• Journal of Korea Foundry Society
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• v.41 no.4
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• pp.331-341
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• 2021

The effects of austempering temperature, austenitizing temperature and time, added copper content and prior heat-treatment on the processing window of 3.6wt%C-2.5wt%Si ductile cast iron during austempering. The maximum processing window was obtained at 350℃ of austempering temperature. The processing window was increased with increased austenitizing temperature from 850 to 900℃; however, it decreased at 950℃. The processing window was increased with increased austenitizing time from 0.5 to 2 hours and rather decreased for 4 hours. The optimum condition of austenitizing was obained at 900℃ for 2 hours. The processing window was increased with copper content added in the range of 0.0~0.8wt%. The processing window was increased by prior normalizing heat-treatment and decreased by prior annealing in comparison with that for the as-cast state,

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.06a
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• pp.206-207
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• 2020

Accurate estimation of concrete strength development at early ages is a critical factor to secure structural stability as well as to speed up the construction process. The temperature generated from the heat of hydration is considered as a key parameter in predicting the early age strength. Conventionally, concrete temperature has been measured by temperature sensors installed inside concrete. However, considering the measurement on building structures with multiple floors, this method requires reinstallation and repositioning of hardware such as sensors, data loggers and routers for data transfer. This makes the temperature monitoring work cumbersome and inefficient. Concrete temperature monitoring by using thermal remote sensing can be an effective alternative to supplement those shortcomings. In this study, image processing was carried out through K-means clustering technique, which is a unsupervised learning method, and the classification results were analyzed accordingly. In the future, research will be conducted on how to automatically recognize concrete among various objects by using deep learning techniques.

• Journal of the Institute of Convergence Signal Processing
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• v.14 no.2
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• pp.130-135
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• 2013

Recently, the needs of system performances such as working speed and processing accuracy in machine tools have been increased. Especially, the working speed increment generates harmful heat at both moving part of the machine tools and handicrafts. The heat is a main drawback to progress accuracy of the processing. Hence, a oil cooler to control temperature is inevitable for the machine tools. In general, two representative control schemes, hot-gas bypass and variable speed control of a compressor, have been adopted in the oil cooler system. In this paper, the compressor's speed are controlled to keep reference value of temperature at oil outlet. The precision processing of a machine tool is required for an oil cooler guaranteeing ${\pm}0.1^{\circ}C$ temperature control. But the oil cooler with precision temperature control is expensive. Therefore in this paper, instead of a on/off(relay) control method, a PID and phase angle electric power control method is proposed for the precision control of an oil cooler. The proposed controller is implemented and tested at the temperature of $23^{\circ}C$, $24^{\circ}C$ and $25^{\circ}C$.

• International Journal of Highway Engineering
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• v.10 no.3
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• pp.239-246
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• 2008

In this study, the influence of reaction temperatures, mixing time and flexible modifier for crumb rubber modified asphalt(CRMA) as processing conditions were investigated. The temperature susceptibility and adhesion properties of neat and modified asphalts at low temperature measured using the penetration and tensile adhesion test. It was found that processing temperatures and flexible modifier were important factors for tensile adhesion strength and toughness energy at low temperature. The CRMA in the higher processing temperature and flexible modifier exhibited improved tensile adhesion properties which indicated the flexible structure of neat and modified asphalt binder. In general, the improvements of the physical properties in the CRMAs were due to the improvements of miscibility between CR and asphalt binder. It was found that the adhesion properties of the flexible agent modified CRMA were higher than CRMA were related to the flexible agent tend to penetrate into CR particles and asphalt binder.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2004.05a
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• pp.80-83
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• 2004

High temperature deformation behavior of AZ31 Mg alloy was investigated in this study on the basis of a processing map $(\varepsilon\approx0.6)$. To construct a processing map, compression tests were carried out at wide range of temperatures and strain rates $(T=250\~500^{\circ}C,\;\varepsilon=10^{-4}\~100/s)$. Two regions of high deformation efficiency $(\eta)$ were identified as: (1) a dynamic recrystalization (DRX) domain at $250^{\circ}C$ and 1/s and (2) a superplasticity domain at $450^{\circ}C$ and $10^{-4}/s$. Possible deformation mechanisms operating at high temperature were discussed in relation to the activation energy. A two-stage deformation method was found to be effective in enhancing the superplasticity of AZ31 Mg alloy. From the two-stage deformation method, tensile elongation of $1200\%$ was obtained at the superplastic domain.

• Textile Coloration and Finishing
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• v.16 no.1
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• pp.1-4
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• 2004

This research surveys the twisting and untwisting tensions according to the various processing conditions of belt type texturing such as draw ratio, 1st heater temperature and velocity ratio. The 1st heater temperature was changed from 1606{\circ}C\; to\; 220^{\circ}C$, draw ratio was changed from 1.6 to 1.9 and velocity ratio was changed from 1.4 to 1.8. The twisting and untwisting tensions are measured with the variation of these processing conditions, in addition, the untwisting tension(T2) and tension ratio(T2/Tl) according to the various processing conditions are analysed with the false twist mechanism which is affected to the physical properties of draw textured yams.

