• Journal of the Korean Society for information Management
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• v.38 no.3
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• pp.23-39
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• 2021

This study aims to explore research trends in Blockchain studies in South Korea using dynamic topic modeling and network analysis. To achieve this goal, we conducted the university & institute collaboration network analysis, the keyword co-occurrence network analysis, and times series topic analysis using dynamic topic modeling. Through the university & institute collaboration network analysis, we found major universities such as Soongsil University, Soonchunhyang University, Korea University, Korea Advanced Institute of Science and Technology (KAIST) and major institutes such as Ministry of National Defense, Korea Railroad Research Institute, Samil PricewaterhouseCoopers, Electronics and Telecommunications Research Institute that led collaborative research. Next, through the analysis of the keyword co-occurrence network, we found major research keywords including virtual assets (Cryptocurrency, Bitcoin, Ethereum, Virtual currency), blockchain technology (Distributed ledger, Distributed ledger technology), finance (Smart contract), and information security (Security, privacy, Personal information). Smart contracts showed the highest scores in all network centrality measures showing its importance in the field. Finally, through the time series topic analysis, we identified five major topics including blockchain technology, blockchain ecosystem, blockchain application 1 (trade, online voting, real estate), blockchain application 2 (food, tourism, distribution, media), and blockchain application 3 (economy, finance). Changes of topics were also investigated by exploring proportions of representative keywords for each topic. The study is the first of its kind to attempt to conduct university & institute collaboration networks analysis and dynamic topic modeling-based times series topic analysis for exploring research trends in Blockchain studies in South Korea. Our results can be used by government agencies, universities, and research institutes to develop effective strategies of promoting university & institutes collaboration and interdisciplinary research in the field.

• Journal of Global Scholars of Marketing Science
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• v.18 no.1
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• pp.59-80
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• 2008

Recently, e-sports are growing with potentiality as a new industry with conspicuous profit model. But studies that dealing with e-sports are not enough. Hence, proposes of this paper are both to establish basic model that is for the design of e-sport marketing strategy and to contribute toward future studies which are related to e-sports. Recently, the researches to explain sports-sponsorship through the identification theory have been discovered. Many researches say that somewhat proper identification is a requirement for most sponsors to improve the their images which is essential to sponsorship activity. Consequently, the research for sponsorship associated with identification in the e-sports, not in the physical sports is the core sector of this study. We extracted the variables from online's major characteristics and existing sport sponsorship researches. First, because e-sports mean the tournaments or leagues in the use of online game, the main event of the game is likely to call it online game. Online media's attributes are distinguished from those of offline. Especially, interactivity, anonymity, and expandibility as a e-sport game attributes are able to be mentioned. So, these inherent online attributes are examined on the relationship with flow. Second, in physical sports games, Fisher(1998) revealed that team similarity and team attractivity were positively related to team identification. Wann(1996) said that the result of former game influenced the evaluation of the next game, then in turn has an effect on the identification of team supporters. Considering these results in the e-sports side, e-sports gamer' attractivity, similarity, and match result seem to be important precedent variables of the identification with a gamer. So, these e-sport gamer attributes are examined on the relationship with both flow and identification with a gamer. Csikszentmihalyi(1988) defined the term flow as feeling status for him to be making current positive experience optimally. Hoffman and Novak(1996) also said that if a user experienced the flow he would visit a website without any reward. Therefore flow might be positively associated with user's identification with a gamer. And, Swanson(2003) disclosed that team identification influenced the positive results of sponsorship, which included attitude toward sponsors, sponsor patronage, and satisfaction with sponsors. That is, identification with a gamer expect to be connected with corporation identification significantly. According to the above, we can design the following research model. All variables used in this study(interactivity, anonymity, expandibility, attractivity, similarity, match result, flow, identification with a gamer, and identification with a sponsor) definitely were defined operationally underlying precedent researches. Sample collection was carried out to the person who has an experience to have enjoyed e-sports during June 2006. Much portion of samples is men because much more men than women enjoy e-sports in general. Two-step approach was used to test the hypotheses. First, confirmatory factor analysis was committed to guarantee the validity and reliability of variables. The results showed that all variables had not only intensive and discriminant validity, but also reliability. Then, research model was examined with fully structural equation using LISREL 8.3 version. The fitness of the suggested model mostly was at the acceptable level. Shortly speaking about the results, first of all, in e-sports game attributes, only interactivity which is called a basic feature in online situation affected flow positively. Secondly, in e-sports gamer's attributes, similarity with a gamer and match result influenced flow positively, but there was no significant effect in the relationship between the attractivity of a gamer and flow. And as expected, similarity had an effect on identification with a gamer significantly. But unexpectedly attractivity and match result did not influence identification with a gamer significantly. Just the same as the fact verified in the many precedent researches, flow greatly influenced identification with a gamer, and identification with a gamer continually had an influence on the identification with a sponsor significantly. There are some implications in these results. If the sponsor of e-sports supports the pro-game player who absolutely should have the superior ability to others and is similar to the user enjoying e-sports, many amateur gamers will feel much of the flow and identification with a pro-gamer, and then after all, feel the identification with a sponsor. Such identification with a sponsor leads people enjoying e-sports to have purchasing intention for products produced by the sponsor and to make a positive word-of-mouth for those products or the sponsor. For the future studies, we recommend a few ideas. Based on the results of this study, it is necessary to find new variables relating to the e-sports, which is not mentioned in this study. For this work to be possible, qualitative research seems to be needed to consider the inherent e-sport attributes. Finally, to generalize the results related to e-sports, a wide range of generations not a specific generation should be researched.

