• 한국광학회지
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• 제27권1호
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• pp.32-40
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• 2016

광학계의 특성은 파장과 온도에 따라 변화한다. 이 연구에서는 얇은 렌즈 근사를 이용하여 특정한 기준파장과 기준온도에서 파장과 온도변화에 안정한 광학계를 설계하는 방법에 대하여 연구하고, 이를 기반으로 2매의 렌즈로 구성된 레이저 주사광학계를 설계하였다. 설계된 레이저 주사광학계는 기대한 바와 같이 파장과 온도 변화에 따른 유효초점거리의 변화가 매우 적음을 확인 할 수 있었다.

• 센서학회지
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• 제18권5호
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• pp.343-348
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• 2009

$NiO{\cdot}(Co_{0.25}Mn_{0.75})_2O_3$(Mn-Ni-Co) and $Ba_{0.5}Sr_{0.5}TiO_3$(BST) thick films were screen printed on Pt patterned alumina substrate to investigate the effects of sintering temperature on humidity and temperature sensing properties of ceramic sensors. A raise in sintering temperature increased resistance and B constant of the Mn-Ni-Co temperature sensor. This may have derived from the synergic effects of the reduction in charge carriers caused by the substitution of Co for Mn as well as the formation of microcracks from the difference in thermal expansion coefficients. Dependence of resistance on humidity of the Mn-Ni-Co temperature sensor, however, was not found. BST films sintered at temperatures in the range of $1100^{\circ}C$ to $1150^{\circ}C$ showed excellent humidity sensing properties. The BST humidity sensor was faster in its response than the Mn-Ni-Co temperature sensor. The humidity sensor, however, proved to be unstable under various temperatures, suggesting a need for a temperature stabilizing device. In contrast, the Mn-Ni-Co temperature sensor was stable under humid conditions.

• 소성∙가공
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• 제18권2호
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• pp.107-111
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• 2009

Temperature variation happens in micro prism roll mold processing system during machining the prism pattern roll mold using manufacturing optical films of LCD (liquid crystal display). This temperature variation induces pitch errors of the prism patterns. The temperature variation displaces the positions of the diamond cutting tool on the roll which was coated by the copper. In order to prevent the pitch errors, the stabilizing the temperature of machining environment is needed. Therefore, the researching on the temperature variation of the ultra-precision roll mold processing system on the machining of micro prism rot 1 mold is needed. In this paper, the temperature variation of micro prism roll mold processing system is researched, the influence is analyzed, and the study for reducing the pitch errors carried out.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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• pp.872-877
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• 1991

This paper presents the composite control method using fuzzy and neural network theory. Fuzzy theory is applied to make control rules and neural net is used to learn them and to generate proper control signals. The electric furnace is controlled to maintain the desired temperature and to minimize the fluctuation of the temperatures in various locations inside the furnace. This controller consists of three neural nets which deal with the average of the temperatures, variances of them and the temperature stabilizing mechanism. Experiments are performed with the target temperatures of 70.deg. C and 80.deg. C. Test results show that this simple method is very effective.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2003년도 춘계학술대회 논문집
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• pp.265-271
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• 2003

This study is for the stable optical source in order to get the precision measurement, which contributes to help the laser frequency and the output to be settled. The laser optical frequency is changed by the length of resonance cavity. The length variation of the laser resonance amplitude is affected by the thermal expansion of that system. So, we try not only to adjust the temperature of the laser tube using the heater for fine length of resonance cavity, but also to maintain the fixed temperature of the resonance cavity for outputting the safe laser optical frequency. Therefore, we must take materials with the thermal expansion of the supporting system, which is closer to it of the laser resonance cavity. Using the materials, we can promote to stabilize the temperature of it. In advance, we also plan to get the settlement of the laser frequency and the output in the long km, optimizing and stabilizing the system.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 가을학술발표대회논문집
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• pp.65-66
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• 2023

This study is aimed to understand the effect of pyrolysis temperature on the biochar synthesis for shape stabilizing the Lauric acid (LA). Three different temperatures (350, 500, and 650 ℃) have been chosen with a soaking time of 1h for synthesizing biochars form sesame plants (SP). The structural characterizations indicate the formation of amorphous biochar at 350 ℃ whereas, a stain of graphene formation has been observed for the biochar synthesized at 500 ℃. Formation of a substantial amount of graphene has been found for the sample, synthesized at 650 ℃. Energy storage performances of the PCMs which are shape stabilized by these three biochars have been discussed in this paper.

