• Microbiology and Biotechnology Letters
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• v.46 no.1
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• pp.29-39
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• 2018

Vibrio vulnificus needs various responsive mechanisms to survive and transmit successfully in alternative niches of human and marine environments, and to ensure the acquisition of steady energy supply to facilitate such unique life style. The bacterium had genetic constitution very different from that of Escherichia coli regarding metabolism of glycogen, a major energy reserve. V. vulnificus accumulated more glycogen than other bacteria and at various levels according to culture medium and carbon source supplied in excess. Glycogen was accumulated to the highest level in Luria-Bertani (3.08 mg/mg protein) and heart infusion (4.30 mg/mg protein) complex media supplemented with 1% (w/v) maltodextrin at 3 h into the stationary phase. Regarding effect of carbon source, more glycogen was accumulated when maltodextrin (2.34 mg/mg protein) was added than when glucose or maltose (0.78.1-14 mg/mg protein) was added as an excessive carbon source to M9 minimal medium, suggesting that maltodextrin metabolism might affect glycogen metabolism very closely. These results were supported by the analysis using the malP (encoding a maltodextrin phosphorylase) and malQ (encoding a 4-${\alpha}$-glucanotransferase) mutants, which accumulated much less glycogen than wild type when either glucose or maltodextrin was supplied as an excessive carbon source, but at different levels (3.1-80.3% of wild type glycogen). Therefore, multiple pathways for glycogen metabolism were likely to function in V. vulnificus and that responding to maltodextrin might be more efficient in synthesizing glycogen. All of the glycogen samples from 3 V. vulnificus strains under various conditions showed a narrow side chain length distribution with short chains (G4-G6) as major ones. Not only the comparatively large accumulation volume but also the structure of glycogen in V. vulnificus, compared to other bacteria, may explain durability of the bacterium in external environment.

• Journal of Korean Library and Information Science Society
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• v.43 no.1
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• pp.123-141
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• 2012

The purpose of this study is to examine the possibility of using the WorldCat, an International Union Catalog operated by OCLC as a tool for analyzing the trend of knowledge distribution in libraries around the world. In this study, four subject keywords, that is, Korea, Korean, Japan, and Japanese, were used to search materials related to Korea and Japan, and four facets, including medium, genre, language, and user level, were used to categorize search results from the WorldCat. The result shows that information resources related to Korea held by libraries around the world are only a little more than a third of Japan-related information resources. Especially Korea-related information resources for juveniles are less in numbers and lack in diversity in languages, media and genres, when compared with Japan-related information resources. Also an examination of two bibliographic records demonstrates that viewpoints expressed in user contributed reviews might affect diffusion of knowledge on certain subjects in the Next Generation Library Catalog.

• Journal of KIISE:Information Networking
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• v.36 no.6
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• pp.471-480
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• 2009

One of the principal impediments to the achievement of a scalable access control for a large number of subscribers in a public broadcast is to distribute key update messages reliably to all stateless receivers. However, in a public broadcast, the rekeying messages can be dropped or compromised during the transmission over an insecure broadcast channel, or transmitted to the receivers while it was off-line. In this study, we propose a novel group key management scheme that features a mechanism that allows the legitimate receivers to recover the current group key even if they lose key update messages for long-term sessions using short hint messages and member computation. The performance analysis result shows that the proposed scheme has advantages of the scalable and efficient rekeying compared with the previous reliable group key distribution schemes. The proposed key management scheme targets a conditional access system in a media broadcast where there is no feedback channel from receivers to the broadcasting station.

• The Journal of Industrial Distribution & Business
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• v.9 no.5
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• pp.47-62
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• 2018

