• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2004.11a
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• pp.47-53
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• 2004

Water vapor is an important parameter in monitoring changes in the Earth's climate and it can be used to improve weather forecasting However, it haven't observed accurately by reasons of structural and economic problem of observation. GPS meteorology technique for precipitable water vapor measurement is currently actively being researched an advanced nation. Main issue of GPS meteorology is an accuracy of PWV measurement related weighted mean temperature and meteorological data. In this study, the korean weighted mean temperature had been recalculated by a linear regression method based on meteorological observations from 6 radiosonde stations for 2003 year. We examined the accuracy of PWV estimates from GPS observations and Radiosonde observations by new korean weighted mean temperature and others.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2014.11a
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• pp.80-81
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• 2014

환경보호 정책에 대응하고 보건 및 안전의 수준 향상을 위한 수용성 도료의 적용 시, 일부 도장 공정에서 도막 건조의 지연으로 sagging 현상이 발생하였다. 이러한 sagging 현상이 일어난 원인을 실험을 통해 분석한 결과, 도료가 갖는 고유의 yield stress와 더불어 습도 및 통기 상태 등의 시공 환경이 지배적인 영향을 미친다고 파악되었다. Sagging 현상의 재발을 방지하기 위해서는 높은 sagging 저항성을 갖는 도료의 선정뿐만 아니라 도장 공장의 적절한 온/습도 및 환기 제어가 선행되어야 한다.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2014.11a
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• pp.83-83
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• 2014

선박건조에 사용되는 도료 중 SPC(self-polishing copolymer) A/F(anti-fouling) 도료의 주된 기능은 해양생물의 부착 등 해양생물에 의한 오염을 방지하는 방오성능으로 인식되어 왔으나, 최근 방오성능 뿐 아니라 선박의 운항 시 선체저항을 줄임으로써 발생되는 연료절감효과와 선박의 미관을 위한 변색지연 등 SPC A/F 도료의 다른 기능에 많은 관심을 가지게 되었다. 이러한 관심과 사용자의 요구에 따라 도료사에서는 항력의 감소를 가져 올 수 있는 Silyl acrylate copolymer로 디자인 된 Silyl acrylate SPC A/F 도료를 개발하였으나 SPC A/F 도료의 방오제(biocides) 종류에 따른 방오성능 차이를 비교 평가 할 수 있는 객관적 자료가 부족하여, 본 연구를 통해 SPC A/F 도료의 종류 별 방오성능을 평가하고자 한다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.12
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• pp.1972-1980
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• 2013

The purpose of this study is to evaluate the storage quality characteristics of bread with added dried mulberry pomace (DMP, 0, 1, 3 or 5%) during storage at $4^{\circ}C$ for 7 days. During the entire storage period, the moisture content was higher in breads containing DMP compared with the control bread. Textural properties by TPA showed that the hardness of DMP bread maintained a lower hardness than that of the control during the entire storage period. Moreover, DSC (Differential Scanning Calorimetry) result showed that ${\Delta}H$ (crystal melting enthalpy) of the bread containing DMP was lower than that of the control bread, which indicate the retarding of retrogradation. The sensory preference test results demonstrated that the bread with 3% DMP had higher scores in over-all preference than the others. These results suggest that DMP delays the retrogradation of bread during storage.

• Journal of the korean academy of Pediatric Dentistry
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• v.34 no.2
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• pp.192-203
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• 2007

This study histologically assessed the effect of topical alendronate application on periodontal healing in replanted teeth in fifty four SD Rats. Upper first molars in rat were extracted and replanted after dried during 15 minutes or 60 minutes in the air. In Group I, all teeth were replanted after 15 minutes of dry storage without any other treatment. In Group II and III, the pulps were removed and all teeth were replanted after soaking 10 min in Hank's balanced salt solution with/without alendronate, followed by 60 minutes of dry storage. the rats were sacrificed after 7, 15 and 30 days. The histological parameters studied were healed PDL, surface inflammatory and replacement resorption, and inflammatory severity. The following conclusions could be drawn from the present investigation. 1. Group I showed lower inflammatory root resorption and inflammation severity rate, compared to Group II and Group III. In Group I there showed effective for reattachment and regeneration of PDL. 2. In Group II, inflammatory root resorption were more severe and faster than other groups. There were extensive root resorption in the rats sacrificed after 30 days. 3 In Group III, there were localized inflammatory resorption in several areas, but extensive resorption did not occur Group III showed increase in root resorption rate, compared to Group I. However this difference was not statistically significant. 4. There were no difference between sacrificed days in replacement root resorption in all groups.

• Journal of the Korean Wood Science and Technology
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• v.37 no.6
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• pp.537-545
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• 2009

The objective of this study was to investigate potential usage of environmentally friendly building materials, liquid mortar and dry cement mortar mixed with charcoal, based on the test of their physical and chemical properties. From the test results of physical and chemical properties of the liquid mortar mixed with charcoal, liquid mortar containing over 20% of charcoal, the consistency viscosity and the non-volatile content met a standard requirement. Drying time was delayed with increase in charcoal contents in the liquid mortar, however they were fully cured within 60 minutes in all treated levels. Other properties were acceptable at standard requirement. From the results, it was found that the proper charcoal addition level to the liquid mortar was 25%. In the results on dry cement, it was found that samples containing 5% of charcoal showed the maximum compressive strength, whereas samples containing over 20% of charcoal did not reach the minimum requirement of KS standard. Water retention ability constantly increased as the charcoal ratio increased. The conventional dry cement mortar adsorbed 59.5% of it, in the test of adsorption rate on ammonia gas, whereas cement mortar containing 10% of charcoal showed 71.6% of ammonia gas adsorption.

