• The Korean Journal of Ecology
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• v.26 no.1
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• pp.39-47
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• 2003

The leaf aqueous extracts from five gymnosperms plant were investigated for allelopathy with five Hibiscus syriacus varieties. The leaf aqueous extract of Pinus rigida had the highest total phenolic compound of 2.21mg/L, whereas the soil under Pinus koraiensis canopy had the highest total phenolic compound of 1.38mg/L. Fourteen phenolic compounds were isolated from five gymnosperm plants by HPLC. Among them, phenolic compounds were the highest in P. rigida (320.56 g/mg) with the primary compound 5-sulfosalicylic acid (312.55 g/mg). The correlation between leaf total phenolic compound and pH was not significant, while the total phenolic compound of the leaf extract changed soil pH. The relative seed germination of H. syriacus varieties showed 25% was threshold concentration. The germination rates of varieties were similar to the control group or showed slight stimulation to treatment of P. koraiensis extract. H. syriacus Cambanha was similar to the control group or showed stimulation in all treated groups. H. syriacus Seohohyang showed stimulation in both root and shoot growth compared to the control group. In other varieties except Seohohyang, shoot growth was similar to the control group, while root growth was stimulated in all treated groups. The extracts of tested gymnosperms showed significantly more stimulation to transplanted Seohohyang seedlings, whereas others were similar to control or inhibited in the greenhouse. The dry weight of Seohohyang was greater in all treated groups than the control group, while other varieties were inhibited. All gymnosperm extracts stimulated the chlorophyll contents of Seohohyang and H. syriacus Koyoro but other varieties were not significantly affected. Accordingly, it is suggested that Seohohyang seems the most desirable when planted within these five gymnosperms.

• Journal of the Korea Organic Resources Recycling Association
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• v.8 no.3
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• pp.73-80
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• 2000

The objective of study was to evaluate the apropriate maturity indices for garbage composting using sawdust as bulking agent. Materials used in this study were the average composition garbage(G20) and garbage conditioned by sawdust(GS30, GS50) and cereals(GSC30). Indices for evaluating maturity were VS, water soluble TOC, polysaccharide, Humification Index(HI), and E4/E6. Experiment results showed that VS reduction was the most desirable index for evaluating compost maturity except for the GS50 which were conditioned with high sawdust Water soluble TOC decreased rapidly during the composting of first one month and then little changed. Therefore, water soluble TOC was recommended as maturity index. Polysaccharide was considered as a maturity index in case of garbage conditioned with sawdust and high cereals. Humification Index(HI) and E4/E6 were available as maturity indices in case of only some garbage composting so additional study was needed to confirm them as maturity indices for all garbage composting. Correlation analysis indicated that indices for evaluating maturity of garbage(about 30 C/N ratio) adding sawdust as bulking agent and high cereals, were VS reduction, water soluble TOC, polysaccharide, and E4/E6.

• Journal of Educational Research in Mathematics
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• v.18 no.4
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• pp.455-467
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• 2008

We need to reflect the establishment of meaning and level of 'proof and argumentation in middle school mathematics'. It should be considered as human activity through communication in community. Thus, we should design instruction from this standpoint. From this point of view, we had been operated 'Geometry Inquiry Class' aimed at middle school students in eighth grade for two years to improve current geometry class in middle school. In this study, we will observe how individual students' original proof schemes are developed and accepted to the class through the process of mutual negotiation between the teacher and students. The episode with four phases begins with the initial proof schemes students have offered. Through the negotiation of class participants, it gives birth to the proof scheme unique to the current geometry classroom. Why do we pay attention to the process? It is because we think that the value of this type of instruction lies in the process of communication and mutual understanding and mutual reference, not in the completeness of the final product. This is the very appropriate proof in the middle school mathematics classroom.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.11
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• pp.640-647
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• 2016

