• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2006.05a
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• pp.555-558
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• 2006

Bluetooth is an open specification technology for short-range wireless connectivity between electronic devices. This paper analyzes the effects of interference on the performance of a Bluetooth system. Two performance criteria used in the study are the signal to interference power ratio (SIR) and the bit error rate (BER) of the bits received. The interference from various sources on the performance of a Bluetooth device is analyzed, and these quantities are plotted against Eb/No and SIR for various channel conditions in figures.

• Journal of the Korean Chemical Society
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• v.54 no.1
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• pp.65-70
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• 2010

We describe the immune stimulatory effects of compounds determined by means of activity-monitored extraction and isolation techniques. As a result, 4-carboethoxy-6-methoxy-2-quinolone (1) and 4-carboethoxy-6-hydroxy-2-quinolone (2) were isolated from the ethyl acetate-soluble fraction of the Oryza sativa cv. Heugnambyeo bran, and were determined to exert significant inhibitory effects in macrophage cell line (murine RAW 264.7) and murine splenocytes. The structures were elucidated on the basis of spectroscopic evidence, particularly the results obtained via hetero nuclear multiple-bond connectivity and high-resolution MS spectroscopy. Up to date, compound (1) was isolated as natural sources for the first time.

• The Research Journal of the Costume Culture
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• v.23 no.2
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• pp.228-241
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• 2015

The purpose of this study was to verify the effect of mobile fashion shopping characteristics and perceived interactivity on perceived usefulness, and the effect of perceived usefulness on purchase attitude and purchase intention based on TAM (Technology Acceptance Model). We conducted the survey targeting smartphone users in their 20s~30s living in Seoul and metropolitan area. Among 483 data collected, we used 452 samples except 31 unreliable respondents for the analysis. To analyze the structural equation model, we did factor analysis, reliability analysis, and structural equation model analysis using SPSS 18.0 and AMOS 16.0. The results were as follows: We confirmed 5 mobile fashion shopping characteristics (enjoyment, credibility, instant connectivity, security, and personalization) and 3 perceived interactivity factors (control, responsiveness and two-way communication, and contextual offer) as results of confirmative factor analysis. Mobile fashion shopping characteristics and perceived interactivity had positive effects on perceived usefulness. Mobile fashion shopping characteristics affected perceived interactivity and also had indirect effect on perceived usefulness via perceived interactivity. In other words, mobile fashion shopping characteristics had direct and indirect effect on perceived usefulness. Perceived usefulness influenced purchase attitude and purchase attitude influenced purchase intention. Perceived usefulness had direct effect on purchase intention and the indirect effect through purchase attitude was significant.

• SUVANNABHUMI
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• v.15 no.2
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• pp.23-55
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• 2023

Just as globalization has many aspects and has developed in various, sometimes contradictory ways with both positive and negative impacts, so too would the reverse process of deglobalization have wide-ranging effects for individuals, communities, and nations. Some parts of globalization began to fray during the coronavirus pandemic (e.g. failing supply chains and disarray in the global shipping industry). Deglobalization would bring about much more significant changes in focusing on local production and consumption, eschewing non-essential flights and international tourism, and replacing personal experience with virtual presence. These impacts would be particularly severe for Vietnam, since its government has placed intensive connectivity with global production at the center of its model for the rapid development on which much of its legitimacy rests and it has joined as many international, multilateral organizations, and protocols as it has been able to do. Through critical analysis of secondary data from a wide range of sources, this paper examines the motivations that people, institutions, and governments might have to pursue deglobalization and then seeks evidence for whether the changes that would bring have started to affect Vietnam. While it is difficult to be too certain about this while the pandemic continues, it is evident that pressures are building in the global north to reconfigure supply chains for greater security, to reduce carbon emissions through regulating long-distance exchanges, and to withdraw from personal contacts. It is argued that a focus on digitalization in economy and society will help to mitigate the negative effects of deglobalization on Vietnam, at least in the medium-term.

• The Journal of Information Systems
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• v.24 no.4
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• pp.21-42
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• 2015

Purpose The high-technology market shows characteristics of a highly interdependent network market in both supply-side and demand-side, compared to other markets. Particularly, for convergence products, connectivity with related elements, as well as characteristics of innovation itself, is relatively important to the extent that they combine functions provided by several devices into a single device. Therefore, this study aims to identify whether network externality exists in value and adoption of a convergence product and discover a source of network externality, if any. Design/methodology/approach: Through a preceding research analysis and a literature review, 'social influence' and 'network size' have been drawn as direct network elements. On the other hand, general (comprehensive) concept compatibilities including 'intra-technology compatibility', 'inter-technology compatibility' and 'complementary-technology compatibility' are regarded as indirect network elements. Findings: Major findings are as followed;- First, it is shown that the factors influencing on perceived value of a convergence products are 'social influence' and 'network size' as the direct network elements and 'complementary-compatibility' among indirect network elements. Second, it is also found that 'intra-technology compatibility', 'inter-technology compatibility', 'complementary-compatibility' and 'perceived value' have significant effects on adoption of a convergence product. Particularly, it is known that 'complementary-compatibility' is an important source of network externality as it plays a decisive role in value judgment and has significant effects on perceived value. It is worthwhile to notice that this study comprehensively explains effects of network on high-tech products by structuring comparability as a multi-dimensional concept, as well as direct network elements.

