• Journal of Ocean Engineering and Technology
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• v.34 no.6
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• pp.394-405
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• 2020

To assess the station-keeping performance of floating structures in the Arctic region, the ice load should be considered along with other environmental loads induced by waves, wind, and currents. However, present methods for performance evaluation in the time domain are not effective in terms of time and cost. An ice load generation module is proposed based on the experimental data measured at the KRISO ice model basin. The developed module was applied to a time domain simulation. Using the results of a captive model test conducted in multiple directions, the statistical characteristics of ice loads were analyzed and processed so that an ice load corresponding to an arbitrary angle of the structure could be generated. The developed module is connected to commercial dynamic analysis software (OrcaFlex) as an external force input. Station-keeping simulation in the time domain was conducted for the same floating structure used in the model test. The mooring system was modeled and included to reflect the designed operation scenario. Simulation results show the effectiveness of the proposed ice generation module and its application to station-keeping performance evaluation. Considering the generated ice load, the designed structure can maintain a heading angle relative to ice up to 4°. Station-keeping performance is enhanced as the heading angle conforms to the drift direction. It is expected that the developed module will be used as a platform to verify station-keeping algorithms for Arctic floating structures with a dynamic positioning system.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.23 no.12
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• pp.1650-1658
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• 2019

In recent years, IoT device and platform become widely popular and the computing performance and capabilities of IoT devices are also getting improved. However, the size and computing resources of IoT devices, especially small single board computer, are limited in a way that the design and implementation of the system should be carefully considered to operate on the devices. Recently, SDR technologies are adapting in IoT devices and can perform various radio systems. Thorough analysis and investigation of computer performances on small single board computer are necessary for its usage. In this paper, we present the results of computing resources measurement and analysis on small single-board computers. At first, we consider to design SDR based spectrum sensing for single board computer, investigate various key factors and propose a design procedure that can affect performance of the system with experiments.

• Journal of the Korea Convergence Society
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• v.12 no.3
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• pp.217-224
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• 2021

Based on the hyper-connectivity of the 4th Industrial Revolution, the paradigm shifts to the sharing economy. Didichuxing has already dominated the platform and is expanding its service to the TaaS 3.0 mobility industry. This paper aimed to suggest the direction of the domestic car-sharing industry and service improvement plan by analyzing Didichuxing. Korea is being cut off from the car-sharing industry, due to conflicts with existing industries and high regulations. It is necessary to balance the protection of existing industries and fostering new industries in the direction of negative regulations. In the future, it is also necessary to study how various fields of the sharing economy will convergence and develop.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.14 no.1
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• pp.29-36
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• 2021

The amount of data generated has been growing exponentially, and the complexity of data has been increasing owing to the advancement of information technology (IT). Big data analysts and engineers have therefore been actively conducting research to minimize the analysis targets for faster processing and analysis of big data. Hadoop, which is widely used as a big data platform, provides various processing and analysis functions, including minimization of analysis targets through Hive, which is a subproject of Hadoop. However, Hive uses a vast amount of memory for data deduplication because it is implemented without considering the complexity of data. Therefore, an efficient algorithm has been proposed for data deduplication of complex structures. The performance evaluation results demonstrated that the proposed algorithm reduces the memory usage and data deduplication time by approximately 79% and 0.677%, respectively, compared to Hive. In the future, performance evaluation based on a large number of data nodes is required for a realistic verification of the proposed algorithm.

• Journal of Digital Convergence
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• v.19 no.2
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• pp.515-522
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• 2021

In this study, 186 remote graduate students from J University were surveyed and interviewed in-depth to see if their satisfaction varies depending on their gender, semester, and major, and the results were as follows. First, the gender satisfaction of remote graduate students was shown to be statistical significance differences between men and women in professors, offline activities, and class evaluations, all of which showed that men were significantly higher than women. Second, the satisfaction level of each semester of remote graduate students was shown to be significantly different in curriculum, LMS, lecture content quality, and offline activities, and tended to increase as the school year went up. Third, the satisfaction level of remote graduate students by major was found to have significant differences in other factors except LMS and class contents, with the highest educational administration. The results of this study are expected to be used as basic data to improve elements absolutely necessary for student-centered education, such as curriculum of remote graduate schools, establishment of learning platform (LMS), and development and production of lecture contents.