By minimizing fluorescence interference phenomena, aequorin-based luminescence technology can provide a relatively sensitive detection platform with integration of $G{\alpha}16$ protein in order to track internal calcium mobilization by G protein-coupled receptors (GPCR). In this type of cell-based functional assay format, it is essential to optimize the transfection process of a receptor and $G{\alpha}16$ protein. For this study, corticotropin releasing factor receptor subtype 2(CRF2) was set as a model system to generate three stable cells with CRF2 and $G{\alpha}16$ in addition to transiently transfected cells under three different conditions. Agonist (sauvagine) and antagonist (K41498) responses in those cells were analyzed to develop the optimum transfection process. As a result, the effective signal ratio in the dose response experiments of sauvagine and K41498 were at least 10-fold higher (z'=0.77) in CRF2-$G{\alpha}16$ stable cells. For the transient transfection cells, stable expression of $G{\alpha}16$ prior to the CRF2 represented a two-fold higher signal (z'=0.84) than the other cases of transient transfection. In conclusion, for the utilization of transient transfection processes to develop a cell-based GPCR functional assay system, it is suggested to introduce various target receptors after stable expression of $G{\alpha}16$ protein.

• Journal of Conservation Science
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• v.25 no.2
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• pp.147-154
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• 2009

The change of strength and water vapour diffusion resistant by soluble salts was investigated in the tuff and granite used in many stone monuments of Gyeongju area. With $Na_2SO_4$ and $CaSO_4{\cdot}2H_2O$ were treated the rock samples to understand the difference of solubility. The densities of the tested rocks were increased by the impregnation of $CaSO_4{\cdot}2H_2O$ and $Na_2SO_4$. The flexural strength was increased in the tuff samples but decreased in the granite as the salts increased in the pore. In the tuff, the uniaxial compressive strength was increased by $CaSO_4{\cdot}2H_2O$, but decreased by $Na_2SO_4$. In the granite, it was decreased slightly by $CaSO_4{\cdot}2H_2O$, but increased by $Na_2SO_4$. The water vapour diffusion resistant was increased by the salts in both rocks. As results, it was cleared that the mechanical strength colud be increased in early stage of weathering by the accumulation of salt and water vapour diffusion resistant.

• Journal of Conservation Science
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• v.26 no.4
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• pp.397-406
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• 2010

The most ideal method to measure the water-soluble $Cl^-$ ion eluted from iron artifacts is conducting the analysis on desalting solution by Ion Chromatography. But most institutes related to cultural heritages use Cl meter by reason of lack of budget and experts. This study evaluated reliability and stability between Cl meter and Ion Chromatography by doing cross-validation with results from two methods to detect $Cl^-$ ion of desalting solution. From D.I water, extremely small quantities of $Cl^-$ ion was detected by the influence of remaining water-soluble $Cl^-$ ion at the electrode of Cl meter and water-soluble $Cl^-$ which remains in Sodium sesquicarbonate, components of reagent was detected as well. The first desalting solution had the most $Cl^-$ ions, $Cl^-$ ion slightly decreased from the second to the fourth desalting solution and tend to decrease again at the stage of dealkalified in D.I water. Each Cl meter has the standard deviation according to the measured numbers and the higher concentration of $Cl^-$ ion the desalting solution has, the wider the deviation is. But when the concentration of $Cl^-$ ion is low, it was stable to use Cl meter to detect the concentration of $Cl^-$ ion from iron artifacts because there is the small deviation, It is thought that conductivity meter method is not suitable for measuring $Cl^-$ ion, because the electrical conductivity of alkaline solution is too high to measure $Cl^-$ ion.

