• Journal of Korea Water Resources Association
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• v.45 no.5
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• pp.445-454
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• 2012

The present study aims to investigate the long-term channel morphological changes derived from channelization, embankment and levee construction works in unregulated fluvial channel of the Jiseock River. Analyses of aerial photographs taken past (Year 1966) and recent (Year 2002) showed the temporally remarkable changes in channel planform such as channel shape, bar migration, vegetation encroachment in bar. During the period, the natural single threading changed into braided types together with decreasing sinuosity by 9.2%, increasing vegetation occupied bar ranged 97% of total bars area. Because such channel morphological changes are closely similar to those in dam downstream channels, we assume that both/either flow regime alteration and/or sediment transport discontinuity may be critical for the fixed channel and spread of vegetated bars even in unregulated river without dam reservoir upstream. We found more reduced frequency and magnitude of flooding water level comparing with past, but no significant alteration of inter annual water level variation. Bed material has been coarsened by 4~5 times and the riverbed has been degraded in overall channel but aggraded locally in conjunction reach of tributaries. The results indicates that reduced sediment dynamics in fluvial channel which derived by bed material coarsening, river bed degradation and unbalanced sediment transport capacity between tributary and mainstem can be a causal factor to trigger channel morphological changes even in unregulated rivers.

• Journal of Bio-Environment Control
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• v.25 no.3
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• pp.173-176
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• 2016

This research was performed to breed new columnar-typed apple variety for pollinator in apple orchard. We cross-fertilized 'Hongro' that was an ovary parent and 'Maypole' a pollen parent in 2003. We gathered seeds in 2003 and sowed after breaking of dormancy in 2004. Seedlings was been growth and development till flowering. After fruit setting, We investigated characteristics of growth and fruit including mating compatibility from 2010 to 2012, then finally selected '03-2-95' named 'Tinkerbell' in 2012, registered as new variety on Korea Seed & Variety Service in 2015. The full bloom stage of 'Tinkerbell' was later 2 days then of 'Maypole'. Tree habit of 'Tinkerbell' was alike to of 'Maypole', for example weak tree vigor, columnar type. But there were many different characteristics between 'Tinkerbell' and 'Maypole'. Fruit shape of 'Tinkerbell' was ovoid whereas of 'Maypole' was ellipsoid. Fruit of 'Tinkerbell' was bigger, smoother skin, no waxy bloom than of 'Maypole'. Fruit of 'Tinkerbell' was more delicious than of 'Maypole' because of having higher soluble sugar content and lower titratable acidity. 'Tinkerbell' was excellent pollinator in apple orchard. Because of having high fruit setting rate with major apple varieties and a narrow tree width that was advantageous as pollinator in apple high density system.

• Proceedings of the Korean Vacuum Society Conference
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• 1999.07a
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• pp.159-159
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• 1999

