• Korean Journal of Pharmacognosy
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• v.35 no.1 s.136
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• pp.62-79
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• 2004

Cell-scattering is a phenotypic change easily observed in most epithelial cells treated with Hepatocyte Growth Factor /scatter Factor (HGF/SF) or phorbol esters (PKC-activators). Recent studies have shown the possibilities to use as therapeutic materials of HGF/SF or non tumor promoting phorbol esters for liver disease, cancer and AIDS. In this study, we tested a cell-scattering activity of 534 methanol extracts from plants inhabiting in Korean peninsula using the phenotype-based assay system. Nine Active extracts were detected : Daphne genkwa, Daphne kiusiana, and Aleurites fordii showed high activity (+++), Euphorbia sieboldiana and Rhodotypos scandens showed medium activity (++), Sambucus sieboldiana var. pendula, Catalpa bignonioides, Sambucus sieboldiana and Lycoris squamigera showed low activity (+). Furthermore, the effects of these active materials in the culture cells were investigated with biochemical studies.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.572-575
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• 2004

A fundamental study was executed in order to evaluate quantitatively the effect on strength characteristic of concrete or mortar by fly ash. As a result, it was confirmed that the appropriate usage of fly ash is in existence comply with mix condition and characteristic of fly ash. And, we could evaluate the activity factor of fly ash. But, there are many problem in actual application because that the object of this study is only Method(2) out of the evaluation methods of activity factor proposed by CEN. Therefore, it is necessary to keep up an additional study.

• East Asian mathematical journal
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• v.28 no.2
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• pp.173-195
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• 2012

The purpose of this study is to help for an in-depth understanding of their thinking process by observing and analyzing the response found by two elementary school students, Through this study, the following findings could be obtained. First, two students have a tendency trying to solve the complex situation at first. Second, we could know that it is an important factor in discovering the pattern to predict it. Third, we could know that the activity of reconstructing the data meaningfully is an important factor in discovering the pattern. Fourth, it is an important factor in finding the pattern to work organically the activity of predicting it with the activity of reconstructing the data meaningfully. We hope that this study offers the help for an in-depth understanding of students's thinking process.

• Proceedings of the Korea Database Society Conference
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• 2008.05a
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• pp.307-320
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• 2008

This study finds out the influence factor of knowledge sharing based on the viewpoint of the relationship central knowledge and inquires out the relationship between knowledge sharing and a knowledge activity performance. The related factor is set trust, openness communication and cooperation as independent variables. And the knowledge activity performance is set knowledge quality and user knowledge satisfaction as dependent variables which are influenced by knowledge sharing. This study proposes that to improve the organizational performance needs to manage not only knowledge, but also the users and surroundings.

• Natural Product Sciences
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• v.11 no.3
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• pp.131-135
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• 2005

Methanolic extracts of ninety-five medicinal plants were screened for platelet-activating factor (PAF) receptor binding inhibitory activity using rabbit platelet. Alpinia officinarum, Belamcanda chinensis, Leonurus heterophyllus, Pinus densiflora, Polygonatum sibiricum and Sambucus williamsii showed significant inhibitory effects on the platelet-activating factor (PAF) receptor binding.

• Journal of the Korean Institute of Landscape Architecture
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• v.37 no.6
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• pp.73-84
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• 2010

The urban representative landscapes play a leading role in establishing city identity via a symbol of the city and a mediator to make the city all the more worthy of being peculiarized. The study aims at evaluating the perceptive factors in the representative landscapes around the metropolitan Seoul derived from the preliminary researches through questionnaire surveying, in an attempt to analyze their characteristics by type and reason, while further proposing progressive management plans. This study was mostly focused on the visibility factor, activity factor, aesthetic factor and cultural factor influencing on the cognition of urban representative landscapes. The important findings discovered in this research are as follows. First, it was found that people were being interested more on the cultural factors and the activity factors these days rather than visibility factors in the cognition of urban representative landscapes. Second, it was found that the priority rank of urban representative landscapes revealed in this study based on the total account of more diverse perceptive factors, showed so much alteration compared to the previous researches focused mostly upon the visual image.