• The Korean Journal of Mycology
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• v.32 no.2
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• pp.79-88
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• 2004

Cordyceps pruinosa grows upon dead pupae of Lepidoptera and produces one or $3{\sim}4$ club-shaped stromata per host. The stromata have distinct club-shaped head and long stalk. The length of stromata varies from $1{\sim}3\;cm$. Apical head consists of densely crowded semi-immersed perithecia, which are $360{\sim}400\;{\times}\;180{\sim}200\;{\mu}m$ in size. Asci are $150\;{\mu}m$ in length and $2.8{\sim}3\;{\mu}m$ in diameter. Ascospores, which are $124{\sim}141\;{\mu}m$ in length, have thin thread-like structures in the middle with part-spores attached on both sides. Each ascospore does not separate into part-spores after dispersal, but each part-spore germinates and together develops a colony. The imperfect form produces phialides of $15{\sim}24\;{\times}\;2{\sim}3\;{\mu}m$ size, with spherical or spindle shaped conidia of $4{\sim}6\;{\times}\;1.8{\sim}2.4\;{\mu}m$ size, The anamorph was identified as Mariannaea elegans Samson. YMA and SDAY agar media with pH 7 was produced abundant mycelial growth with high density. Best mycelial growth was observed when dextrin was used as a carbon source. Lactose, saccharose and sucrose also produced high mycelial growth. Peptone, yeast extract and tryptone produced abundant mycelial growth, when used as nitrogen sources. Highest mycelial growth and density was observed when C/N ratio was 1 : 1 at the concentration of 12.5 g/l each. $KH_2PO_4$ was the best mineral source for mycelial growth. Highest mycelial dry wt. was produced in YM and SDAY broths. Optimum inoculum for 100 ml of liquid broth was 6 mycelial discs. Similarly, optimum liquid culture period was 7 days.

• Food Engineering Progress
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• v.21 no.2
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• pp.158-166
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• 2017

Although Semisulcospira libertina is generally regarded as a supplement for the alleviation of alcohol hangover, little is known about its effects on cell metabolism. Therefore, this study was conducted to analyze the constituents of the extracts prepared using different extraction methods and to compare their biochemical properties. The amino acid contents were found to be much higher in acidic and enzymatic hydrolysates than hot water extracts from S. libertina. DPPH radical scavenging activities in acidic and enzymatic hydrolysates were higher than those of hot water extracts. Three types of S. libertina hydrolysate was added to HepG2 cells damaged by acetaminophen (AAP), after which the survival rate of HepG2 cell were measured. In addition, lactate dehydrogenase (LDH) activities in the culture media were evaluated. The survival rates of HepG2 cells were $77.0{\pm}4.3%$ and $81.5{\pm}1.3%$ at 3 h and 5h enzymatic hydrolysates, respectively. These cell survival rates were higher compared to those of the negative control group ($67.8{\pm}4.3%$) treated only with acetaminophen. Cellular toxicities induced by treatment with AAP were also significantly alleviated in response to treatment with the extracts of S. libertina. In addition, the activities of 2 key enzymes that metabolize ethanol, alcohol dehydrogenase and aldehyde dehydrogenase, were upregulated by 4.7- and 2.7-fold respectively in response to treatment with a 3 h enzymatic hydrolysate of S. libertina. Taken together, these results provide biochemical evidence of the method by which S. libertina exerts its biological functions, including the alleviation of alcohol hangover and the protection of liver cells against toxic insults.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.12 no.1
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• pp.5-13
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• 2012

