• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.4
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• pp.16-23
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• 2020

An electric vehicle operates at high currents and requires real-time monitoring of the entire system for ensuring efficiency and safety of the vehicle. Current sensors are applied to drive the motors, inverters, and battery control systems, and are the key components to ensure constant monitoring of the magnitude and waveforms of the operating current. In this study, a heat treatment process condition to influence the performance of Permalloy current sensors was developed; the correlation between the output capacity, low-temperature characteristics, and high-temperature characteristics of the current sensor was studied; and the process was optimized to meet the required output accuracy and temperature characteristics.

• Journal of the Korea Organic Resources Recycling Association
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• v.6 no.1
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• pp.67-73
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• 1998

This study was to experiment, through sewage sludge treatment by Vacuum Drying Method, variation of water content with reaction pressure, reaction time, reaction temperature. The result are as follows; The water content decreased with the same reaction temperature and reaction time at lower pressure and 360~40 mmHg (a close vacuum) showed lower water content at low reaction temperature and short reaction time. The water content rapidly decreased with the same reaction pressure and time at low reaction temperature (above $120^{\circ}C$).

• Environmental Engineering Research
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• v.24 no.3
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• pp.501-512
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• 2019

The seasonal effects on the biostability of drinking water were investigated by comparing the seasonal variation of assimilable organic carbon (AOC) in full-scale water treatment process and adsorption of AOC by three filling materials in lab-scale column test. In full-scale, pre-chlorination and ozonation significantly increase $AOC_{P17\;(Pseudomonas\;fluorescens\;P17)}$ and $AOC_{NOX\;(Aquaspirillum\;sp.\;NOX)}$, respectively. AOC formation by oxidation could increase with temperature, but the increased AOC could affect the biostability of the following processes more significantly in winter than in warm seasons due to the low biodegradation in the pipes and the processes at low temperature. $AOC_{P17}$ was mainly removed by coagulation-sedimentation process, especially in cold season. Rapid filtration could effectively remove AOC only during warm seasons by primarily biodegradation, but biological activated carbon filtration could remove AOC in all seasons by biodegradation during warm season and by adsorption and bio-regeneration during cold season. The adsorption by granular activated carbon and anthracite showed inverse relationship with water temperature. The advanced treatment can contribute to enhance the biostability in the distribution system by reducing AOC formation potential and helping to maintain stable residual chlorine after post-chlorination.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.29 no.12
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• pp.28-32
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• 2015

In this work, we reported fabrication of sealing the glass substrate using laser treatment at low temperature for electrochemical luminescence (ECL) cell. The laser treatment at temperature is using laser diode. The glass substrate sealing by laser treatment tested at 3-10W, 2-5 mm/s for build and tested. The sealing laser treatment method will allow associate coordination between the two glass substrate was enclosed. The effect of laser treatment to sealing the glass substrate was found to have cracks and air gap at best thickness of about 550-600 im for condition 3 W, 3 mm/s. The surface of sealing was roughness which was not influent to electrodes It can reduce the cracks, crevices and air gaps as well, improves the performance viscosity in butter bus bar electrodes. Therefore, it is more effective viscosity between two FTO glasses substrate.

• Current Research on Agriculture and Life Sciences
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• v.11
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• pp.43-54
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• 1993

This experiment was conducted at Andong county cropping season to investigate rice response and consequent changes in the physiological activities and agronomic characters of rice as affected by growth regulator treatments, and to determine how low temperature controls some plant growth mechanisms. Plant growth regulators, particularly ABA, applied to 15 DAT regardless of concentration, gave higher tar plant height and tiller number after 10days of low temperature treatment than did the untreated plant. However, the differences in plant height and tiller number among treatments diminished to plant growth. Chlorophyll content seemed to be enhanced by growth regulators under low temperature condition. The 10-day treatment of low temperature decreased chlorophyll content by more than 17% compared with the untreated control. The oxidizing activity of roots decreased sharply to 52.2a after 10 days in low temperature condition. On the other hand, ABA at concentration of $10^{-4}M$, highly attains oxiding activity of roots. Generally, plant growth regulators applied at 15 DAT under low temperature reduced grain yield more than did the untreated control which can be attributed to decreased yield components. When growth regulators were applied to booting stage, the tiller number did not show significant difference, whereas the significant difference in culm length at harvest was observed in all treatment as a result of different concentration of growth regulators. The growth regulators generally exhibited a significant effect on yield component except on panicle length. Grain yield of low temperature treated plot at booting stage was significantly influenced by application of growth regulators. This was due to decreased number of spikelet and low filled spikelet percentage. However, TIBA treatment at booting stage showed no significant differences in grain yield.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.5
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• pp.803-807
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• 2008

A making process of DSC(dye sensitized solar cell) was presented. In general, Photo electrodes of DSC was made by using colloid paste of nano $TiO_2$ and processing of Doctor-blade printing and high temperature sintering for porous structure. These methods lead to cracks on $TiO_2$ surface and ununiform of $TiO_2$ thickness. This phenomenon is one factor that makes low efficiency to cells. After $TiO_2$ printing on TCO glass, a physical vibration was adapted for reducing ununiform of $TiO_2$ thickness. And a thermal treatment at low temperature(under $75^{\circ}C$) was adapted for reducing cracks on $TiO_2$ surface. In this paper, we have designed and manufactured an ultrasonic circuit (100W, frequency and duty variable) and a thermal equipment. Then, we have optimized forcing time, frequency and duty of ultrasonic irradiation and thermal heating for surface treatment of photo-electrode of DSC. In I-V characteristic test of DSC, ultrasonic and thermal treated DSC shows 19% improved its efficiency against monolithic DSC. And it shows stability of light-harvesting from drastically change of light irradiation test.

