• Geophysics and Geophysical Exploration
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• v.18 no.4
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• pp.171-180
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• 2015

Electrical resistivity of 23 core samples from Ulleung Island at dry or saturated condition has been measured along with dry density and effective porosity, and the relations between the properties has also been discussed. Upper and lower bounds of electrical resistivity at room temperature can be provided by the dry- and saturated-resistivity, respectively. Injecting nitrogen gas to the pore space at the very end of drying process can prevent humid air from getting into the pore space, so that measurement of dry-resistivity can be less affected by humidity in the air. Dry density and porosity have very close correlation; the ratio between increase of porosity and the decrease of density showed distinct relation to the rock types, such that basaltic rocks showed higher ratio while trachytic rocks showed lower. Saturated resistivity showed close correlation to density and effective porosity of the rock sample, while dry resistivity didn't.

• Korean Journal of Poultry Science
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• v.15 no.1
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• pp.45-51
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• 1988

This experiment was conducted to determine yolk addition level for manufacturing the seasoned yolk Products. They were Prepared with 0, 10, 20, 40% yolk content in conduction with fish meat faste and spices. Yolk mixture was cooked at $90^{\circ}C$ for 1 hour and then dried with hot air at 5511 for 5 hours. The texture of non-dried seasoned product added with 10% yolk was remarkably increased as compared with any other treatment. For the drying process of seasoned yolk product, the more addition of egg yolk to the mure resulted in a slight difficulties on drying. As yolk level increased in dried seasoned product (egg jerky), moisture and fat content increased whereas protein and total amino acid content decreased. Most of amino acid except leucine, isoleucine and phenylalanine decreased by increasing level of egg ye The Predominant amino acids were glutamic acid, aspartic acid and lysine but only small amount of proline was detected in each treatment. Results of experiment indicated that yolk could be used up 20% level in view of physicochemical and sensory quality in seasoned products.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.2
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• pp.130-136
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• 1987

The studies were carried out to investigate the occurrence of excessive dried leaves during burley tobacco curing. Six different periods of ventilation during the entire stage of curing were applied. And also 3 different heights of rolling up polyethlene film for side ventilation of the curing house combined with 4 different spaces between garlands were applied from after yellowing. The high air temperature and low relative humidity from end of yellowing to end of browning stage were the most critical to occur excessive dried \eaves. As side ventilation was continued for the entire stage of curing, air temperature in curing house was lower and occurrence of excessive dried leaves were remarkably decreased. The air temperature was not affected on hanging spaces, but relative humidity that resulted significantly in decreasing of the excessive dried leaves was increased by narrowing of hanging spaces. As excessive dried leaves were increased, its price per kg was lower, its physical properties was worse and its total nitrogen and total suger were higher than those of normal cured leaves.

• Journal of the Korea institute for structural maintenance and inspection
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• v.14 no.1
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• pp.102-108
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• 2010

The main objective of this study was to evaluate the effect of recycled PET (RPET) fiber made from waste PET bottles to examine application on concrete member. To evaluate the reinforcement effect of RPET fiber in concrete member, experimental tests were performed, such as mechanical property tests (compressive strength, modulus of elasticity and splitting tensile strength) and drying shrinkage test. In mechanical property tests, compressive strength and modulus of elasticity in concrete mixed with RPET fiber gradually decreased, but splitting tensile strength gradually increased as volume fraction of fiber increased. In drying shrinkage test, free drying shrinkage increased. In restrained case, in contrast, crack occurrence was delayed because of tensile resistance increase by RPET fiber. The comparison of RPET and PP fiber added concrete specimen's properties showed that two materials had similar properties. In conclusion, RPET fiber is an alternative material of PP fiber, even finer for its excellence in eco-friendliness due to the recycling of waste PET bottles and its possible contribution to the pollution declination.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1994.05a
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• pp.98-102
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• 1994

천연가스의 주성분인 순수 메탄에 대한 촉매 산화반응은 Pd촉매가 가장 양호하나 LP가스의 주성분인 프로판에 대해서는 Pt촉매가 가장 양호한 결과를 보였다. 그러나 유황 피독된 Pd촉매는 메탄에 대해 영구피독 현상을 보였고, fresh한 Pd촉매는 연료 중 미량의 유황분량에 의해 반응 개시온도가 지연되는 경향을 보였다. 이와 같은 촉매독 영향이 적은 Rh촉매버너를 개발하여 8000시간 이상 성공적인 연소 실험을 하고 있으며 C 방적의 염색 시험기에 적응 실험한 결과 기존의 적외선 전기 건조기에 비해 에너지 절감은 약30-40%를 기하였고 연료비는 70-80%의 절약효과를 얻었다.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1994.05a
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• pp.102-103
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• 1994

