• Nuclear industry
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• v.7 no.10 s.56
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• pp.53-66
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• 1987

오늘날 점점 더 많은 사람들이 밤샘을 하게 되었고 밤과 저녁 근무는 점점 더 보편화 돼 가고 있으며 낮근무만 하는 직장을 구하기가 점점 더 어려워지고 있다. 교대근무자들은 수면, 소화기능, 가족, 사회생활 등에 얽힌 문제점들을 어떻게 풀어나갈 것인가.

• Korean Journal of Food Science and Technology
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• v.31 no.5
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• pp.1216-1220
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• 1999

The effects of low-temperature blanching on the physical properties of chestnut powder were studied. Chestnuts were blanched in water for 15, 30 and 60 min., each at three temperatures viz. $45^{\circ}C,\;55^{\circ}C$ and $65^{\circ}C$. The particle size of chestnut powder was prepared smaller than 60 mesh$(250\;{\mu}m)$. Higher blanching time and temperature increased water binding capacity(WBC) of chestnut powder. Water soluble index(WSI) was the highest for chestnuts blanched at $65^{\circ}C$ for 30 min. As with water binding capacity(WBC), swelling power of chestnut powder increased with increasing blanching time and temperature but solubility showed an reduction by increasing blanching temperature. In Brabender amylographic examination, peak viscosity of chestnut powder showed great change, but the gelatinization temperature showed no significant differences by blanching conditions.

• Korean Journal of Ichthyology
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• v.18 no.3
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• pp.178-183
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• 2006

Diel changes in the feeding habits of Rudarius ercodes were investigated in an eelgrass bed of Jindong Bay, Korea. The main food components for R. ercodes (1.6~ 4.3 cm SL) were gammarid amphipods, eelgrass, polychaetes and urochordates. Most dietary items were inhabitants of an eelgrass bed. Diel variations in diet and feeding activity occurred. The diet of R. ercodes underwent changes from eelgrass and gammarid amphipods (omnivore) at day to mainly gammarid amphipods, polychaetes, and urochordates (carnivore) at night. Rudarius ercodes probably took detached eelgrass leaves and grazed live eelgrass during day, whereas feeding on gammarid amphipods, polychaetes, urochordates, and bivalves were facilitated by nocturnal movement and activity of these prey during night. The feeding activity of R. ercodes was also correlated with periods of high tides.

• 농업기술회보
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• v.47 no.5
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• pp.40-41
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• 2010

큰 일교차는 가축면역력 약화를 부른다. 낮과 밤의 일교차 약 $10^{\circ}C$ 전후의 환절기에는 면역력이 약한 어린 가축은 환경의 변화에 따른 대사불균형으로 질병 발생률이 높아진다. 가축에게 환경 스트레스를 낮춰주기 위해 아침 저녁으로 바깥의 찬공기에 노출되지 않도록 차단해야 하고 야간에는 축사보온, 낮에는 환기가 충분히 이루어지도록 해야 한다. 또한 양질의 사료공급은 물론 비타민, 광물질 등의 첨가제를 적절히 배합해 급여하고 호흡기 질병 및 설사병 등의 백신을 적기에 접종해 면역능력을 가질 수 있도록 해야 한다.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.3
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• pp.340-348
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• 1997

Sledge net samples were taken over the neap and spring tide cycles in January 1993 from the bottom and surface of 1 m depth and at the water's edge in the sandy shore surf zone of Dolsando, southern Korea. Zonation pattern of three dominant gammarid amphipods was compared. The amphipods were more abundant on the bottom and at water's edge than in the surface. Average densities at both sites of Pontogeneia rostrata and Allorchestes angusta were higher during the neap tide than the spring tide, whereas that of Synchelidium lenorostralum was lower during the neap tide. P. rostrata migrated horizontally during the flooding and ebbing tides, but S. lenorostralum and A. angusta did not. Unlike other species, P. rostrata was significantly more abundant at night, suggesting its active nocturnal movement. During flooding tide, P. rostrata was not found on the shore above the mean sea level (MSL) during daytime, but found in 100 cm above MSL at night. Zonal distribution of P. rostrata which was restricted from MSL to 250 cm below MSL, however, did not vary with the day-night cycle during ebbing tide. S. lenorostralum and A. angusta were not found during flooding tide but ebbing tide. The upper distribution limit of the former was 150 cm below MSL, and the distribution of the latter ranged from MSL to 150 cm below MSL. The highest densities of P. rostrata, S. lenorostralum and A. angusta were 32, 26 and 3 ind. $m^{-2}$, respectively. We discussed the relationships between the distribution pattern of three dominant species of gammarid amphipods and their life styles in the sandy shore.

• Journal of agriculture & life science
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• v.43 no.5
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• pp.47-55
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• 2009

This study analyzes the correlation between noise and the size of urban forests. Under the assumption that the main cause of the noise m the city is the population density, the size of urban forests per capita and the ratio of urban forests with respect to the size of urban per 100 thousand persons are used for the calculation of correlations with noise. The results of the calculations of Pearson's and Spearman's correlation coefficients indicate that the increase in the size of urban forests has a significant effects in reducing the day-time as well as night-time noise for most regions in the cities. The size of urban forests within public parks has a significantly negative correlation with the noise. However, calculated correlation coefficients imply the increase in the size of total urban forests is more effective in reducing the noise than the increase in the urban forests in public parks.

