• Journal of Advanced Marine Engineering and Technology
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• 제25권3호
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• pp.588-594
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• 2001

The aim of this paper is to develop the low temperature vacuum dryer, with low initial investments and operating costs, easy operating method and trouble-free operation Usally operations just below atmospheric pressure, as with direct dryers, but some are built for vacuum operation with pressure as low 50 mmHg abs. The lowers the boiling point to $39^{\circ}C$ The experimental data of quantitative analysis for using practically were obtained by the constant drying rate period and reducing drying rate period according to the temperature of hot water which is the experimental parameters of present experiment. As the results, it took about 20 hours for material to reach about 18% of the final moisture content is order to store products for a long time about 450% of the early moisture content at the beginning of drying and maximum drying rate comes to about 0.30 kg/m2hr at about 350% of the moisture content.

• 해양환경안전학회지
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• 제25권3호
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• pp.328-333
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• 2019

During the winter of 2017/2018, significantly low water temperatures were detected around the western and southern coasts of Korea (WSCK). In this period, sea surface temperature (SST) in the Korea Waters was about $2^{\circ}C$ lower than mean temperature. Using the real-time observation system, we analyzed the temporal variation of SST during this period around the western and southern coasts. Low water temperature usually manifested over a period of about 10 ~ 20 days. The daily Arctic oscillation index was also similarly detectable with the variation of SST. From the cross-correlation function, we compared two periodic variations, which were SST around the WSCK and the Arctic oscillation index. The cross correlation coefficients between both variations were approximately 0.3 ~ 0.4. The time lag of the two time series was about 6 to 7 days. Therefore, significantly low water temperatures during winter in the Korean coastal areas usually became detectable 6 to 7 days after the negative peak of Arctic oscillation.

• 한국작물학회지
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• 제42권2호
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• pp.196-201
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• 1997

참당귀 묘크기와 저온처리가 추대에 미치는 영향을 알아보고자 수행한 시험결과를 요약하며 다음과 같다. 1. 저온처리 기간에 따른 추대율은 30일, 60일과 90일 처리에서는 각각 69.4％, 69.3％과 75.2％로 처리기간이 길어짐에 따라 추대율이 높았으며, 무처리에서는 29.6％로 낮았다. 2. 묘크기별 저온처리에 따른 추대율은 소묘일수록 낮고, 대묘일수록 높아지는 경향이었다. 정식후 추대까지의 기간은 저온처리 기간이 길수록, 대묘일수록 추대가 빨라지는 경향이었다. 3. 추대시 생육은 저온처리 기간이 길어지고 대묘일수록 초장이 짧고 추대엽위가 낮으며 진전엽수가 적어지는 경향이었다. 추대율은 추대시 생육과는 부의 상관을 보이고, 후기생육과는 정의 상관을 보였다.

• 농업과학연구
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• 제35권1호
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• pp.1-9
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• 2008

메주를 만들 때 저온숙성의 경우 상온숙성보다 발효 특성과 관련이 있는 pH, 아미노산성 질소 등의 양이 낮았으며 동일한 아미노태 질소 함량에 도달하기까지 숙성기간이 약 2~3배정도 필요한 것으로 나타났고, 된장의 색상이 약 2배정도 밝은 것으로 나타났다. 그리고 숙성초기 낮은 온도로 인해 산성생균의 활동성이 낮아지고 이로 인한 유기산 생성량이 낮아져 상온숙성 된장에 비해 pH가 높고, acidity I이 낮으며, 저온숙성된장은 가수분해 효소에 의한 분해속도의 저하로 낮은 아미노산성 질소 함량을 보였다.

• 화훼연구
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• 제17권4호
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• pp.266-270
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• 2009

깽깽이풀의 임의 개회조절을 목적으로 입실시기, 저온처리 등이 맹아, 생장 및 개화 등에 미치는 영향을 살펴보았다. 입실시기에 따라서는 8월 20일부터 12월 20일까지 입실한 묘는 모두 맹아가 되지 않았다. 그러나 1월 20일과 2월 20일에 입실한 묘는 모두 맹아되어 개화되었다. 저온처리 개시시기와 처리기간이 깽깽이풀의 생장과 개화에 미치는 영향을 살펴본 결과는 8월 고온기에는 60일간의 저온을 받게 되면 맹아하여 개화하였다. 그러나 9월 20일 이후에는 30일간의 저온처리만으로도 거의 전개체가 맹아하여 개화하였다. 이미 저온처리를 한번 받아 휴면이 타파된 주를 재차 저온처리를 하여 2차 개화를 유도한 결과, 실험에 사용된 전 개체 모두 재맹아하였고 이중 70%인 7개체가 개화가 되었다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.199-199
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• 2017