I-cell disease (mucolipidosis type II; MIM 252500) and pseudo-Hurler polydystrophy (mucolipidosis type III; MIM 252600) are disorders caused by abnormal lysosomal transport in cells. The presence of numerous inclusion bodies in the cytoplasm of fibroblasts, a lack of mucopolysacchariduria, increased lysosomal enzyme activity in serum, and decreased GlcNAc-phosphotransferase activity are hallmark. Here, we attempted to investigate phenotypical and biochemical characteristics of the knockoutmouse of GlcNAc-phosphotransferase ${\alpha}/{\beta}$ subunits; in addition, we also attempted to determine whether the lysosome enriched fraction derived from placenta can be beneficial to phenotype and biochemistry of the knockout mouse.We found that the knockout mouse failed to thrive and had low bone density, as is the case in human. In addition, skin fibroblasts from the animal had the same biochemical characteristics, including increased lysosomal enzyme activity in the culture media, in contrast to the relatively low enzyme activity within the cells. Intravenous injection of the lysosome rich fraction derived from placenta into the tail vein of the animal resulted in a gain of weight, while saline injected animals didn't.In conclusion, our study demonstrated the phenotypical and biochemical similarities of the knockout mouse to a mucolipidosis type II patient and showed the therapeutic potential of the lysosome enriched fraction. We admit that a larger scale animal study will be needed; however, the disease model and the therapeutic potential of the lysosome enriched fraction will highlight the hope for a novel treatment approach to mucopolipidosis type II, for which no therapeutic modality is available.

• Archives of design research
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• v.18 no.3 s.61
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• pp.129-138
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• 2005

It has been assumed that the clarification of a message is a necessary element for successful communication. However, in the today's complicated and changing environment of business marketing media, it is shown that the clarification of the message of advertisement may inhibit the effectiveness of communication. This study was to examine what was effective communication in advertisement when the company, provoking the people's negative emotional response, needs to establish new identities such as the goals and the special fields of business. In particular, the study was to investigate what effect the advertising strategy of strategically emitting ambiguous messages makes on the consumer's recognition, emotional attitude, reliability, and attitude towards the company. It was hypothesized that an ambiguous message in an advertisement has an effect on the consumer's recognition, emotional attitude, reliability, and attitude towards the company. Three texts from the 'Imagination Praises' campaign of KT&G which has been in process since 2003 were systematically sampled and the survey was performed by the means of questionnaires made on the sample The results showed that the ambiguous message of advertising texts gained better responses on the consumer's attention, good impression, affirmation, memory, sympathy than the dear message and that the ambiguous message had an effect on the consumer's attitude towards the advertisement itself. Thus, it could be tentatively concluded that the ambiguous message could be more effective in recognition and recall to promote the changes of identities of the company having the people's unfavorable emotion. But there wasn't any evidence that an ambiguous message in an advertisement was more effective in terms of the consumer's emotional response, reliability, and attitude towards the company. From this, it could be inferred that the receiver had an uncomfortable, doubtful and negative attitude about the implicit expressive code contained in the message. In the future deeper qualitative studies can compensate for the limited explanation of this empirical study focused on statistical analyses.

• Food Science and Preservation
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• v.31 no.1
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• pp.149-160
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• 2024

Dextran is a glucose homo-polysaccharide with a predominantly α-1,6 glycosidic linkage of microbial source and is known to be produced primarily by lactic acid bacteria. However, it can also be obtained through the dextran dextrinase of acetic acid bacteria (Gluconobacter oxydans). The dextrin-based dextran was obtained from rice starch using G. oxydans fermentation of rice hydrolysate, and its properties were studied. Both dextrin- and rice hydrolysate-added media maintained the OD value of 6 after 20 h of incubation with acetic acid bacteria, and the gel permeation chromatography (GPC) analysis of the supernatant after 72 h of incubation confirmed that a polymeric material with DP of 480 and 405, which was different from the composition of the substrate in the medium, was produced. The glucose linkage pattern of the polysaccharide was confirmed using the proton nuclear magnetic resonance (¹H-NMR) and the increased α-1,4:α-1,6 bond ratio from 0.23 and 0.13 to 1:2.37 and 1:4.4, respectively, indicating that the main bonds were converted to α-1,6 bonds. The treatment of dextrin with a rat-derived alpha-glucosidase digestive enzyme resulted in a slow release of glucose, suggesting that rice hydrolysate can be converted to dextran using acetic acid bacteria with glycosyltransferase activity to produce high-value bio-materials with slowly digestible properties.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 1998.10a
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• pp.83-106
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• 1998