• Journal of the korean academy of Pediatric Dentistry
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• v.46 no.3
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• pp.274-282
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• 2019

The purpose of this study was to evaluate effect of saliva decontamination procedures on microtensile bond strength (MTBS) of 1-step self-etching adhesives to dentin of primary posterior teeth. 63 sound primary-posterior teeth were randomly divided into 3 groups according to different kinds of 1-step self-etching adhesives: $Scotchbond^{TM}$ Universal Adhesive (SBU), All-Bond $Universal^{(R)}$ (ABU), and $Tetric^{(R)}$ N Bond Universal (TBU). Each group was randomly categorized into 7 subgroups: (I) application of adhesive without saliva contamination (control); (II - IV) contamination by saliva before photopolymerization; (V - VII) contamination by saliva after photopolymerization; (II, V) decontamination by drying; (III, VI) decontamination by washing and drying; (IV, VII) decontamination by washing, drying, and reapplication of adhesive. All samples were cut into the blocks. At least 15 blocks were tested for each subgroup. For SBU and ABU, the MTBS values of subgroups (I, IV, VII) were significantly higher than those of subgroups (II, III, V, VI). For TBU, the MTBS values of subgroups (I, IV) was significantly higher than those of subgroup (II, III, V, VI). The MTBS of 3 adhesives was reduced by saliva contamination. The adhesive strength on dentin of primary posterior teeth was restored by reapplication of the adhesives after washing and drying.

• FLOWER RESEARCH JOURNAL
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• v.17 no.2
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• pp.106-113
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• 2009

Germination percentage of Korean native lily seeds was high at $20-25^{\circ}C$. It was almost 100% in L. cernuum, L. callosum, L. amabile, and L. concolor, 88.0% in L. lancifolium, and 73.0% in L. maximowitzii, respectively. Meanwhile, it was low rate of 34.0%-54.0% in L. distichum, L. hansonii, and L. tsingtauense. Germination was mostly delayed of $15^{\circ}C$ and days to germination were more shortened in species with higher germination percentage. Even though the effect of daylength was not considerable in germination rate, it was promoted in L. maximowitzii but it was delyed in L. hansonii under long day. The effect of soaking in hot PGRs solution in L. callosum, L. cernuum, L. amabile, L. lancifolium, and L. concolor did not show any difference in comparison with non-treatment. However, it was improved by BA in L. maximowitzii. Longer period of cold wet storage resulted in improved germination percentage in L. maximowitzii and L. lancifolium, while it affected decreased percentage in L. distichum and L. hansonii. Days to germination were shortened by longer period of cold wet storage regardless of species. Germination percentage in dry storage was higher under cold temperature than room temperature and under desiccator storage than outside desiccator, it was highest under desiccator storage at $4^{\circ}C$. It was drastically reduced by the non-use desiccator storage at room temperature L. concolor, however it was improved only by the use of desiccator L. maximowitzii for a long time.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.66 no.4
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• pp.318-325
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• 2021

The objective of this study was to identify the effect of zebularine, a DNA methylation inhibitor, on the chromosomal association between homoeologous chromosomes in the wheat genetic background. Zebularine at a final concentration of 10 µM was used to treat the spikes of the double monosomic wheat addition line (DMA) with one Leymus mollis chromosome and one Leymus racemosus chromosome, both of which were in a homoeologous relationship. In late prophase, zebularine led to chromosome breakage in the Leymus homoeologous chromosomes. Chromosome breakage caused an increase in the frequency of chromosomal associations between the Leymus homoeologous chromosomes. Ordinary DMA showed 65 cells (35.3%) with chromosomal associations and 119 cells (64.7%) with no association, whereas treated DMA showed 102 cells (60.0%) with chromosomal associations and 67 cells (39.4%) with no association. In diakinesis, the Leymus bivalent showed a chromosomal association in the whole euchromatic region. In metaphase, the Leymus bivalent showed association in the whole chromosomal region, unlike other Leymus bivalents with partial chromosomal association. Chromosomal association by chromosome breakage occurred not only between Leymus chromosomes but also between Leymus and wheat chromosomes. The frequency of other chromosomal association (such as fusion and insert) was increased. Chromosome breakage by zebularine treatment is a useful method at the chromosome level as the spores with others are hereditary stable, although the homologous index (h) was not significantly different between ordinary DMA and treated DMA. It is necessary to study how to control zebularine treatment with a more stable concentration for chromosome breakage during meiosis.

• Journal of the Korea Concrete Institute
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• v.19 no.5
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• pp.539-547
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• 2007

The effects of binder and alumina content on the setting time, drying shrinkage, strength, freezing and thawing resistance and water absorption of polymer-modified pastes with alumina powder were examined. As a result the setting time of the polymer-modified pastes with alumina powder tended to delay with increasing binder content. Irrespective of the type of polymer, the drying shrinkage of the polymer-modified pastes with alumina powder tended to decrease with increasing binder content and alumina powder content. Regardless of the type of polymer, the tensile and adhesion strengths of the polymer-modified pastes with alumina powder tended to increase with increasing binder content and alumina powder content. Irrespective of the type of polymer, the durability factors of the polymer-modified pastes with alumina powder tended to increase with increasing alumina content. Irrespective of the type of polymer, the water absorptions of the polymer-modified pastes with alumina powder tended to decrease with increasing binder content and alumina content.