원예작물의 개화는 일장이나 생장조절제 처리 이외에도 광도, 관수량, 그리고 시비수준 등 재배환경에 따라 영향을 받는다. 차광처리는 광합성률을 낮추어 개화를 지연시키며, 관수처리는 건조시 양분흡수가 저해되거나, 수분부족 자체가 스트레스로 작용하여 종자생산을 촉진시키는 생식생장으로의 전환을 유도할 가능성도 있다. 쑥갓은 국내에서 엽채류로 4계절을 통해 많이 이용되나 개화생리에 대한 연구가 미비하다. (중략)

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1998.05a
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• pp.131-139
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• 1998

여름철 고온기를 지나는 하우스 밀감은 착색이 되기 전에 과육이 선숙되는데, 일반적으로 착색은 고온에 의해 지연된다(Goldschmidt, 1988). 소비자들은 충분히 착색되지 않고 녹색을 띤 밀감은 성숙이 안된 것으로 생각하고 있기 때문에 수확 후 에테폰 처리에 의해 착색을 촉진시키고 있으나(Jimenez-Cuesta 등, 1983) 과경부의 꼭지가 쉽게 건조되고 짙은 오렌지색으로 발색되지 않고 연한 노란 색으로 되어 상품성이 높지 못하다. (중략)

• Korean Chemical Engineering Research
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• v.55 no.3
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• pp.313-321
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• 2017

We aimed to develop commercialization process of encapsulation which is superior in productivity compared to existing methods by using sodium alginate. Also, in the same process, sodium alginate with chitosan was used to encapsulate lactic acid bacteria with the same process and then the viable cell counts of the two encapsulated lactic acid bacteria were compared. As a test result of the fluidized drying process developed by the present researchers, it was found that the drying time was shortened by 15 to 20 hours compared to the freeze drying method, but the number of viable lactic acid bacteria was about 75% as compared with freeze drying. However, considering the cost and time of drying, it can be confirmed that the commercialization process is possible by the fluidized bed drying method. When the number of viable cells of Ca-alginate capsule and Chitosan-alginate capsule were compared, it was confirmed that there were about $1{\times}10^9$ or more bacteria in the former and about $1{\times}10^3$ in the latter. The lactic acid bacterium capsules prepared by the present technique were stable for 96 hours or more at pH 4.65 and 6.01, but disappeared within 1 hour at pH 7.07 and 8.35. This suggests that the disintegration of lactic acid bacteria can be easily occurred in small and large intestine.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.6D
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• pp.1033-1041
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• 2006

In this study, we calculated a space-time variation of GPS precipitable water vapor using GPS meteorology technique during a progress of the typhoon EWINIAR had made an effect on Korean peninsular at 10 July, 2006. We estimated tropospheric dry delay and wet delay for one hourly using 22 GPS permanent stations and precipitable water vapor was conversed by using surface meteorological data. The Korean weighted mean temperature and air-pressure of versa-reduction to the mean sea level have been used for an accuracy improvement of GPS precipitable water vapor estimation. Finally, we compared MTSAT water vapor image, radar image and precipitable water vapor map during a passage of the typhoon EWINIAR.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.37 no.1
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• pp.1-7
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• 2019

In this study, we estimated the tropospheric delay of GNSS (Global Navigation Satellite System) signals during passing through the atmosphere in relation to weather and seasonal factors. For this purpose, we chose four CORS (Continuously Operating Reference Station) stations from inland (CCHJ and PYCH) and on the coast (GEOM and CHJU). A total of 48 days for each station (one set of data for each week) were downloaded from the NGII (National Geographic Information Institute) and processed it using the scientific GNSS software. The average tropospheric delays in winter are less than 2,400 mm, which is about 200 mm less than those in summer. The estimated tropospheric delay shows a similar pattern from all stations except the absolute bias in magnitude, while a large delay was observed for the station located on the coast. In addition, the delay during the day was relatively stable in winter, and the average tropospheric delay was strongly related to the orthometric height. The inland stations have tropospheric delays by the precipitation rather than humidity due to dry weather and difference in temperature. On the contrary, it was primarily caused by the humidity on the sea. The correlation between temperature and water vapor pressure is 0.9 or larger for all stations, and the tropospheric delay showed a high linear relationship with temperature. It is necessary to analyze the GNSS data with higher temporal resolution (e.g. all RINEX data of the year) to improve the stability and reliability of the correlation results.