• Textile Coloration and Finishing
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• v.24 no.4
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• pp.313-320
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• 2012

For the preparation of hardened films which can be applied as a binder for flame-resistant materials such as silica, linseed oil was subjected to a low temperature plasma treatment with argon, or oxygen gas. The film was produced much faster than so-called drying of oil in air. The SEM analysis for silica particles embedded in the hardened film after plasma treatment showed that the silica particles were immobilized on substrate and were evenly dispersed. The FT-IR spectral analysis for the plasma-treated linseed oil films demonstrated that the radicals which were formed during the plasma treatments caused the linseed oil to be cross-linked, and the plasmas attacked carbon chains of the oil randomly without focusing on specific vulnerable bonds such carbon double and carbonyl bonds intensively unless exposure times of the plasmas were prolonged too much, while the cross-linking of the air-dried film was considered to occur at the well-known typical sites, i.e., carbon-carbon double bond and ${\alpha}$-methylene carbon. Burning times, as a measure of flame/fire resistance, of silica-filled cellulose substrates, increased with increasing contents of silica.

• Journal of the Korean institute of surface engineering
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• v.38 no.3
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• pp.118-125
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• 2005

Low temperature plasma treatment with different gases and rf powers were performed to improve the adhesion strength between polytetrafluoroethylene(PTFE) and electroless deposited copper. According to the research, $H_2$ plasma having hydrogen radical was more effective in surface polarity modification than $O_2$ plasma due to the defluorination reaction. However, surface roughness of PTFE was more increased with $O_2$ than $H_2$ plasma. PTFE treated with $120W-O_2$ plasma and $250w-H_2$ plasma, consecutively showed rougher surface than single step $250w-H_2$ plasma treated one and more hydrophilic than single step $120W-O_2$ plasma treated one. And it showed 5B tape test grade, which is better adhesion property than 1B or 3B obtained by single step plasma treatment. In addition, adhesion strength between PTFE and Cu deposit is also deeply affected by residual water on its interface.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.30 no.5
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• pp.200-207
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• 2020

MoSi₂, (Mo_1/2W_1/2)Si₂, and WSi₂ powders were synthesized by self-propagating high-temperature synthesis (SHS) method. The synthesized powders were heat-treated at 500, 1,000, 1,200, 1,300, 1,400, 1,500 and 1,600℃ in ambient atmosphere. Oxidation of Mo-W silicide powder was found at low temperature of 500℃. XRD structure analysis and DTA/TG data showed that MoO₃ was formed with 500℃ heat treatment for 1 hour, and that it was α-cristobalite phase that was formed with 1200℃ heat treatment, not α-quartz phase which is commonly found and stable at room temperature. Existence of W accelerated decomposition at both low and high temperature. Fully sintered MoSi₂ and (Mo_1/2W_1/2)Si₂ specimen did not show decomposition or weight loss by oxidation, with 1 hour heat treatment at either low or high temperature. Notably, it was difficult to sinter WSi₂ because of oxidation reaction at low temperature.

• Horticultural Science & Technology
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• v.32 no.2
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• pp.202-209
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• 2014

This study was conducted to investigate the effects of low temperature shipping condition and precooling treatments (forced air and room cooling) on everbearing strawberry through export simulation of 'Goha' and 'Flamenco' cultivars. After harvest, it took two days to prepare export procedure such as precooling, sorting, storage, transportation, quarantine and handling, and then everbearing strawberry was carried out shipping at room ($20-25^{\circ}C$) or low ($8^{\circ}C$) temperature conditions. In the case of shipping at room temperature, weight losses of both cultivars were increased up to 10% after 2 days where 'Goha' being 2% higher than that of ' Flamenco'. In 'Flamenco' cultivar, shipping temperature and precooling treatment were not effective in firmness and soluble solids contents during transporting periods. However, in 'Goha' cultivar, room cooling treatment and low shipping temperature were effective in maintaining firmness until 4 days after shipping. Especially titratable acidity was affected by shipping temperature ($P{\leq}0.001$) and precooling treatments ($P{\leq}0.05$) in 'Goha' cultivar. Also shipping temperature under $8^{\circ}C$ delayed coloring and decay incidence of both strawberry cultivars, and precooling treatments of both forced air and room cooling reduced frequency of decay. The shelf life of everbearing strawberry at low shipping temperature was extended more than 4 days compared with shipping at room temperature. Precooling treatment including forced air or room cooling will be useful for the two cultivars when they are transported at low temperature. In 'Flamenco' cultivar, the effect of forced air and room cooling was similar, whereas in 'Goha' room cooling was more effective.