• Journal of Biosystems Engineering
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• v.16 no.3
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• pp.298-311
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• 1991

빈 시스템에서 적정 팬을 선정하기 위해서, 빈에서 벼를 건조 혹은 통풍시킬 때 벼의 저항에 의해 발생되는 공기의 압력손실을 예측하는 모델을 개발하였다. 또한 벼의 건물 손실을 예측하기 위하여 벼의 호흡 모델을 개발하였다. 그리고 온도 및 습도 센서들을 이용한 자동계측 시스템을 사용하여 저장된 벼의 상태를 연속적으로 측정, 분석함으로써 벼의 통풍기준을 결정하고 이를 근거로 빈의 자동통풍 시스템을 개발하여 평가하였다. 공기의 정압 손실은 공기의 속도 및 벼의 함수율의 함수로서 나타내어졌으며, 일정 곡물 깊이에서 벼의 함수율이 낮을수록 그 정압손실은 증가하였다. 벼의 호흡에 의해 발생되는 이산화탄소의 양은 저장온도, 벼의 함수율, 저장 기간의 함수로서 나타낼 수 있었다. 벼의 안전 저장을 위해 곡물의 온도 및 함수율, 평형상대습도, 벼의 품질저하지수(deterioration index)에 대한 자동통풍 기준을 결정하였으며 이들을 이용해서 퍼스널 컴퓨터로 팬, 제습기 등의 통풍 장치들을 자동제어하는 자동통풍 시스템을 개발하였다. 이 시스템은 곡물의 상태를 예측, 제어함으로써 14% 이하의 함수율과 4이하의 품질저하지수, 그리고 어떤 균류도 생성시키지 않음으로써 벼를 안전하게 저장할 수 있었다.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.43 no.6 s.312
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• pp.33-39
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• 2006

Trichromatic LED backlight renders higher colour gamut and panel transmittance to the LCDs than the phosphor-converted white LED backlight. In realization, however, several technical challenges arise, such as colour shift, due to the ambient temperature change, brightness decrease along with the temperature increase, colour mixing, minimizing the total number of chips and so on. In this paper we designed and tested the low cost temperature compensating circuit, using a thermistor as a temperature compensating element, for stabilizing the brightness and maintaining the colour coordinates of the trichromatic backlight units. By applying the temperature compensating circuit, the decrement rate of the brightness and colour shift rate were achieved by 54% and 51% respectively comparing with uncompensated case.

• Journal of Bio-Environment Control
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• v.9 no.2
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• pp.101-106
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• 2000

The practicality of utilizing ventilation pipe to enhance soybean sprout productivity by lowering commodity temperature and resultant sprout rot was tested. The ventilation pipes with holes for aeration were vertically installed inside of a sprout cultivation container prior to adding soaked soybean seeds. The time-series changes in sprout commodity temperature and resultant growth, yield, marketable sprout percentage, and rot of soybean sprouts were measured. The ventilation pipes effectively decreased sprout commodity decreased sprout commodity temperature by 4.7$^{\circ}C$. Ventilation pipes also enhanced sprout yield and marketable sprout percentage by 3.9% and 4.0%, respectively, while reducing sprout rot by 4.1%. In conclusion, ventilation pipe seems a practical and effective non-chemical method to enhance the productivity of soybean sprouts.

• Proceedings of the SAREK Conference
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• 2006.06a
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• pp.1255-1260
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• 2006

This present study analyzed temperature depreciation ratio of window inside surface by KS F 2295 'Procedure for determining fenestration product condensation resistance values'. it estimated window indoor surface condensation due to variable environmental condition. Performance of condensation resistance by using temperature depreciation ratio until applied Low-e and Ar glazing improved about 45% from 24 mm clear. Temperature depreciation ratio by KS F 2295 considers analytic index of window condensation due to variable boundary condition.

