• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.29 no.1
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• pp.35-41
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• 2023

The purpose of this study was to examine the effect of each storage temperature condition of 5, 10, 15 and 20℃ to maintain the freshness of mini paprika (Capsicum annuum cv. New Raon Red) in corrugated box. Changes in general appearance, fresh weight loss, firmness, SSC (solid sugar content), and Hue angle were investigated. Furthermore, storage at temperatures ranging from 5℃ to 15℃ for 14 days resulted in maintaining freshness for 35 days. Paprika stored at 20℃ showed significantly higher loss of fresh weight and firmness than that of other storage temperatures. Furthermore, paprika stored at 5℃ and 10℃ showed a lesser decrease in hue angle than that at 15℃ and 20℃. However, the SSC of mini paprika was not significantly affected by storage temperature. These results suggest that corrugated box packaging in combination with low storage temperatures (5~10℃) could be effective in prolonging the shelf life of mini paprika. Therefore, the results represented that the low temperature storage in combination with cardboard box treatment could be effective in prolonging the shelf life of fresh paprika.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.40 no.4
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• pp.42-50
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• 2003

This paper presents an embedded RC oscillator which has temperature compensation circuits. The conventional RC oscillator has frequency deviation about 15%, which is caused by variation of resistors and the reference voltage of schmitt trigger from the temperature condition. In this paper, the proposed circuit use a CMOS bandgap reference having balanced current temperature coefficients as a triggering voltage of schmitt trigger. The constant current sources consist of current mirror circuit with the positive and negative temperature coefficient. The proposed circuit shows less 3% frequency deviation for variation of temperature, supply voltage and process parameters.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.12 no.3
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• pp.306-311
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• 2019

This paper presents the temperature dependence of transmission-type and reflection-type PPG measurement devices that have been developed in the previous research. PPG signal can be distorted by external temperature such as skin temperature so that many of research was focused on the skin temperature effect. However, this paper focuses on the temperature of the device itself and we studied on the effect of device internal temperature. Experimental results showed that the temperature was increased like an irrational function graph and the transmission-type was not affected by the internal temperature but the reflection-type was affected by the internal temperature.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.2
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• pp.349-357
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• 2007

The most sensitive part of the installed optical fiber fable is the optical loss variation of the splicing part according to the environmental changes. This paper presents the details of the experimental results of the external environmental changes on optical loss, such as bending, temperature variation, temperature variation after water osmosis and vibration. Through the bending test of optical fiber, rapid increase of optical loss was measured within the radius of 30mm. The result of optical loss variation within the temperature range of $-30^{\circ}C{\sim}60^{\circ}C$ is less than 0.02dB. It was confirmed that the maximum optical loss increased up to 0.2dB in case of water osmosis within the temperature range of $-40^{\circ}C{\sim}80^{\circ}C$. There is small optical loss variation of 0.01dB under the 1mm vibration test. The experimental results of this paper can be used as the reference data for the design of the optical fiber cable splicing enclosure to protect the optical loss variation due to environmental changes.

• Elastomers and Composites
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• v.43 no.4
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• pp.213-220
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• 2008

In this study, the effects of curing system on the hardness of rubber materials at various temperature were investigated. NR and SBR were compounded with various sulfur or peroxide content, in order to obtain various crosslink densities. The changes of hardness and crosslink density were measured as a function of temperature and the relationship was examined. The thermal stresses were also measured in order to investigate the effect of entropy as a function of temperature. The hardness of NR and SBR compounds increased with increasing temperature above room temperature, and the measured thermal stress increased as temperature increased. However, the crosslink densities were not changed by temperature change.

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.1117-1120
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• 2009

최근 이상기후와 같은 기후변화로 인한 기온, 강수 등의 변화는 안정적인 수자원 확보에 큰 영향을 미칠 것으로 판단되고 수자원을 필요로 하는 사회 모든 분야에 있어 큰 영향을 끼친다. 특히 농업, 공업, 도시의 용수 공급에 있어 변화는 더욱 심해질 것으로 판단되며 기후변화로 인한 기온, 강수 등의 변화의 정확한 분석이 필요로 한다. 따라서 본 연구에서는 동아시아 해수면 온도와 우리나라 강수량에 대한 MSSA (Multi-channel Singular Spectrum Analysis)를 실시함으로 두 시계열 사이에 공통적으로 나타나는 변화, 즉 특정 상관 주기 변동을 분석함으로 두 변수 사이에 변화 상관 분석을 실시하였다. 우리나라 강수량 자료로는 현재 기상청에서 운영 중인 지상 기상관측소 76개소 중 가용관측소 61개소 자료에 대하여 1973년 1월부터 2008년 12월까지의 자료를 수집하여 월 평균값을 사용하였고 동아시아 해수면 온도 자료로는 한반도 근해 해수면 온도 변화, 남중국해 해수면 온도 변화, 인도양 해수면 온도 변화, 적도 해수면 온도 변화 등을 선택하여 관측시점부터 2008년 12월까지 자료를 수집하여 사용하였다. 분석 자료에 대해 선형 회귀분석을 통한 선형추세 제거와 정규화한 자료를 사용하여 각각의 지수에 대해 MSSA 분석을 실시하였다. 이때 window length는 Vautard 등(1992)이 제시한 N/5$^{\sim}$N/3의 값인 108의 값을 사용하였고 이때 각각의 고유치는 전체 공분산에 대한 각 요소의 비율을 설명한다. 상관분석 결과는 각 지수와 강수자료 사이에 높은 상관성을 가지는 장단주기 변화가 존재함을 보여주었다. 그럼에도 불구하고 우리나라 월강수자료의 전체 변화는 계절변화를 제외하고도 장단 주기를 가지는 시간변화가 자료 전체 변화의 절반에 해당하며 장주기 변화가 나타내는 부분이 미미하다. 이는 계절 주기를 제외한 자료들 사이의 상관변화가 설명할 수 있는 부분이 미미 하며 여러 기상지수들과 국내 강수량사이의 MSSA 분석을 통하여 제시 할 수 있는 변화의 정량적 정도가 매우 제한됨을 보여준다. 그럼에도 불구하고 이러한 접근을 통하여 강수 변화의 불확실성을 줄여나가는 노력이 필요하다고 하겠다.

