃, the current density and the thickness growth rate increase. The surface morphology of the AAO film change according to the temperature of the electrolytes. And that affected the breakdown voltage and the plasma etch rate. The breakdown voltage per unit thickness was the highest at 15 ℃, and the plasma etch rate was the lowest at 10 ℃ at 2.80 ㎛/h.

• Journal of the Korean Institute of Gas
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• v.16 no.5
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• pp.28-34
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• 2012

Material degradation of Cr steels in using for boiler tubes was studied in the relation of microstructural changes like carbide behavior and mechanical properties of hardness and creep-rupture life. The carbide dissolution was occurred in 2Cr steel of T22 during high temperature operation. And the grain refinement within martensite lath of 12Cr steel of X20 was derived by the high temperature-long time exposure. But the specific phenomena of material degradation which might be represented by hardness or creep-rupture time of the used tubes were not shown in all the tubes of T22 and X20 even in the fire-side using.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.12
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• pp.1903-1912
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• 2018

Objective: To evaluate the effect of lactic acid bacteria and storage temperature on the microbial, chemical and mycotoxin composition of corn silage. Methods: Corn was harvested at 32.8% dry matter, and chopped to 1 to 2 cm. The chopped material was subjected to three treatments: i) control (distilled water); ii) $1{\times}10^6$ colony forming units (cfu)/g of Lactobacillus plantarum; iii) $1{\times}10^6cfu/g$ of Pediococcus pentosaceus. Treatments in triplicate were ensiled for 55 d at $20^{\circ}C$, $28^{\circ}C$, and $37^{\circ}C$ in 1-L polythene jars following packing to a density of approximately $800kg/m^3$ of fresh matter, respectively. At silo opening, microbial populations, fermentation characteristics, nutritive value and mycotoxins of corn silage were determined. Results: L. plantarum significantly increased yeast number, water soluble carbohydrates, nitrate and deoxynivalenol content, and significantly decreased the ammonia N value in corn silage compared with the control (p<0.05). P. pentosaceus significantly increased lactic acid bacteria and yeast number and content of deoxynivalenol, nivalenol, T-2 toxin and zearalenone, while decreasing mold population and content of nitrate and 3-acetyl-deoxynivalneol in corn silage when stored at $20^{\circ}C$ compared to the control (p<0.05). Storage temperature had a significant effect on deoxynivalenol, nivalenol, ochratoxin A, and zearalenone level in corn silage (p<0.05). Conclusion: Lactobacillus plantarum and Pediococcus pentosaceus did not decrease the contents of mycotoxins or nitrate in corn silage stored at three temperatures.

• Journal of the Korean Society of Clothing and Textiles
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• v.44 no.6
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• pp.1037-1052
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• 2020

This study evaluates the comfort and suitability of safety clothing. We made three safety clothes 'y', 'lg', 'lgH'. Only 'y' made with fluorescence fabric has passed International Standards (ISO 20471). A wearing test investigated the physiological response and subjective sensations at 30℃ and 50% RH, six men participated. Mean skin temperature and tympanic temperature showed significant difference with experimental course (p<.05). The micro-temperature (Tm) showed significant differences between three garments on the thigh (p<.01). When wearing 'lg', Tm was the highest. Micro-humidity indicated the interaction between clothing and the experimental course on the chest with no significant difference; however, there was a low tendency when wearing 'lgH' after the second half of exercise. The sweat rate indicated a significant difference between 'lg' and 'lgH' at 20 minutes of exercise (p<.05). Three sensations showed significant differences with the time (p<.01), there was also a tendency to feel hotter and more humid when wearing 'lg'. Skin sensation showed significant differences between pre-experiment and post-experiment (p<.05), 'y' was the most preferred. The 'lg' with long-sleeved currently worn in Korea tended to feel hotter, more humid and more uncomfortable than 'y'. It indicates that there is room for improvement in Korean safety clothing.