This study was conducted to investigate the probiotics(acid and bile resistance, fermentation properties, viability, cholesterol assimilation, antimicrobial activity, antimutagenicity, and immunoactivation) of the strains of bifidobacteria isolated from healthy Koreans and to investigate the effects of oral administration of Bifidobacterium longum A-2 on the fecal microflora, ${\beta}-glucuronidase$ activity, pH values, Ammonia concentration. The experimental results are summarized as follows: The probiotics were tested for 23 strains including three commer챠al strains as controls. Compared to other strains, strains of A-2 and A-9 showed more acid resistance whereas A-2, A-5, A-13, A-14, A-18 and A-22 showed excellent bile resistances. The properties of bifidobacteria during fermentation were tested. Strains of A-1, A-2, A-3, A-4, A-6, and A-23 resulted in less than pH 4.5 and titratable acidity over 0.90 after 24 hr of fermentation. When the strains of A-2 was grown with glucose, maltose, and fructooligosaccharide, the acetic acid production were higher than with sorbitol and mannitol. The storage stability of the strains of A-2 and A-22 were tesed, indicating the strain A-2 was more stable over 10 days of storage at both $4^{\circ}C$ and $20^{\circ}C$ than A-22. The strains of A-8, A-10, A-11, A-12 and A-20 assimilated more than 30% of cholesterol included in the media. The strains of A-1 and A-2 showed antimicrobial activity against Sta. aureus. The antimutagenicity of the strains were also tested, showing that the mutation was suppressed more by three strains(A-2, A-12, and A-23). In addition, strain A-5 improved immunological activity(phagocytosis, $TNF-{\alpha}$, IL-6) more than other strains. In the effects of oral administration of Bif. longum A-2, the number of fecal bifidobacteria was siginificantly increased(p<0.01) and the level of fecal ${\beta}-glucuronidase$ also was siginificantly reduced(p<0.05). However there were no siginificant differences in the level of Lαctobacilli, Enterobacteriaceae, Clostridium perfringens, pH and ammonia by the administration. The results suggested that Bif. longum A-2 may be met the criteria for probiotics culture.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.43 no.2 s.308
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• pp.19-29
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• 2006

As the security of personal information is becoming more important in mobile phones, we are starting to apply iris recognition technology to these devices. In conventional iris recognition, magnified iris images are required. For that, it has been necessary to use large magnified zoom & focus lens camera to capture images, but due to the requirement about low size and cost of mobile phones, the zoom & focus lens are difficult to be used. However, with rapid developments and multimedia convergence trends in mobile phones, more and more companies have built mega-pixel cameras into their mobile phones. These devices make it possible to capture a magnified iris image without zoom & focus lens. Although facial images are captured far away from the user using a mega-pixel camera, the captured iris region possesses sufficient pixel information for iris recognition. However, in this case, the eye region should be detected for accurate iris recognition in facial images. So, we propose a new fast iris detection method, which is appropriate for mobile phones based on corneal specular reflection. To detect specular reflection robustly, we propose the theoretical background of estimating the size and brightness of specular reflection based on eye, camera and illuminator models. In addition, we use the successive On/Off scheme of the illuminator to detect the optical/motion blurring and sunlight effect on input image. Experimental results show that total processing time(detecting iris region) is on average 65ms on a Samsung SCH-S2300 (with 150MHz ARM 9 CPU) mobile phone. The rate of correct iris detection is 99% (about indoor images) and 98.5% (about outdoor images).

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.12 no.3
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• pp.65-74
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• 2017

There have been questions how entrepreneurs think, act and why individuals become entrepreneurs. The trait-based explanation of entrepreneurial activities has been main stream. However, the trait-based theory has been criticized because it assumes that entrepreneurial traits are inherited, stable and enduring over time. This research accepts the cognitive theory to see how entrepreneurs learn or accept others' values, how entrepreneurial perceptions of opportunity impact entrepreneurial actions and how individuals acquire the social legitimation of the formation of entrepreneurial activities. In order to capture the attitudes, activities and motivations of people who are involved in entrepreneurial activities, the author uses the GEM Korea 2016 data. The data from the Global Entrepreneurship Monitor(GEM) has been well known for the data to capture individuals early-stage entrepreneurial activities. This paper used the sample from the APS(Adult Population Survey) of the GEM which was completed by a representative sample of two thousand adults in Korea by the qualified survey vendor, with strict procedures and oversight by the GEM central data team. The hypotheses are tested with logit regression analysis to estimate the probability of the influence of perceptual variables such as individual perception in social learning, the opportunity recognition in the environment, and social legitimation in the entrepreneurial activities. Based on the results, individuals tend to have high entrepreneurial activities if individuals have high self-efficacy. Also, the existence of role models around the entrepreneurs encourages the individuals involve in entrepreneurial activities more however the perception of opportunity in the environment is not strongly associated with entrepreneurial activities. The media exposure of successful entrepreneurs is more important than others' perception of entrepreneurs on the desirable career option or respect from communities. This paper can contribute to the cognitive processes, particular perception about oneself, as well as perception which is impacted by a community or a society.