Purpose - Based on preceding studies, this thesis focuses on the finding of the definition and category of mobile tourism application and deriving out its characteristics. And after looking for how they make influences on continuous intention to use, we make empirical study with TAM model. Research design, data, and methodology - There are many Chinese tourist who visit Korea with user's constant intention to use of tourism application. This study is to find out the definition and category of mobile tourism application through research of preceding study and to fomulate the research model and hypothesis that how tourism application attributes (convenience, interaction, accessibility, local basis, security) affect constant intention to use of mobile tourism application. In order to verify a hypothesis, we conducted a survey for Chinese users of tourism application. In empirical study, we analyzed a structure model for frequency analysis, reliability analysis, exploratory factor analysis, validity analysis through IBM SPSS Statistics 21.0 and IBM SPSS AMOS 21.0 Results - Among tourism applications, convenience, interaction, accessibility and local basis have positive effects on both perceived usefulness and perceived easiness respectively. But security does not. Also perceived easiness has a positive effect on perceived usefulness. Finally, perceived usefulness and perceived easiness have positive effect on constant intent to use. Conclusions - Tourism application enterprises should put emphasis on design such as menu or function in order to simplify the operation of new services for new customers. Therefore, comfortable user interface and development of useful function can improve tourism application. Consequently, it leads to the promotion of tourism application. Also, when users perceive tourism application as a useful media which is easy, comfortable and useful content, the degree of constant intention to use becomes increased. It is important to provide plentiful and useful contents for customers and to develop user interface such as easy operation because these factors have positive effects on constant demand and use of tourism application.

• Journal of Environmental Science International
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• v.21 no.12
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• pp.1455-1462
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• 2012

The vertical distributions of nitrifying bacteria in aerobic fixed biofilm were investigated to evaluate the relationship between nitrification performance and microbial community at different HRT. Fluorescent in situ hybridization (FISH) and portable ion selective microelectrode system were adopted to analyze microbial communities and ions profiles according to the biofilm depth. Cilia media packed MLE (Modified Ludzack-Ettinger) like reactor composed of anoxic, aerobic I/II was operated with synthetic wastewater having COD 200 mg/L and $NH_4{^+}$-N mg/L at HRT of 6 hrs and 4 hrs. Total biofilm thickness of aerobic I, II reactor at 4 hrs condition was over two times than that of 6 hrs condition due to the sufficient substrate supply at 4 hrs condition (6 hrs; aerobic I 380 ${\mu}m$ and II 400 ${\mu}m$, 4 hrs; aerobic I 830 ${\mu}m$ and II 1040 ${\mu}m$). As deepen the biofilm detection point, the ratio of ammonia oxidizing bacteria (AOB) was decreased while the ratio of nitrite oxidizing bacteria (NOB) was maintained similar distribution at both HRT condition. The ratio of AOB was higher at 4 hrs than 6 hrs condition and $NH_4{^+}$-N removal efficiency was also higher at 4 hrs with 89.2% than 65.4% of 6 hrs. However, the ratio of NOB was decreased when HRT was reduced from 6 hrs to 4 hrs and $NO_2{^-}$-N accumulation was observed at 4 hrs condition. Therefore, it is considered that insufficient HRT condition could supply sufficient substrate and enrichment of AOB in all depth of fixed biofilm but cause decrease of NOB and nitrite accumulation.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.15
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• pp.6299-6302
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• 2015

Background: The rise in consumption of tobacco products among youth is a public health concern in India. Several studies have shown that advertisements promoting tobacco products influence decisions and behaviour of youth towards smoking. Objective: To ascertain which method of Tobacco Advertising, Promotion and Sponsorship (TAPS) was more influential for initiating tobacco use in youth in India. Materials and Methods: The secondary data of youth (15-24 years) from nationally representative Global Adult Tobacco Survey (GATS) conducted in 2009-2010 was analyzed. Odds ratio and p-value were used to know the association between TAPS and initiation of use of tobacco products among youth. Logistic regression was used to determine the most significant means of TAPS altering the youth's behaviour towards tobacco products. Results: Out of 13,383 youths, 1,982 (14.7%) used smokeless forms of tobacco and 860 (6.38%) used smoke forms. Logistic regression reveals that promotional activities mainly through cinemas (p<0.05) and providing free samples of tobacco products (p < = .001) were most influential means of initiating consumption of tobacco products among youth. Conclusions: The smoking in youth is associated with watching advertisements particularly in cinema and promotional activities like distribution of free samples, coupons and sales on the price of tobacco products. Stronger legislative measures should be enforced to curb promotional advertisements in cinemas and distribution of free samples.