This study investigated the aspects of damage due to low temperature treatment in order to establish the damage criterion according to low temperature invasion during regeneration period in wheat after regeneration period in the early spring. We cultivated wheat cultivar 'Geumgang' in Wagner pots and treated them with three types of low temperature, and the gradual temperature change program was set in a low temperature incubator for 12.5 h per day for 5 days during the night time when the length of young spikes was about 1 mm. All treatments except for the control were treated in 5 steps for each temperature. Treatment 1 was treated at the lowest temperature $-5^{\circ}C$ for 5 h, treatment 2 for 7 h at $-5^{\circ}C$, and treatment 3 for 9 h at $-5^{\circ}C$. The most common type of damage was partial infertility, and there were some discolored spikes. The damage rate of wheat spikes treated at $-5^{\circ}C$ for 9 h was the highest, while the damage rates of wheat sprouts treated at 5h and 7h were not different from each other. It was found that the damage of wheat spikes exposed to low temperatures for a long time was large. It is necessary to investigate the aspects of spike damage by duration days of low temperature.

• International Journal of Industrial Entomology and Biomaterials
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• 제47권1호
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• pp.44-50
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• 2023

The Daehwangjam has excellent marketability and quality. However, precise silkworm breeding data on the recent high-temperature environment is not enough collected, and it is necessary to check whether stable Daewhangjam silkworm egg production was possible in poor environments. In this study, the timing of metamorphosis of the Daewhangjam parents Jam323 and Jam324 silkworms, in an optimal condition and a general condition similar to breeding grounds, was investigated to confirm that appropriate mating was achieved. Surprisingly, a number of female moths were discarded due to the metamorphosis of Jam324 female moths much earlier than Jam323 male moths in either an optimal or a general condition. To improve this, during the Jam324 female pupation period, the mild low-temperature of 15℃ was treated for the pupation period to delay the metamorphosis into female moths. Depending on the treatment period, the metamorphosis of the female pupa was delayed by more than 4 days, allowing normal mating with the Jam323 male moth. The eye pigments in a pupa also slowly accumulated in these treatments. In order to discover the side effects of low-temperature treatments, the voltinism of the Daewhangjam eggs was investigated, but most of them remained univoltine. Taken together, the low-temperature treatment during the female pupation period made it possible to use Jam324 female moths that were should be discarded, which means that stable and efficient management of Daewhangjam egg production is possible.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 C
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• pp.2156-2159
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• 2005

ADS(Address Display Period Separation) driving method has been considered to be the most appropriate driving technique for AC PDP. ADS driving method is composed of reset, address, sustain and erase period. Therefore, a long time should be allocated to an address period, which results in a reduction of brightness. To realize a high luminance and high picture quality, it is necessary to high speed addressing. However, address discharge time lag increases as the temperature decreases, which can cause the misfiring and low picture quality In this paper, the electric field effect and priming particle effect are investigated in order to reduce the address discharge time lag at low temperature. Address discharge time lag was reduced effectively when the priming particles are provided.

• 대기
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• 제22권2호
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• pp.187-197
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• 2012

This study investigates the relationship between the Korean temperature and the atmospheric circulation such as Arctic Oscillation, Siberian High and Aleutian Low during the winter (December-January) for the period of 1970-2011. It is found that all indices to represent aforementioned circulations are significantly correlated with Korean winter temperature for the period of 1970 - 2011. There are marked contrasts in such relationship, however, before and after the mid-1980s when a significant regime shift of Korean winter temperature occurred. While Korean winter temperature has a close relationship with Arctic Oscillation after the mid-1980s, its relationship with Siberian High and Aleutian Low is weakened. The composite analysis between a positive and negative phase of Arctic Oscillation before and after the mid-1980s is conducted to examine a recent strengthening of Arctic Oscillation-Korean winter temperature relationship. It is found that the structural changes of low-level wind and the geopotential height at 500 hPa between the two phases of Arctic Oscillation are more effective to influence Korean winter temperature after the mid-1980s. This may induce a close relationship between the Korean winter temperature variability and Arctic Oscillation after the mid-1980s compared to before the mid-1980s.

• 한국건축시공학회지
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• 제8권2호
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• pp.107-112
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• 2008

According to Korean Architectural Standard Specification (KASS) , at the design stage of the specified concrete strength, strength correction with each temperature level should be considered to secure required strength at 28 days even in low temperature condition, In this paper, the period for the strength correction at the stage of mixture design of the concrete using ordinary Portland cement(OPC) specified in KASS was determined with each region of south Korea based on the meteorological data of KMA(Korea meteorological administration) by applying KASS-5 regulation. In case of 28 days of strength control age, the period for strength correction with 6MPa was calculated to $50{\sim}60$ days and, with 3 MPa. to around 80 days. The period for the strength correction was shown to be decreased with the rise of altitude. The period to consider the delay of the strength development due to low temperature including the period of cold weather concrete was nearly 7 months around 1 year. References for determining the strength correction factors with each region of south Korea was provided in this paper. Further investigation of strength correction of the concrete containing blended cement is to studied.