• Asia-Pacific Journal of Business
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• v.11 no.2
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• pp.189-206
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• 2020

Purpose - The purpose of this study is to clarify the mediating effect of profitability and activity in the relationship between productivity and stock return, assuming that the productivity of the company will affect share prices with the parameters of profitability and activity. Design/methodology/approach - The study extracted productivity indicators, profitability indicators, activity indicators, and share price-related indicators from 1999 to 2018 of non-financial enterprises listed on the securities market, and then classified them into three factors: productivity (labor productivity LP, capital productivity CP), activity (TT), and profitability (net profit rate NI, operating profit ratio OI) through the factor analysis method, and analyzed the impact of each factor on the stock return through steps 1 to 3. Findings - The regression analysis shows that productivity has a significant positive effect on the stock return through the full mediating effect of profitability and activity. Research implications or Originality - In a situation where the relationship between productivity and profitability is not clear, this study is meaningful in that it has empirically analyzed that productivity has a positive effect on the stock return by mediating effects of profitability and activity.

• Microbiology and Biotechnology Letters
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• v.31 no.4
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• pp.395-399
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• 2003

Nebramycin is a complex of aminocyclitol compounds that is produced by aerobic culture in fermentation process. The major antibiotic factors produced by Streptoalloteichus hindustanus are nebramycin factor 2, 4, 5'and kanamycin A. A mutant was selected, producing nebramycin factor 5' activity 16.4 times higher than parent strain by microbiological assay using Pseudomonas aeruginosa CH-U34AF. The component ratio of nebramycin factor 5' was dramatically increased from 34% to 70% by the optimization of fermentation condition. It was found that the component ratio of nebramycin factor 5' in fermentation was especially affected by the oxygen transfer rate. Optimum oxygen transfer rate for maximal nebramycin factor 5' productivity and ratio during S. hindustanus fermentation was elucidated to $0.50 mMO_2$/min.

• Journal of Periodontal and Implant Science
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• v.29 no.4
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• pp.785-804
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• 1999

The cell activities of bone metabolism is affected by growth factor rather than by hormone. The affects of growth factors on the bone activity were observed using various culture methods. Platelet-derived growth factor(PDGF) is produced from the well differentiated bone cell. It stimulates cell mitosis, synthesizes collagen in bone tissue and plays a role in healing response. The purpose of this study is to evaluate the effects that PDGF has on the activity and the proliferation of osteoblast by measuring the activity of alkaline phosphatase, the growth formation of calcified nodules, and osteocalcin production. In this study, HOS and ROS 17/2.8 osteoblastic cell line was used, along with variable concentrations of PDGF the were measured with osteoblastic proliferation. The cell proliferation of HOS and ROS 17/2.8 cells was stimulated dose- depentdently. Alakline phosphatase activity was significantly decreased by PDGF in osteoblastic cells. A number of small calcified nodules were observed in HOS cell treated with low concentrations(0.1, 0.4 ng/ml) of PDGF-BB and no significant difference from control group was found. High concentrations(10, 50 ng/ml) of PDGF suppressed calcified nodule formation. And osteocalcin production was inhibited with PDGF. These results suggest that PDGF stimulates the osteoblastic proliferation, whereas suppresses the individual cellular functions.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2003.11a
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• pp.322-327
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• 2003

It is important to know the accurate radionuclide inventory of radioactive waste for the reliable management. However, estimation of radionuclide concentrations in drummed radioactive waste is difficult and unreliable because of difficulties of direct detection, high cost, and radiation exposure of sampling personnel. In order to overcome these difficulties, scaling factors (SFs) have been used to assess the activities of radionuclides that could not be directly analyzed. A radionuclide assay system has been operated at KORI site since 1996 and consolidated scaling factor method has played a dominant role in determination of radionuclides concentrations. However, some problems are still remained such as uncertainty of estimated scaling factor values, inaccuracy of analyzed sample values, and disparity between the actual and ideal correlation pairs and the others. Therefore, it needs to improve the accuracy of scaling factor values. The scope of this paper is focused on the improvement of accuracy and representativeness of calculated scaling factor values based on statistical techniques. For the selection of reliable activity determination method, the accuracy of estimated SF values for each activity determination method is compared. From the comparison of each activity determination methods, it is recommended that SF determination method should be changed from the arithmetic mean to the geometrical mean for more reliable estimation of radionuclide activity. Arithmetic mean method and geometric mean method are compared based on the data set in KORI system.