• Journal of Wetlands Research
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• v.17 no.4
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• pp.339-347
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• 2015

Differences in characteristics of flora and environmental factors of geomorphology, hydrology, water quality and soil were investigated in the shoreline of total 35 reservoirs according to their usages of waterpower generation, agricultural water supply, residential and industrial water supply and flood control in Korea. The number of plant species, floral structure and characteristics of species traits in the shoreline of reservoirs were different according to their usage. From the results of stepwise regression analysis, the total number of vascular plant species was increased at the environment of the higher flood frequency at the median water level and the longer exposure duration of the shoreline. The results of principal coordinates analysis and cluster analysis showed that the shoreline flora was classified as the 3 types of 1) flood control and residential and industrial water supply, 2) agricultural water supply and 3) waterpower generation reservoirs. The water level fluctuation, flood frequency at the median water level, lake water quality index and exposure duration of the shoreline were selected as important environmental factors affected on the characteristics of shoreline flora. The species richness of total flora and hydrophytes, especially submerged macrophytes, were much higher in the reservoirs for the purpose of the waterpower generation in which mesotrophic water quality and stable water levels were maintained. Annual or biennial ruderals were established on the ephemeral drawdown zone of flood control, residential and industrial water supply reservoirs which have oligotrophic or mesotrophic water quality and wide range of water level fluctuation. The floating hydrophytes were differentially dominated in the littoral zones of the agricultural water supply reservoirs with a mesotrophic or eutrophic water quality and a medium water level fluctuation. In conclusion environmental factors related to water level fluctuation and water quality were different and then the floral characteristics of shoreline were distinguishable according to usage of Korean reservoirs.

• Journal of Digital Convergence
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• v.19 no.3
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• pp.217-225
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• 2021

This study analyzed the perception formed by artificial intelligence users by converging technology readiness index and technology acceptance models and expanding them to models considering artificial intelligence ethics in order to find out the impact of technology acceptance and ethics. Independent variables include optimism, transparency, ethical awareness, user-centeredness, perceived usefulness and perceived ease of use as potential variables affected by independent variables, and defined the intention of use as potential variables as dependent variables. The survey results from an online and offline of men and women aged over 17 years old across the country (N=260) from September 5 to October 12, 2020 were used in the analysis. The findings, first, showed that optimism had a significant static effect on perceived usefulness and ease of use. Second, ethical awareness (transparency, ethical awareness, user-centeredness) did not have a significant impact on perceived usefulness and ease of use. Third, perceived usefulness and ease of use are finally found to have a significant static effect on the intention of use. Fourth, perceived usefulness has a relatively high influence over ease of use.

• Proceedings of the Korean Aquaculture Society Conference
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• 2003.10a
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• pp.118-118
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• 2003

홍조류 김속 해조 5종(모무늬돌김, 방사무늬김, 참김, 긴잎돌김, 잇바디돌김)의 사상체를 2단계 냉각법으로 액체질소 중에서 동결보존을 시행하였다. 시료를 여러 가지 동해보호제에 현탁시킨 후 프로그램 냉각기로 4시간에 걸쳐 -4$0^{\circ}C$까지 천천히 동결시켰다. 일차 완만동결 종결 후 즉시 동결용 튜브를 액체질소 중에 수용하여 급속동결 시켰다. 해동시에는 4$0^{\circ}C$의 항온수조에서 대부분의 얼음 결정을 급격히 해동시킨 후 냉각수내에서 완전히 해동시켰다. 생존률은 김 속 해조에서는 neutral red로 염색하여 산정하였으며 50% 해수에 10% DMSO와 0.5M sorbitol 혼합액을 동해보호제로 사용하였을 때의 생존율이 54.6~70.9%였다.

• Electronics and Telecommunications Trends
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• v.10 no.4 s.38
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• pp.85-98
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• 1995

ITU-T의 차세대지능망 표준화는 최초의 진화단계인 IN CS-1이 '95 SG11 회의에서 완결되었고, 현재는 IN CS-2/3 표준화에 대한 논의가 진행되고 있다. IN CS-2는 일부 IN CS-1 목표서비스의 국제연동, FPLMTS의 지원, 서비스관리/생성 서비스의 제공 등의 요구사항을 수용하되 FPLMTS와 서비스 관리/ 생성 서비스와 관련해서는 분산기능평면까지만 부분적으로 권고한다. 본 고에서는 현재 표준화 주요 대상인 IN CS-2에 대하여 분석하였다.