• Textile Coloration and Finishing
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• v.10 no.4
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• pp.15-23
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• 1998

본 연구에서는 sizing을 포함하여 염색.가공 공정에서 습.건열 처리 온도를 변화시켜 처리한 폴리에스테르 필라멘트 사와 직물의 물성 변화에 관한 상관성을 연구하였다. 경사는 50d/24f(spark) 그리고 위사는 75d/72f(semi-dull)사를 사용하여 평직물을 셔틀직기에서 제직하였다. 사이징 공정에서의 건조온도를 $90^\circ{C}$, $125^\circ{C}$, $150^\circ{C}$로 변화 시켰으며 수세공정에서 습열 처리온도는 $90^\circ{C}$, $110^\circ{C}$ 그리고 $120^\circ{C}$로 변화시켰다. 그리고 프리세트 공정에서의 건열 처리온도는 $180^\circ{C}$, $200^\circ{C}$ 그리고 $220^\circ{C}$로 변화시켰다. 마지막으로 최종열처리 공정에서는 $170^\circ{C}$, $180^\circ{C}$ 그리고 $200^\circ{C}$로 각각 변화시켜 이들 직물의 인장, 굽힘, 전단 특성과 이들 직물에서 채취한 실의 탄성계수, 절단강도, 변형률 등을 측정하여 각 공정에서의 열처리 온도 변화에 따라 이들 물성치의 상관성을 검토 비교하였다.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2007.05a
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• pp.334-337
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• 2007

본 연구는 출력특성의 안정성과 정밀성이 우수한 광전류센서의 개발을 위하여 센싱부의 온도변화에 따른 출력신호를 검토하고, 온도변화에 따른 출력특성이 안정된 센싱부를 적용하여 출력특성을 연구하였다. 기존 광전류센서에서 중요시스템인 센싱부의 광섬유의 온도특성과 Verdet 상수의 온도의존도에 따라 출력신호가 불안정하다. 이러한 광전류센서의 온도변화에 따른 오차를 개선하기 위해 센싱부에 대한 온도특성을 분석하고, 온도변화에 내구성이 뛰어난 소재를 적용함으로써 센싱부의 안정된 출력특성을 가지는 광전류센서를 개발하고자한다.

• Journal of the Korean Geosynthetics Society
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• v.14 no.2
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• pp.57-70
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• 2015

This paper presents the results of an investigation into the effect of forced temperature change cycles on physical and mechanical properties of sand and weathered granite soil. The effect of forced temperature change cylecs on the particle arrangement and the thermal conductivity was first investigated. A series of triaxial compression tests on the soils were also performed to look into the effect of temperature change cycles on the stress-strain-strength behavior. The results indicated that the forced temperature change cycle does not significantly affect the particle arrangement and thermal conductivity. It is shown however that the heating duration showed some effect on the deviatoric stress at failure while no significant effect due to the number of heating-cooling cycle was observed.

• Journal of Energy Engineering
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• v.15 no.3 s.47
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• pp.154-159
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• 2006

An experimental study has been performed to investigate the correlation on compressor discharge temperature of capacity modulated system A/C in cooling mode. Indoor and outdoor temperatures, the cooling capacity, compressor discharge temperature and loading time are measured by the psychrometric calorimeter. The system is controlled by applying the scroll compressor operated by PWM valve and loading duty. With decreasing outdoor temperature, the cooling capacity increases. But, with decreasing indoor temperature, it decreases. According to the increase in outdoor temperature and loading duty, compressor discharge temperature increases. From these experimental data, the correlation on compressor discharge temperature is proposed. The correlation obtained from the present study is agreed with the experimental data within $3^{\circ}C$.