• The Journal of Korean Institute of Communications and Information Sciences
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• v.42 no.5
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• pp.1009-1019
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• 2017

Mobile Edge Computing(MEC) is a emerging technology to cope with mobile traffic explosion and to provide a variety of services having specific requirements by means of running some functions at mobile edge nodes directly. For instance, caching function can be executed in order to offload mobile traffics, and safety services using real time video analytics can be delivered to users. So far, a myriad of methods and architectures for personalized service recommendation have been proposed, but there is no study on the subject which takes unique characteristics of mobile edge computing into account. To provide personalized services, acquiring users' context is of great significance. If the conventional personalized service model, which is server-side oriented, is applied to the mobile edge computing scheme, it may cause context isolation and privacy issues more severely. There are some advantages at mobile edge node with respect to context acquisition. Another notable characteristic at MEC scheme is that interaction between users and applications is very dynamic due to temporal relation. This paper proposes the local service recommendation platform architecture which encompasses these characteristics, and also discusses the personalized service recommendation mechanism to be able to mitigate context isolation problem and privacy issues.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.6
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• pp.852-858
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• 1998

We have isolated a bacterial strain that tends to kill P. micans from the mixed culture of p. minns plus seawater filtrate (poresize, 0.8 $\mu$m) collected at Masan bay in July 1996, in which the mixed culture grown in the f/2 medium. According to the experimental results of the isolated bacterium such as fatty acids analysis, morphological and biochemical characteristic tests, the strain was supposed to be a Pseudomonas and then it was named as Pseudomonas sp. LG-2. The killing effect of Pseudomonas sp. LG-2 against P. micans was proportionally increased with the concentrations of culture filtrate (pore size, 0.8 $\mu$m) is well as with the number of bacterium inoculated. In the mixed culture inoculated with $1.3\times10^6$ cells/ml of Pseudomonas sp. LG-2, the number of P. micans (2,000 cells/ml) was gradually decreased and then killed below 100 cells/ml within 7 days. In addition, the culture filtrate with $30\%$ of final concentration revealed a significant killing effect against P. micans around 3 days after culture. In the relationship between killing effects and growth stage of Pseudomonas sp. LG-2, the culture filtrate at lag phase has little effects on P. micans. In constant, the culture filtrate at mid-log phase showed the killing effect by decreasing P. micans to 112 in number within 5 days. In particular, the culture filtrate at stationary phase showed a significant killing effect against P. micans in which the majority of it was killed after 3 day culture. The species specificity of killing effects of Pseudomonas sp. LG-2 against 5 species of dinoflagellate was only found in P. micans and Scrippsiella trochoidea.

• Plant Biotechnology Reports
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• v.5 no.4
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• pp.331-344
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• 2011

The well-conserved NBS domain of resistance (R) genes cloned from many plants allows the use of a PCR-based approach to isolate resistance gene analogs (RGAs). In this study, we isolated an RGA (CapRGC) from Capsicum annuum "CM334" using a PCR-based approach. This sequence encodes a protein with very high similarity to Rx genes, the Potato Virus X (PVX) R genes from potato. An evolutionary analysis of the CapRGC gene and its homologs retrieved by an extensive search of a Solanaceae database provided evidence that Rx-like genes (eight ESTs or genes that show very high similarity to Rx) appear to have diverged from R1 [an NBS-LRR R gene against late blight (Phytophthora infestans) from potato]-like genes. Structural comparison of the NBS domains of all the homologs in Solanaceae revealed that one novel motif, 14, is specific to the Rx-like genes, and also indicated that several other novel motifs are characteristic of the R1-like genes. Our results suggest that Rx-like genes are ancient but conserved. Furthermore, the novel conserved motifs can provide a basis for biochemical structural. function analysis and be used for degenerate primer design for the isolation of Rx-like sequences in other plant species. Comparative mapping study revealed that the position of CapRGC is syntenic to the locations of Rx and its homolog genes in the potato and tomato, but cosegregation analysis showed that CapRGC may not be the R gene against PVX in pepper. Our results confirm previous observations that the specificity of R genes is not conserved, while the structure and function of R genes are conserved. It appears that CapRGC may function as a resistance gene to another pathogen, such as the nematode to which the structure of CapRGC is most similar.

• Journal of Advanced Navigation Technology
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• v.21 no.4
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• pp.377-385
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• 2017

The solar cell need the characteristic interpreting because the solar cell changes greatly according to the isolation, temperature and load in the photovoltaic development. Moreover, to get many energy in photovoltaic development need the position tracking of the sun according to the environment change. Also, The solar cells should be operated at the maximum power point. In this paper, I used microprocessor and sensor and designed to improve the efficiency of the photovoltaic system the photovoltaic position tracker device, and compared the normal photovoltaic system of fixed form with the photovoltaic system of solar position tracked form. Moreover, compared the catalogue of solar cell module and the simulation through a mathematics modelling with the solar cell's characteristic interpreting and composed an power conversion system with boost converter and voltage source inverter. Used the constant voltage control method for maximum power point tracking in boost converter control and, used the SPWM(Sinusoidal Pulse Width Modulation) control method in inverter control. The result was less then 5% when compared the catalogue of solar cell module and the simulation through a mathematics modelling. The boost rate of boost converter was similar to 167 % with the simulation.