• Journal of the Korean Recycled Construction Resources Institute
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• v.8 no.1
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• pp.18-24
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• 2013

Recently, the interest is increasing about the eco-friendly concrete. Accordingly, the blast furnace slag(BFS), a by-product of industry is known for improving the durability through compaction in concrete and is expanding the use. The research about BFS in concrete be accomplished frequently. In this study, we should know the hydration characteristic of BFS concrete the through the adiabatic temperature rise test due to the replacement of a variety of BFS. In addition, we produced the regression analysis factors through the test result and analyzied the effect for the replacement of BFS. According to test results, the compressive strength showed a slight degradation or equal and the the adiabatic temperature rise figure and rising factors are went down for rising replacment of BFS. In the future, the study about the adiabatic temperature rise equation for the various replacement of BFS and binder is considered necessary.

• KOREAN POULTRY JOURNAL
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• v.40 no.12
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• pp.138-141
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• 2008

매년 호흡기 질병의 발생상황은 기후와 밀접하게 연관되어 있다. 이것은 계사 외부온도가 떨어지면서 계사 내의 절대 환기량이 적어짐으로 인해 생기는 공기의 질저하가 질병이 발생하는데 있어 매우 깊은 관계가 있음을 의미한다. 계군에 대한 모니터링을 연중 실시하다 보면 계군에 발생하는 ND나 LPAI와 같은 호흡기 질병의 발생경향을 읽을 수 있다. 2008년 여름은 어느 해보다 길었고 가을 날씨는 최근 몇 년간의 상황과는 매우 다르게 높은 온도를 오랫동안 기록하였다. 온도가 비교적 높은 최근 몇 개월간의 기후 덕에 질병 발생의 정도가 경미하게 나타났다. 계사의 온도가 높게 유지되면서 환기량이 많아 뚜렷한 임상증상(호흡기 증상, 산란율저하)이 없이 내과하는 형태로 질병이 진행되고 전국적으로 ND나 LPAI 등의 발생이 없는 것처럼 보일 수밖에 없었던 것이다. 호흡기 질병의 발생은 외 기온도와 계사 내의 환기량과 밀접하게 연관되어 있다. 결론적으로 매년 발생하는 호흡기성 질병의 대부분은 환기량 부족에 따른 공기질의 저하가 가장 큰 원인 중의 하나라고 해도 과언이 아니다. 올 가을까지의 기후가 질병이 잘 발생하지 않는 상황을 낳았다 하더라도 이제 12월에 접어들면서부터는 계사온도가 당연히 낮아질 수밖에 없고 그로 인한 환기량의 저하에서 오는 호흡기 질병의 발생은 필연적이라 할 수 있다. 따라서 농장에서 체계적인 환기관리를 실시하면 계군에서 발생하는 호흡기 질병을 억제하거나 피해를 현저하게 줄일 수 있다. 이달의 질병관리 포인트로 세심한 환기관리를 제시하고 몇 가지 경험적 사항을 기술하고자 한다.

• Journal of the Korean Recycled Construction Resources Institute
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• v.5 no.1
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• pp.131-138
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• 2010

This research intends to analyze the basic characteristics of cements(hereinafter "CC") with affordable price and particle distribution effective as hydration heat face which are discharged at the outlet of smashing process of ordinary portland cement(hereinafter "OPC") manufacturing process such as fluidity, rigidity, temporary insulation temperature increase amount etc to review the potential of developing "CC" to 3 ingredients low heat cement that substitutes fly ash and blast furnace slag(hereinafter "BS"). As a result of experiment, fluidity tended to decrease with increase in CC substitution rate, and increase with increase in FA+BS substitution rate. Air amount tended to slightly decrease with increase in CC substitution rate, and decrease with increase in FA+BS substitution rate. Condensation characteristics were such that condensation time was delayed with increase in CC and FA+BS substitution rate. As for the temperature rising amount by temporary insulation, peak temperature decreased with increase in CC substitution rate and increase in FA+BS substitution rate in general, and thereafter, temperature tended to decrease slowly. Compressive strength decreased with increase in CC and FA+BS substitution rate, and as aging goes on, long term strength was equivalent to plain or higher. By and large, when FA+BS was substituted to CC, fluidity and air amount tended to decrease, but hydration heat face showed good reduction effects, suggesting possibility of development to 3 ingredients low heat cement.