니켈 산화물 박막을 전자비임 증착법으로 기판온도는 RT~25$0^{\circ}C$의 범위에서 제작하였다. 제작시 초기 베이스 압력은 2$\times$10-6mbar로 하고 산소주입후 작업진공도를 3$\times$10-4mbar로 유지하여 증착하였다. 제작시 기판온도에 따라 제작된 시료들은 각각 X선회절장치(XRD)로 막의 구조과 그림과 같이 입방체 구조 또는 팔면체구조를 갖음을 알 수 있었으며 막의 표면형상은 SEM을 이용하여 분석하였다. 각각의 여러 기판온도에 따라 제작된 니켈 산화물 박막의 전기 화학적인 특성을 분석하기 위해 순환전압전류법을 이용하였다. 또한, 전기적인 광학소자로써의 특성을 분석하기 위해 UV-Vis 광분광기를 사용하여 투과율을 측정하여 그 특성을 알아보았다. 순환전압전류법에 의한 각 시료에 대한 박막의 전기화학적 특성은 0.5M KOH 전해질 수용액에서 기판온도가 150~20$0^{\circ}C$로 제작된 니켈 산화물 박막이 다른 온도에서 제작된 시료들보다 높은 전기화학적 안정성을 보임을 알 수 있었다. 마찬가지로 광학적 특성에서 착색과 탈색의 순환과정시 분광광도계에서 나타나는 광투과율을 비교해 보면 100~20$0^{\circ}C$에서 제작된 니켈 산화물 박막이 가역적인 착탈색의 색변화가 현저하게 나타남을 알 수 있었다. 결과적으로 광학적 특성 및 전기화학적 안정성 분석으로 인해 막의수명과 전기적착색 물질의 특성면에서 증착시 기판온도가 150~20$0^{\circ}C$에서 제작된 시료가 가장 내구성면에서 막의 이온 누적이 적고 활성적인 광투과율의 성질을 갖는다는 것이다. 이와같이 니켈산화물 박막제작시 기판온도가 전기적착색물질의 특성과 내구성에 큰 영향을 미침을 분석할 수 있었다.electron Microscopy)과 AFM(Atomim Force microscopy)으로 증착박 표면의 topology와 roughness를 관찰하였다. grain의 크기는 10nm에서 150nm이었고 증착막의 roughness는 4.2nm이었다. 그리고 이 산화막에 전극을 형성하여 유전 상수와 손실률 등을 측정하였다. 이와 같이 plasma를 이용한 3-beam에 의한 증착은 금속의 산화막을 얻는데 유용한 기술로 광학 재료 및 유전 재료의 개발 및 연구에 많이 사용될 것으로 기대된다.소분압 조건에서 RuO2의 형성을 관찰하였으며, 이것은 열역학적인 계산을 통해서 잘 설명할 수 있었다.0$\mu\textrm{m}$, 코일간의 간격은 100$\mu\textrm{m}$였다. 제조된 박막 인덕터는 5MHz에서 1.0$\mu$H의 인덕턴스를 나타내었으며 dc current dervability는 100mA까지 유지되었다. CeO2 박막과 Si 사이의 결함때문이라고 사료된다.phology 관찰결과 Ge 함량이 높은 박막의 입계가 다결정 Si의 입계에 비해 훨씬 큰 것으로 나타났으며 근 값도 증가하는 것으로 나타났다. 포유동물 세포에 유전자 발현벡터로써 사용할 수 있음으로 post-genomics시대에 다양한 종류의 단백질 기능연구에 맡은 도움이 되리라 기대한다.다양한 기능을 가진 신소재 제조에 있다. 또한 경제적인 측면에서도 고부가 가치의 제품 개발에 따른 새로운 수요 창출과 수익률 향상, 기존의 기능성 안료를 나노(nano)화하여 나노 입자를 제조, 기존의 기능성 안료에 대한 비용 절감 효과등을 유도 할 수 있다. 역시 기술적인 측면에서도 특수소재 개발에 있어 최적의 나노 입자 제어기술 개발 및 나노입자를 기능성 소재로 사용하여 새로운 제품의 제조와 고압 기상 분사기술의 최적

• Korean Journal of Construction Engineering and Management
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• v.20 no.6
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• pp.66-73
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• 2019

Thanks to various efforts to reduce disasters by the government and the Health and Safety Authority, disasters across industries and the construction industry show their reduction trend. However, the falling disasters in the construction industry have not decreased and increased on the contrary. Especially falling disaster caused by Hanging Scaffolding is the most critical disaster which shows low occurrence frequency but is directly connected to death of worker. The working environment for Hanging Scaffolding is poor in domestic construction site. In particular, the Hanging Scaffolding workers in small construction sites are not on the safety control and management by anyone for their works. They are driven to unsafe working condition with mostly uncertified facilities which are made by themselves. Therefore, this study is focused on searching falling disaster factors from the 242 disaster cases caused by Hanging Scaffolding Work in 15 years presented by KOSHA, and trying to provide suggestions for improvement. The improvement of the method of work requires facility improvement and work due to high accident rate caused by unsafe behavior. Analysis of the case of a disaster occurring over the past 15 years shows that no disaster occurred due to problems in the order of operations presented by KOSHA. However, it was found that many accidents resulted from death caused by safety belts not being installed or attached to ropes using safety belts without following the order of work. The most important aspect of improving the work method was the installation and wearing of lifeboats and safety belts.

• Korean Journal of Soil Science and Fertilizer
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• v.28 no.2
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• pp.114-122
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• 1995

Complexation experiment between humic acid and heavy metal cations was conducted to clear information on heavy metal adsorption by soil organic constituent. The absorbance of UV-visible light of humic acid-metal complexes increased with increasing wavelength, and the order of their absorbance was in the order of Zn->Cd->Cu- saturated humic acid. Carboxyl and phenolic OH groups participated in the complex formation between heavy metal cations and functional groups of humic acid, and the amounts complex was in the order of $Cu^{+{+}}$ > $Zn^{+{+}}$ $\geq$ $Cd^{+{+}}$. The stability constants of humic acid-metal complexes increased with increasing pH, and the order of first stability constants was $Zn^{+{+}}$ > $Cd^{+{+}}$ > $Cu^{+{+}}$, and those of second and overall stability constants were $Cu^{+{+}}$ > $Zn^{+{+}}$ > $Cd^{+{+}}$. With increasing pH, the average binding numbers betwen heavy metal cations and functional groups of humic acid increased the order of $Cu^{+{+}}$ > $Zn^{+{+}}$ > $Cd^{+{+}}$. It was postulated that two types of complexations between heavy metal cations and functional groups of humic acid. One was the reactions in which only carboxyl groups participated to form complexes, and the other was those in which both carboxyl and phenolic OH groups simultaneously participated.