• Korean Journal of Culture and Social Issue
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• v.14 no.2
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• pp.63-81
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• 2008

Hasteful behavior means choosing the best suited methods while behaving fast and quickly. We can't conclude whether hasteful behavior is totally bad or good. Striving for achievement of own certain purpose reflects achievement motivation or need for achievement. However, this striving also has potentiality of missing confirmation, therefore the potentiality may cause errors. The aim of this study is to investigate the psychological structure and characteristic of the hasteful behavior. One hundred ninety-one students conducted Hasteful Behavior Questionnaire, Achievement Motivation Measuring Scale, and NEO Personality Inventory. We analyzed data of 188 respondents, because of missing value. The result of factor analysis showed that hasteful behavior consisted of 5 factors- 「Uncomfortableness」, 「Time Pressure」, 「Isolation」, 「Boring Condition」, and 「Expecting Rewards」. According to correlations among the hasteful behavior factors and the relationship between hasteful behavior and achievement motivation, we found that hasteful behavior had two aspects, one was "Missing Confirmation(MC)" and the other was "Need for Achievement(NA)". We also found that 「Time Pressure」 was related to the both aspects. MC had a positive relation to Neuroticism, whereas MC correlated negatively with Conscientiousness. On the other hand, NA had a positive relationship with Extraversion and Achievement Striving.

• Journal of the Korean Chemical Society
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• v.19 no.5
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• pp.325-330
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• 1975

Complex formation between ferric ion and phosphoric acid has been studied in the wide range of the acid concentration(0${\sim}40{\%}$) by uv-visible spectroscopy and by characterization of the isolated products. The electronic spectra of Fe(III)-containing phosphoric acid solutions exhibit two visible bands at 19.2 and 24.1 kK, which are characteristic of Fe(III)-phosphate complex formation. The measurements of acid concentration dependence of the opical density of the 24.1 kK band indicates the presence of two distinct forms of Fe(Ⅲ)-phosphate complexes possibly $[Fe(H_xPO_4)]^{x+}\;and\;[Fe_2 (H_xPO_4)]^{(3+x)+}$. The 1:1 complex has been isolated for characterization, and the phosphate ion was found to be coordinated to the metal in monobasic state whereas the isolation of the dimeric species was unsuccessful.

• Korean Journal of Microbiology
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• v.49 no.4
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• pp.419-423
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• 2013

Three genes, nsdD, nsdC, and veA are known to be necessary for positive regulating sexual development of Aspergillus nidulans. Since the mutants of those genes hardly form fruiting bodies in heterokaryons constructed by cross between two of them, it is difficult to isolate double mutants. In this work, double mutants of ${\Delta}nsdD$ ${\Delta}veA$ and ${\Delta}nsdD$ ${\Delta}nsdC$ were isolated using the characteristic of the nsdD deletion mutant that it could develop mature cleistothecia in hypoxic and low temperature culture condition. According to the phenotypes of double mutants, the nsdD gene controls the apical growth independently with veA or nsdC. Deletion of veA or nsdC was epistatic to nsdD deletion for pigment production. Conidia formation in submerged culture with lactose as sole carbon source was observed in ${\Delta}nsdD$ ${\Delta}nsdC$ double mutant implicating it to be unique phenotype of nsdC deletion.

• Journal of Life Science
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• v.16 no.2 s.75
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• pp.282-288
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• 2006

Activity-guided fractionations led to the isolation of antitumor compound, ergosterol peroxide ($5{\alpha},\;8{\alpha}-epideoxy-24(R)-methylcholesta-6,\;22-dien-3{\beta}-ol$) from the fruiting body of Pleuratus eryngii that was cultivated artificially. This sterol structure was established by using spectroscopic methods ($^1H\;and\;^{13}C$ nuclear magnetic resonance and high resolution mass spectra). The purified compound showed a molecular formular of $C_{28}H_{44}O_3$ displaying characteristic features of epidioxy sterols. The 50% inhibitory concentrations ($IC_{50}$) of ergosterol peroxide against human lung cancer cell line (A549) and human ovarian cell line (SK-OV3) were $7{\mu}M\;and\;14{\mu}M$, respectively. In the DNA fragmentation assay, the compound showed the programmed cell death causing the chromosomal DNA fragmentation. It reveals that ergosterol peroxide arrests G1 phase of the cell division cycle.

• Korean Journal of Food Science and Technology
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• v.23 no.4
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• pp.414-419
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• 1991

Polyphenol oxidase from Jerusalem artichoke(Helianthus tuberosus L.) tubers was partially purified by precipitation with ammonium sulfate, followed by gel filtration on Sephadex G-100. The enzyme showed maximal activity at pH 6.5 and $4^{\circ}C$. Kinetic studies indicated $K_{m}$ value of 3 mM for catechol and activation energy of 72.6 kcal/mole. As for substrate specificity of polyphenol oxidase the enzyme showed high affinity towards diphenol compounds, but not towards monophenols. The enzamatic browning was completely inhibited at 1 mM concentration of L-ascorbic acid, sodium hydrosulfite and L-cystein(HCl). The activity of polyphenol oxidase in 0.1 M potassium phosphate buffer(pH 6.5) was fairly stable for a week at $4^{\circ}C$, while it decreased remarkably at $25^{\circ}C$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.3
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• pp.571-575
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• 2004

Escherichia coli O157:H7 cause hemorrhagic colitis and the extraintestinal complication of hemolytic-uremic syndrome, with their higher incidence occurring in children. Lipopolysaccharide (LPS) of E. coli O157:H7 is very important to make IgG anti-LPS with bactericidal activity. To identify the characteristic of E. coli OI57:H7, we isolated 60 MDa plasmid and amplified stx genes of shiga-like toxin (Stx) 1, 2 of E. coli O157:H7 by polymerase chain reaction (PCR) method. Using the simple purification method which contained phenol extract, ethanol precipitation and gel filtration steps, the LPS of E. coli O157:H7 was isolated and purified. Finally, we confirmed the purity of LPS through SDS-PAGE and silver nitrate staining.