• The Korea Swine Journal
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• v.10 no.6 s.106
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• pp.83-88
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• 1988

수퇘지의 번식능력은 성성숙, 유전자형, 연령, 영양, 온도, 건강상태, 종부빈도 등의 요인에 의해 성욕감퇴, 수정율 저하, 산자수 감소, 불임, 자돈의 성장저해 등의 심각한 경제적 손실이 발생한다.

• Proceedings of the KAIS Fall Conference
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• 2003.06a
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• pp.181-184
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• 2003

ZnwO₄는 높은 품질계수에 의해 주파수 선택성이 뛰어나지만 다층형태의 고주파 무선부품으로의 응용을 위해서는 높은 소결온도(1100℃), 큰 음의 공진주파수 온도계수(-70ppm/℃), 낮은 유전율(15.5) 둥에 대한 보정이 필요하다. 본 연구에서는 ZnwO₄에 TiO₂ 및 LiF를 첨가하여 ZnwO₄의 저손실특성을 유지하면서 주파수 온도안정성 및 저온소결성을 부여하고자 하였다. 큰 양의 공진주파수 온도계수(＋400ppm/℃) 및 유전율(100)을 갖는 TiO₂의 첨가는 공진주파수 온도계수를 음의 값에서 양의 값으로 변화시켰으며 유전율의 증가를 가져왔다. TiO₂를 20 mol％ 첨가한 경우 공진주파수 온도 계수가 0에 가깜고 유전율 19.4에 품질계수 50000㎓의 특성을 얻을 수 있었으나 소결온도는 1100℃로 높은 소결온도를 보였다. ZnwO₄에 TiO₂가 첨가된 혼합체에 LiF의 첨가는 액상형성에 의해 소결온도를 1100℃에서 850℃로 크게 저하시킬 수 있었다. LiF는 첨가는 LiF 자체의 큰 공진주파수 온도계수에 의해 온도계수를 음의 값으로 변화시켰다. 따라서 TiO₂ 및 LiF의 적당량의 첨가는 온도 안정성을 갖는 저손실 ZnwO₄-TiO₂-LiF계 LTCC 소재를 제조할 수 있었다.

• Journal of the Korea Institute of Building Construction
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• v.12 no.4
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• pp.442-450
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• 2012

In this study, fire resistance and residual strength were examined after the addition of PF fiber and bonding fireproofing gypsum board to a high strength concrete-model column of 50 MPa grade. At the beginning of the experiment, all the properties of base concrete appeared to satisfy the target range. In terms of the internal temperature record, a trend of slightly high temperature was shown when the fireproofing gypsum board was not bonding, and when the fireproofing gypsum board was bonding, as PF content increased gradually, the temperature was gradually lowered. In terms of the relationship, as time elapsed a low temperature was shown when fiber was mixed, and when the board was bonding, the trend of lower temperature could be confirmed. Meanwhile, in terms of spalling property, a severe explosive fracture was generated at PF 0%, and falling off was prevented as the fiber content was increased; however, discoloration and a multitude of cracks were discovered, and when the board was bonding, the trend in which the exterior became satisfactory when the content was increased emerged. In terms of the residual compressive strength, measuring of strength could not be performed at PF 0% without bonding of board, and the strength was increased as the fiber content was increased; however, there was a decrease in strength of about 30 ~ 40%, and in the case of PF 0% with the bonding of board, the strength could be measured; however, about an 80% decrease in strength was shown, and only about a 10 ~ 20% decline in strength was displayed, as the range of decrease was reduced as the fiber content was increased. Considering all of these factors, it was determined that a more efficient enhancement of fire resistance was obtained when two methods are applied in combination rather than when the PF fiber content and bonding of fireproofing gypsum board are utilized individually.