• Proceedings of the KSRS Conference
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• 2008.03a
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• pp.125-130
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• 2008

Mid-Infrared (MIR) 영상은 화산 활동 및 산불로 인한 재난관측, 지표물질 관측, 해수 온도 측정과 같은 분야들에서 사용되고 있다. 그러나 MIR영역은 지표의 복사율과 대기의 영향으로 인한 변화가 매우 심하고, 낮 영상의 경우 태양 복사량에 의한 영향도 고려해야 하는 어려움이 있다. 따라서 단일밴드인 MIR영상을 이용하여 표면온도를 얻기 위해서는 영상이 취득된 시간과 장소에서 관측된 태양 복사량 및 여러 가지 대기 변수가 필요하다. 본 연구의 목적은 기존의 MIR 영상 연구가 다중밴드를 기반으로 한 것과 달리 단일 밴드의 영상을 이용하여 표면온도를 측정하는데 있다. 이를 위하여 MODIS MIR 영상을 대상으로 MODTRAN을 사용하여 MIR 영역의 대기보정 기법을 적용 한 뒤 복사전달 모델을 이용하여 지표의 복사량을 측정하였다. 획득된 지표온도 영상의 정밀도를 측정하기 위해서 기존의 온도 알고리즘인 split-window algorithm에 의해 얻어진 해수온도 영상과의 비교를 통하여 오차 원인에 대해 분석을 실시하였다. 그 결과 낮 영상의 경우 -4.19${\pm}$1.19$^{\circ}C$ 정도의 온도 차가 났으며, 밤 영상의 경우 0.5$^{\pm}C$0.39$^{\circ}C$ 정도로 비교적 좋은 결과를 보였다. 이는 낮 영상의 경우 지표의 복사율에 대한 온도의 민감도가 매우 높기 때문에 높은 오차가 발생하지만, 밤 영상의 경우 태양빛에 의한 영향이 없으므로 좋은 결과를 나타내기 때문이다. 따라서 단일밴드 MIR영상을 이용한 지표온도 추정 시 대기에 의한 영향보다 지표 복사율에 의한 영향이 높다고 추정할 수 있다.

• Journal of Science Education
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• v.44 no.1
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• pp.1-14
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• 2020

In this study, we analyzed the written and drawn explanations of thirty elementary school pre-service teachers in order to examine their perception on the seasonal length of day and night. The main findings are as follows: First, pre-service teachers used the most common term in the description of the texts, such as meridian altitude, axis of rotation, and revolution, and there were more misconceptions in the drawn explanation than in the written explanation. Second, by analyzing the pre-service teachers' perceptions by combining written and drawn explanations, it is possible to detect scientific errors that the distance between the Earth and the Sun is closer when the axis of rotation is tilted in relation to the revolution and seasonal changes due to changes in the orbital radius of the Earth. In addition, there have been types of explanations such as seasonally changing meridian altitudes related to the rotation of the Earth but no change in the location of the Sun. Based on the results of the analysis, we discussed the lack of experience in constructing an explanatory system of specific phenomena using scientific knowledge, lack of observational experiences about natural phenomena, and lack of exposure to other explanatory systems that cause cognitive conflicts. We hope that it will be concrete and practical help to improve the understanding of pre-service teachers in the science domain of primary teacher training program.

• Journal of Science Education
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• v.46 no.2
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• pp.151-164
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• 2022

The 2015 revised science curriculum textbook of 6th graders describes 'day and night' as an astronomical phenomenon observed on a daily basis. Textbooks use only visual materials from a space-based perspective to explain the causes of day and night. This study aims to investigate what changes in spatial representations of 5th graders when additional visual materials of the Earth-based perspective were presented to them. It also shows that the Space and the Earth-based perspectives appear to be interconnected. The following are found in this study. First, when students were presented with a visual material of an Earth-based perspective, their spatial representations of both the Earth and the Space-based perspectives changed. Second, the visual material of an Earth-based perspective confirmed the possibility that students' spatial representation types could be different in many ways. Third, the effect on the spatial representation of each perspective is different depending on gender and the level of spatial representation.

• Journal of Korean Society of Forest Science
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• v.106 no.1
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• pp.26-32
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• 2017

We studied the effects of dip treatments of natural extracts (Camellia sinensis, Angelica gigas, Astragalus membranaceus, Glycyrrhiza uralensis: 1% extract) on the quality of peeled 'Daebo' chestnut. After dipping treatment peeled chestnuts were vacuum packaged with $75{\mu}m$ PE+Nylon 7-layer film then stored in $4^{\circ}C$ incubator for 35days. The quality changes including the surface color and off-odor were evaluated for storage days. The natural extracts dipping treatment on peeled chestnut was effective on skin browning inhibition. Especially, Astragalus membranaceus and Glycyrrhiza uralensis extract treatments was significantly effective in reducing surface browning. The color change (${\Delta}E$) of peeled chestnut was the highest (5.6) in control, whereas that was the lowest (3.4) under Astragalus membranaceus extract treatment at 35 storage day. The natural exteacts treatments had no effect on the weight, the mositure loss rate, the firmness and the soluble solid contencts of peeled chestnuts during storage after treatment. The decaying rate of peeled chestnut was 9.0% in control, 9.0% in Camellia sinensis extract treatment, 9.0% in Angelica gigas extract treatment, 21.0% in Astragalus membranaceus extract treatment, and 7.0% Glycyrrhiza uralensis extract treatment at 35 storage day. Sensory evaluation revealed significant differences in off-odor and color attributes. After all, the score of overall sensory evaluation was the lowest in Astragalus membranaceus extract treatment and the highest in Glycyrrhiza uralensis extract treatment. As the results, the natural extract treatments, especially with vacuum packing after Glycyrrhiza uralensis extract treatment, extended the shelf-life of the peeled chestnut by inhibiting the surface browning.