• Journal of Digital Convergence
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• v.13 no.4
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• pp.219-225
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• 2015

There has been an exponential growth in the distribution and possession of sensitive information because of the emergence of various information channels such as smart devices, social media, etc. This enables the internet based web or mobile service operation institutions collecting the more personal information with ease, and in turn causes the issues of the privacy concerns. Followings are the results of this study: First, the information privacy concern has the negative effects upon the trust. Second, the information privacy concern has the negative effects upon the provision intention of personal information and the trust has positive effects upon the offering intention of personal information. At last, the offering intention of the personal information has the positive effects upon the behavior to provide the personal information.

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.1
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• pp.99-102
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• 2005

Organic solvents are widely used in biotransformation systems. There are many efforts to reduce the consumption of organic solvents because of their toxicity to the environment and human health. In recent years, several groups have started to explore novel organic solvents called room temperature ionic liquids in order to substitute conventional organic solvents. In this work, lipase-catalyzed transesterification in several uni- and bi-phasic systems was studied. Two representative hydrophobic ionic liquids based on 1-butyl-3-methylimidazolum coupled with hexafluorophosphate ([BMIM][$PF_6$]) and bis[{trifluoromethylsulfonyl} imide] ([BMIM] [$Tf_{2}N$]) were employed as reaction media for the transesterification of n-butanol. The commercial lipase, Novozym 435, was used for the transesterification reaction with vinyl acetate as an acyl donor. The conversion yield was increased around $10\%$ in a water/[BMIM][$Tf_{2}N$] bi-phasic system compared with that in a water/hexane system. A higher distribution of substrates into the water phase is believed to enhance the conversion yield in a water/[BMIM][$Tf_{2}N$] system. Partition coefficients of the substrates in the water/[BMIM][$Tf_{2}N$] bi-phasic system were higher than three times that found in the water/hexane system, while n-butyl acetate showed a similar distribution in both systems. Thus, RTILs appear to be a promising substitute of organic solvents in some biotransformation systems.

• Journal of Broadcast Engineering
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• v.25 no.1
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• pp.36-47
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• 2020

The improved belief-propagation-based algorithms, such as normalized min-sum algorithm (NMSA) or offset min-sum algorithm (OMSA), are widely used to decode LDPC(Low-Density Parity-Check) codes because they are less computationally complex and work well even at low SNR(Signal-to-Noise Ratio). However, these algorithms work well only when an appropriate normalization factor or offset value is used. A new method that uses a CMD(Check Node Message Distribution) chart and least-square method, which has been recently proposed, has advantages on computational complexity over other approaches to get optimal coefficients. Furthermore, this method can be used to derive coefficients for each iteration. In this paper, we apply this method and propose an algorithm to derive a combination of normalization factor and offset value for a combined normalized and offset min-sum algorithm to further improve the decoding of LDPC codes. Simulations on the next-generation broadcasting standards, ATSC 3.0 LDPC codes, prove that a combined normalized and offset min-sum algorithm which takes the proposed coefficients as correction coefficients shows the best BER performance among other decoding algorithms.

• Journal of Korean Society on Water Environment
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• v.20 no.6
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• pp.670-675
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• 2004

Humic acids are macromolecules originated from natural water, soil, and sediment. The characteristics of humic acid enable it to change the distribution of metals as well as many kinds of organic contaminants and to determine the sorption of them from soil solution. To see the effect of humic acid on the removal rate of organic contaminants and heavy metals, batch-scale experiments were performed. As a natural geosorbent, black shale was used as a sorbent media, which showed hight sorption capacity of trichloroethylene (TCE), lead, cadmium and chromium. The effect of sorption-desorption, pH, ionic strength and the concentration of humic acid was taken into consideration. TCE sorption capacity by black shale was compared to natural bentonite and hexadecyltrimethylammonium (HDTMA) modified bentonite. The removal rate was good and humic acid also sorbed onto black shale very well. The organic part of humic acid could effectively enhance the partition of TCE and it act as an electron donor to reduce Cr(VI) to Cr(III). Cationic metal of Pb(II) and Cd(II) also removed from the water by black shale. With 3 mg/L of humic acid, both Pb(II) and Cd(II) were removed more than without humic acid. That could be explained by sorption and complexation with humic acid and that was possible when humic acid could change the hydrophobicity and solubility of heavy metals. Humic acid exhibited desorption-resistivity with black shale, which implied that black shale could be an alternative sorbent or material for remediation of organic contaminants and heavy metals.