• The Journal of the Korea Contents Association
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• v.15 no.12
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• pp.517-524
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• 2015

In this paper we investigate the factors influencing the intention-to-use of Alibaba mobile payment in China. Our research model includes the mobile payment service factors ('instant connectivity', 'security', and 'use convenience'), the user's individual factors ('preferential' and 'individual characteristics'), 'satisfaction', and 'intention to use'. We surveys the current and potential mobile payment service users in China and analyzes with Structural Equation Model. The results show that all the mobile payment service factors give positive effects to 'satisfaction'. The 'individual characteristics', one of the user's individual factors, also gives positive effects to 'satisfaction', however, 'preferential' does not give positive effects. In addition, 'satisfaction' is found to give positive effects to 'intention to use'.

• Journal of Microbiology and Biotechnology
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• v.33 no.8
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• pp.1013-1022
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• 2023

Arbuscular mycorrhizal fungi (AMF) are widespread soil endophytic fungi, forming mutualistic relationships with the vast majority of land plants. Biochar (BC) has been reported to improve soil fertility and promote plant growth. However, limited studies are available concerning the combined effects of AMF and BC on soil community structure and plant growth. In this work, a pot experiment was designed to investigate the effects of AMF and BC on the rhizosphere microbial community of Allium fistulosum L. Using Illumina high-throughput sequencing, we showed that inoculation of AMF and BC had a significant impact on soil microbial community composition, diversity, and versatility. Increases were observed in both plant growth (the plant height by 8.6%, shoot fresh weight by 12.1%) and root morphological traits (average diameter by 20.5%). The phylogenetic tree also showed differences in the fungal community composition in A. fistulosum. In addition, Linear discriminant analysis (LDA) effect size (LEfSe) analysis revealed that 16 biomarkers were detected in the control (CK) and AMF treatment, while only 3 were detected in the AMF + BC treatment. Molecular ecological network analysis showed that the AMF + BC treatment group had a more complex network of fungal communities, as evidenced by higher average connectivity. The functional composition spectrum showed significant differences in the functional distribution of soil microbial communities among different fungal genera. The structural equation model (SEM) confirmed that AMF could improve the microbial multifunctionality by regulating the rhizosphere fungal diversity and soil properties. Our findings provide new information on the effects of AMF and biochar on plants and soil microbial communities.

• The Journal of the Korea Contents Association
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• v.17 no.8
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• pp.1-13
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• 2017

In this paper, a research model was designed to investigate the factors influencing the intention to use of mobile easy payment services in China. Our research model includes the service factors(instant connectivity, economic and security), social factors(subjective norms and image), the user's individual factors(self-efficacy personal innovativeness and suitability), perceived ease of use, perceived usefulness and intention to use. A survey was conducted to collect the data with users who have had the actual using experience about mobile easy payment services. In this research, the data were collected by online survey, and in final analysis, 439 users' questionnaires were used. The empirical paper proves research hypothesis by using SPSS 22.0 and AMOS 23.0. The results of the study are as follows: the mobile easy payment service factors, social factors and the user's individual factors partially give positive effects to perceived ease of use and perceived usefulness; perceived ease of use gives positive effects to perceived usefulness. In addition, perceived ease of use and perceived usefulness have positive effects to on intention to use.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.7
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• pp.1467-1474
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• 2009

What matters in the society of knowledge and information is not that they just know certain facts, but that when faced with new situations, they should be able to develop novel ideas, apply them and do the problems or the tasks confronting them. This cannot be achieved through learning of mere knowledge. Computer programming lessons have shown positive effects on general thinking ability, metacognitive aspects, and logical thinking. The ACM has suggested that 8th grade students at the first level (second year students of middle school) be educated in programming languages such as LOGO to raise their ability to think logically. Previous studies have confirmed educational programming languages such as LOGO and BASIC, which are currently used, are helpful in improving the ability to think logically and to solve problems. However these languages lack connectivity with later learning. Little research has been done on 'Dolittle', an educational programming language, newly developed, using object-oriented notions. Few studies have been made of the effects of 'Dolittle' on the ability to think logically. The following results were obtained. The research didn't lead to a statistically significant improvement of the students' cognitive development level. However, proportional logic and combinational logic, among the six subcategories of logic, improved through the introduction of 'Dolittle' programming lessons. This leads to the conclusion that in the processing of solving the problems given, the students learned by themselves and improved their ability to think logically.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.281-281
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• 2015

Shallow landslide often occurs in areas of this topography where subsurface soil water flow paths give rise to excess pore-water pressures downslope. Recent hillslope hydrology studies have shown that subsurface topography has a strong impact in controlling the connectivity of saturated areas at the soil-bedrock interface. In this study, the physically based SHALSTAB model was used to evaluate the effects of three soil thicknesses (i.e. average soil layer, soil thickness to weathered soil and soil thickness to bedrock soil layer) and subsurface flow reflecting three soil thicknesses on shallow landslide prediction accuracy. Three digital elevation models (DEMs; i.e. ground surface, weathered surface and bedrock surface) and three soil thicknesses (average soil thickness, soil thickness to weathered rock and soil thickness to bedrock) at a small hillslope site in Jinbu, Kangwon Prefecture, eastern part of the Korean Peninsula, were considered. Each prediction result simulated with the SHALSTAB model was evaluated by receiver operating characteristic (ROC) analysis for modelling accuracy. The results of the ROC analysis for shallow landslide prediction using the ground surface DEM (GSTO), the weathered surface DEM and the bedrock surface DEM (BSTO) indicated that the prediction accuracy was higher using flow accumulation by the BSTO and weathered soil thickness compared to results. These results imply that 1) the effect of subsurface flow by BSTO on shallow landslide prediction especially could be larger than the effects of topography by GSTO, and 2) the effect of weathered soil thickness could be larger than the effects of average soil thickness and bedrock soil thickness on shallow landslide prediction. Therefore, we suggest that using BSTO dem and weathered soil layer can improve the accuracy of shallow landslide prediction, which should contribute to more accurately predicting shallow landslides.