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.1
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• pp.11-18
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• 2004

The eruption of permanent teeth represents the movement in the alveolar bone before appearance in oral cavity, to the occlusal plane after appearance in oral cavity, and additive movement after reaching th the occlusal plane. Tooth eruption is mostly controlled by genetic signals. The eruption stage is divided to preeruptive alveolar stage, alveolar bone stage, mucosal stage according to the process of growth and development. If the disturbance is occured in any stage of eruption, tooth does not erupt. The cause of eruption disturbance are ectopic position of the tooth germ, obstruction of the eruption path and defects in the follicle or PDL. In the treatment of eruption disturbance, surgical procedures are commonly used. There are three kind of surgical procedure ; surgical exposure, surgical repositioning, surgical exposure and traction Surgical exposure is basic procedure. This involves removal of mucosa, bone, lesion that are surrounding the teeth, dental sac when necessary to maintain a patent channel between the crown and the normal eruptive path into the oral cavity. To ensure this patency, many techniques including cementation of a celluloid crown, packing with gutta-percha or zinc oxide-eugenol, or a surgical pack, are used. When surgical exposure is conducted, operators should not expose any part of cervical root cement and not injure periodontium or root of adjunct tooth. After surgical exposure, tooth should be surrounded by keratinized gingiva. There is direct relationship between the extent of development of pathophysiologic aberrations and the intensity of the manipulative injury inflicted on the tooth by surgical treatment, so operator should consider this thing. In these cases, surgical exposure is conducted on Maxillary 1st milars that have a eruption disturbance and improve the eruption disturbance effectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.6
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• pp.1134-1141
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• 2002

Adhesion of leukocytes to the activated vascular endothelium and their subsequent recruitment/migration into the artery wall are key features in the pathogenesis of atherosclerosis and inflammatory diseases. These features have been mediated by cell adhesion molecules including vascular cell adhesion molecule-1 (VCAM-1) and in tracellular cell adhesion molecule-1 (ICAM-1). This study examined whether flavonoids inhibit the pro-inflammatory cytokine TNF-$\alpha$-induced monocyte adhesion via a modulation of the protein expression of VCAM-1 and ICAM-1 of human umbilical vein endothelial cells (HUVECs). TNF-$\alpha$ markedly increased the adhesion of THP-1 monocytes to endothelial cells and induced the expression of VCAM-1, ICAM-1 and E-selectin proteins in HUVECs. Micromolar concentrations of the flavones luteolin and apigenin and the flavonol quercetin near completely blocked the monocyte adhesion to the activated endothelial cells and the induction of these adhesion molecules. However, equimicromolar catechins of (-)epigallocatechin gallate and (+)catechin, the flavonol myr- icetin and the flavanones of naringin and hesperidin had no effect on TNF-$\alpha$-activated monocyte adhesion. (-)Epigallocatechin gallate, (+) catechin, and naringin did not attenuate the TNF-$\alpha$ induction of these adhesion molecules. Furthermore, culture with luteolin and apigenin strongly blocked the expression of TNF-$\alpha$-induced VCAM-1 mRNA and modestly attenuated ICAM-1 mRNA. Quercetin modestly decreased the TNF-$\alpha$-activated VCAM-1 and ICAM-1 mRNAs. These results demonstrate that flavonoids classified as flavones and flavonols may inhibit monocyte adhesion to the TNF-$\alpha$-activated endothelium, most likely due to a blockade of expression of functional adhesion molecules down-regulated at the transcriptional level, indicating a definite linkage between the chemical structure of flavonoids and the expression of cell adhesion molecules. Furthermore, the antiathero-genic feature of flavonoids appears to be independent of their antioxidant activity.