• 대한기계학회논문집B
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• 제20권11호
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• pp.3666-3675
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• 1996

A new hardware temperature compensation method for hot-wire anemometer is investigated and an analog compensating circuit is proposed in this article. A photoconductive cell is introduced here as a variable resistor in the anemometer bridge and the linearized output of a thermistor is used to monitor the input of the photoconductive cell. In contrast with the conventional method, any type of temperature sensor can be used for compensation if once the output of thermometer varies linearly with temperature. So the present technique can diversify the compensating means from a conventional passive compensating resistance to currently available thermometers. Because the resistance of a photoconductive cell can be set precisely by adopting a stabilizing circuit whose operation is based on the integration function of the operational amplifier, the accuracy of compensation can be enhanced. As an example of linearized thermometer, thermistor sensor whose output is linearized by a series resistor was used to monitor the fluid temperature variation. Validation experiment is conducted in the temperature ranged from 30 deg. C to 60 deg. C and the velocity up to 40 m/s. It is found that the present technique can be adopted as a compensating circuit for anemometer and hot-wire type airflow meter.

• 동의생리병리학회지
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• 제18권6호
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• pp.1723-1727
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• 2004

We investigated the activity and stability of alcohol dehydrogenase from horse liver (HLADH) under the electric stimulation. The activity and stability of alcohol dehydrogenase depended on electric output voltaqe, stimulation time, pulse duration and pulse interval, and temperature. HLADH retained about 23% of its activity in buffer but 78% in 10% trehalose solution under electric stimulation with 10V, 10min, The stabilizing of enzymes against electric stimulation by stabilizing additives showed a great potential use of enzymes in biotechnology and medical engineering fields.

• 한국식품조리과학회지
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• 제32권3호
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• pp.325-332
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• 2016

Purpose: The purpose of this study was to investigate the stability of anthocyanin pigment extract from Yangha (Zingiber mioga ROSC). Methods: Yangha extract was investigated for the effects of metal ion, temperature, light, heating time, sugars, and organic acids on the stability of anthocyanin pigments. Results: Yangha pigment was more stable than other anthocyanin pigments at unstable temperatures. The stability of anthocyanin pigment significantly decreased one day after exposure to light. All tested sugars decreased the abundance of Yangha pigments, with highest levels in the presence of sucrose, and progressive decrease in the presence of maltose, fructose, glucose and galactose, in order. Among the organic acids tested, citric acid and malic acid were the most effective in stabilizing the Yangha pigment, followed by acetic acid and formic acid. Most metal ions except $Fe^{2+}$ were effective in stabilizing the pigment. Conclusion: These results provide useful reference data for the use of pigments from Yangha in processed foods.

• 전자공학회논문지SC
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• 제43권6호
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• pp.33-39
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• 2006

적, 녹, 청색 3파장 LED를 적용한 LCD 백라이트 조명은 백색 LED를 적용한 것에 비해 넓은 색재현성과 LCD 투과율을 실현할 수 있으나, 온도 변화에 따른 휘도 저하와 색좌표 변동 문제 등의 신뢰성을 확보하지 않으면 안된다. 본 논문에서는 정전류 전원을 사용하는 소형 3파장 LED 백라이트 조명에 온도 보상 소자로서 써미스터를 사용한 저가형 온도 보상 장치에 대해 소개하고, 설계 및 실험 결과를 나타내었다. 이 방법에 의해 휘도 저하율을 54% 개선하였고, 색좌표 변동율을 51% 줄일 수 있었다.