• Journal of Biosystems Engineering
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• v.35 no.3
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• pp.169-174
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• 2010

This study was conducted to investigate the effect of abrasive processing and non abrasive processing in the milling process on the quality of rice. The effect was analyzed based on the factor such as whiteness, grain temperature, moisture content, crack and broken rice ratio. The results were as followings. Whiteness of abrasive rice was the same as non abrasive rice. The rice temperature increase of abrasive rice was $1.6^{\circ}C$ lower than non abrasive rice. The crack ratio was increased in the process of milling and non abrasive rice showed higher values than abrasive rice. The broken rice ratio of the using abrasive processing was about 0.05% lower than that of non abrasive processing. The moisture content decreased in the process of milling regardless of the use abrasive rice milling machine.

• Journal of Acupuncture Research
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• v.15 no.2
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• pp.1-15
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• 1998

Purpose : The study for changes in components and acitvities of Artemisiae Herba at various processing temperature is generally regarded as a foundation in setting the optimum heat-processing temperature and for getting the maximum activities for medical usage of this herb. Methods: Therefore some experiments were performed either in vitro or in vivo and various changes were observed - the changes in the weitht of Artemisiae Herba, the changes in the relative amount of three kinds of extracts from Artemisiae Herba ( diluted ethanol extract, water extract, ether extract ), the TLC pattern of essential oil at various processing temperature, the existance of inhibitory effects both on ${\beta}$-Glucuronidase activities, and on heat-induced hemolysis, the effects on increased vascular permeability. The valid results derived from the experiments are as follows. Results: 1. The weight of Artemisiae Herba prominently decreased at 240^{\circ}C$. 2. The contents of diluted ether extract were maximum in the unprocessing condition. Those of water extract were maximum at 180^{\circ}C$ and at 210^{\circ}C$. and the changes of diluted ethanol extract at 150^{\circ}C$. 3. The TLC pattern of essential oil in Artemisiae Herba at various processing temperature showed that a component began to increase at Rf 0.56 and another component began to decrease at Rf 0.86. 4. The contents of Eupatilin in Artemisiae Herba at various processing temperature continued to decreased in proportion to the temperature rise, the extent of which was prominent at 210^{\circ}C$, and was unnoticeable at 270^{\circ}C$. 5. Inhibitory effects on ${\beta}$-Glucuronidase activities, trypsin activities and heat-induced hemolysis increased in proportion to the density of Artemisiae Herba. Inhibitory effects on ${\beta}$-Glucuronidase activities and trypsin activities were relatively high at 180^{\circ}C$ while on the writhing syndrome and inhibitory effects on increased vascular permeability induced by acetic acid were maximum at 240^{\circ}C$. those on heat-induced hemolysis were relatively high at 240^{\circ}C$. 6. In vivo, both analgesic effects Conclusions: To maximize of the effectiveness of Artemmisiae Herba, the ideal heating temperature is in the range of 180^{\circ}C{\sim}240^{\circ}C$.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.27 no.3
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• pp.107-112
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• 2013

Cu(In,Ga)$Se_2$ (CIGS) thin films were annealed on molybdenium/sodalime glass substrates of $300{\times}300mm^2$ by rapid thermal processing (RTP) with 2-step rising-temperature times in $N_2$ ambient. Morphological property, structural characteristics and chemical composition of the precursor of CIGS thin films were influenced directly with a change of $1^{st}$-step rising-temperature time in RTP whereas there is no significant difference with the different $2^{nd}$-step rising-temperature time (final crystallization temperature). The shorter $1^{st}$-step rising-temperature time in RTP obtained the higher photovoltaic cell efficiency from 7.469% to 8.479% even though the ideal composition in CIGS thin films could not be accoplished in this study.

• Food Science of Animal Resources
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• v.39 no.2
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• pp.296-308
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• 2019

Although the yellow mealworm (Tenebrio molitor L.) is a promising alternative protein source, the effects of processing conditions on functional properties are unclear. In this study, a protein extract of yellow mealworm larvae (PEYM) was subjected to different heat temperature ($55^{\circ}C$, $75^{\circ}C$, and $95^{\circ}C$) with different time (20, 40, and 60 min) to evaluate the functional properties and protein oxidation. Different heat temperature treatment significantly affected the exposure of surface hydrophobicity of the proteins and protein molecule aggregation, which reached maximum levels at $95^{\circ}C$ for 60 min. Protein oxidation was inversely proportional to the temperature. Both the highest carbonyl value (1.49 nmol/mg protein) and lowest thiol value (22.94 nmol/mg protein) were observed at $95^{\circ}C$ for 60 min. The heating time-temperature interaction affected several functional properties, including solubility, emulsifying potential, and gel strength (GS). Solubility decreased near the isoelectric point (pH 5 to 6). As the temperature and heating time increased, emulsifying properties decreased and GS increased. The oil absorption capacity and foaming properties decreased and the water absorption capacity increased. These results confirmed that PEYM is a suitable source of proteins for processing and applications in the food industry.