• Journal of Bio-Environment Control
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• v.5 no.2
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• pp.202-209
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• 1996

The environment in composting greenhouse is very different with the traditional greenhouse by biothermal energy and $CO_2$ concentration. This experiment aimed to investigate the environmental effects on the growth and development of tomato grown at composting greenhouse. The room temperature is not different between two greenhouses because of heating and ventilation, but the soil temperature in composting greenhouse is about 7$^{\circ}C$ to 15$^{\circ}C$ higher than that of traditional greenhouse. The emission concentration of ammonia gas is the highest, 117.3ppm, at the 6th day starting the digest, and were gradually lowered from 7th day, 11 became 15.7ppm at the 16th day. The concentration of $CO_2$ in composting greenhouse were 250 to 2000ppm higher than that of traditional greenhouse for 4 months starting digest. The growth and development of tomato grown at composting greenhouse was better than that of traditional greenhouse. The yield in composting greenhouse was also better than that of traditional greenhouse. The sugar contents of tomato grown at composting greenhouse became about 1 $^{\circ}$Brix higher than that of traditional greenhouse.

• Korean Journal of Agricultural and Forest Meteorology
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• v.3 no.4
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• pp.185-198
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• 2001

This study was conducted to reveal the effects of local climatic conditions on reproductive growth in a mature stand of Korean white pine based on climatic estimates. For this, the reproductive growth such as production and characteristics of cone and seed were first measured and summarized for seven years from 1974 to 1980. The local climatic conditions in the study site were also estimated by both a topoclimatological method and a spatial statistical technique. The local climatic conditions were then correlated with and regressed on the growth factors to reveal the relationships between the climatic estimates and the reproductive growth. Average number of conelet formation per tree showed highly negative correlation with some climatic variables related to minimum temperature in the year of flower bud differentiation. Especially, the most significant negative correlation were found between average of the minimum temperature for June and July of flower bud differentiation year and the number of conelet formation. There was no significant correlation between the number of cone production and climatic variables. However, total precipitation from December of the flowering year to February of the cone production year showed the most high correlation (r=0.6036) with the number of cone production. It was found that significant climatic variables affecting the amount of cone drop and cone drop percentage were the sum of cloudy days from June of the flowering year to August of the cone production year. Positive correlation was significantly recognized between the average weight of empty seed per cone and total precipitation from December of the flowering year to February of the cone production year. For the percentage of empty seed, five climatic variables among 19 variables were significantly correlated at 10% level. The average weight of a cone showed negative correlation with total precipitation from June of the flowering year to August of the cone production year. It was also found that average weight of a seed had highly negative correlation with total precipitation from December of the flowering year to February of the cone production year. The average weight of cone coat was negatively correlated with two climatic variables derived from clear days, which are sum of clear days from November of the flowering year to March of the cone production year and sum of clear days from December of the flowering year to February of the cone production year. On the other hand, it showed positive correlation with mean temperature of May in the flowering year. The exactly same results were obtained in correlation analysis for the percentage of cone coat.

• The korean journal of orthodontics
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• v.31 no.1 s.84
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• pp.137-147
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• 2001

Acidic primer is the bonding agent which combines the conditioning and priming agent into the single solution and was originally developed for the dentin bonding system. It is less harmful to the tooth structure and more convenient to manipulate than the traditional etching procedure. The Purpose of this study is to evaluate the shear bond strength of various bonding materials when the enamel is treated with acidic primer for the bracket bonding procedure. Fifty recently extracted human premolars were randomly separated into five groups -Group I using Clearfil Liner Bond 2 adhesive system to the enamel treated with acidic primer, Group II using Transbond XT adhesive system to the enamel treated with acidic primer, Group III using panavia 21 adhesive system to the enamel treated with acidic primer, Group IV using Fuji-Ortho LC adhesive system to the enamel treated with acidic primer, Group V using Transbond XT adhesive system to the enamel treated with 37$\%$ phosphoric acid. The shear bond strength was measured with Instron universal testing machine after storing in $37^{\circ}C$ water bath for 48 hours. After debonding, the teeth and brackets were examined under scanning electron microscope (SEM) and assessed with the adhesive remnant index (ARI). The results were as follows : 1. There were no significant differences in shear bond strength between group III ($8.69{\pm}2.72MPa$), group IV (9.7 ± 3.16 MPa), and group V ($10.48{\pm}2.60MPa$) (p>0.05). 2. The shear bond strength of group III and group IV was significantly higher than that of group I ($1.09{\pm}0.53MPa$), and Group II ($2.70{\pm}1.46MPa$) (p<0.05). 3. The ARI of group IV ($2.1{\pm}1.1$) and group V ($2.9{\pm}0.3$) was significantly higher than that of group I ($0.2{\pm}0.4$), group II ($0.3{\pm}0.9$) and group III ($0.2{\pm}0.4$) (p<0.05). 4. There were no significant difference between the ARI of group IV and group V (p>0.05). This result suggests that the combination of acidic primer and some bonding adhesive can provide sufficient shear bond strength for clinical orthodontics.