• Molecules and Cells
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• v.44 no.1
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• pp.50-62
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• 2021

Among all cancer types, lung cancer ranks highest worldwide in terms of both incidence and mortality. The crosstalk between lung cancer cells and their tumor microenvironment (TME) has begun to emerge as the "Achilles heel" of the disease and thus constitutes an attractive target for anticancer therapy. We previously revealed that crosstalk between lung cancer cells and endothelial cells (ECs) induces chemoresistance in multicellular tumor spheroids (MCTSs). In this study, we demonstrated that factors secreted in response to crosstalk between ECs and lung cancer cells play pivotal roles in the development of chemoresistance in lung cancer spheroids. We subsequently determined that the expression of hypoxia up-regulated protein 1 (HYOU1) in lung cancer spheroids was increased by factors secreted in response to crosstalk between ECs and lung cancer cells. Direct interaction between lung cancer cells and ECs also caused an elevation in the expression of HYOU1 in MCTSs. Inhibition of HYOU1 expression not only suppressed stemness and malignancy, but also facilitated apoptosis and chemosensitivity in lung cancer MCTSs. Inhibition of HYOU1 expression also significantly increased the expression of interferon signaling components in lung cancer cells. Moreover, the activation of the PI3K/AKT/mTOR pathway was involved in the HYOU1-induced aggression of lung cancer cells. Taken together, our results identify HYOU1, which is induced in response to crosstalk between ECs and lung cancer cells within the TME, as a potential therapeutic target for combating the aggressive behavior of cancer cells.

• The Journal of the Korea Contents Association
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• v.20 no.12
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• pp.13-22
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• 2020

This study aims to find out success factors of crowdfunding on movie projects. For empirical analysis, we collected 583 data of the movie projects from the crowdfunding platform 'Tumblbug'. To figure out the success factors, we examined effects of 10 independent variables on 1 dependent variable. The independent variable includes target amount, project information, reward options, creator funding power, editor recommendation, creator contents power, movie type, number of comments, number of replies, and number of SNS information. The final achievement rate of crowdfunding was set as dependent variable. This study found that the target amount, number of text information, number of video information, editor recommendation, number of backers' reply, and number of SNS information had a significant impact on the achievement rate of the movie crowdfunding project. This study has implications in that it has discovered a variable of editor recommendation and the number of SNS information, and both of them have a positive effect on crowdfunding achievement.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.15 no.6
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• pp.2148-2167
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• 2021

The proliferation of the Internet of Things (IoT) technologies and applications, especially the rapid rise in the use of mobile devices, from individuals to organizations, has led to the fundamental role of secure wireless networks in all aspects of services that presented with many opportunities and challenges. To ensure the CIA (confidentiality, integrity and accessibility) security model of the networks security and high efficiency of performance results in various resource-constrained applications and environments of the IoT platform, DDO-(data-driven operation) based constructions have been introduced as a primitive design that meet the demand of high speed encryption systems. Among of them, the TMN-family ciphers which were proposed by Tuan P.M., Do Thi B., etc., in 2016, are entirely suitable approaches for various communication applications of wireless mobile networks (WMNs) and advanced wireless sensor networks (WSNs) with high flexibility, applicability and mobility shown in two different algorithm selections, TMN64 and TMN128. The two ciphers provide strong security against known cryptanalysis, such as linear attacks and differential attacks. In this study, we demonstrate new probability results on the security of the two TMN construction versions - TMN64 and TMN128, by proposing efficient related-key recovery attacks. The high probability characteristics (DCs) are constructed under the related-key differential properties on a full number of function rounds of TMN64 and TMN128, as 10-rounds and 12-rounds, respectively. Hence, the amplified boomerang attacks can be applied to break these two ciphers with appropriate complexity of data and time consumptions. The work is expected to be extended and improved with the latest BCT technique for better cryptanalytic results in further research.

• The Journal of Industrial Distribution & Business
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• v.12 no.6
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• pp.75-88
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• 2021

Purpose: This research aimed at exploring the functions of consumers' perceiving approach and avoidance roles and their feeling anger and disgust in the effect of the two types of self-discrepancy at social identity such as the ideal self-discrepancy and the ought self-discrepancy on within-self domain versus across-self domain consumption. Research design, data, and methodology - This study divided the self-discrepancy group into the ideal self-discrepancy and the ought self-discrepancy group as experimental groups for empirical study. Self-discrepancy type between-subjects design was used to develop two types of questionnaire according to the type of experimental groups. The platform, 'questionnaire stars' of 'WeChat' in China was used to collect 103 data from the ideal self-discrepancy group and 102 from the ought self-discrepancy group for empirical study. T-test and the structural equation model in Amos 21 were used to verify hypotheses developed through theoretical review. Results - First, ideal self-discrepancy positively affected the role-approaching goal and anger. Second, ought self-discrepancy positively affected the role-avoiding goal and disgust. Third, the role-approaching goal and anger positively influenced on the within- versus across- domain consumption. Fourth, the disgust negatively influenced on the within- versus across- domain consumption, however the role-avoiding goal did not influence on the consumption. Fifth, there was the mediation roles of anger (disgust) in the effects of ideal (ought) self-discrepancy on the consumption. Conclusions - When consumers feel anger at the ideal self- discrepancy induced by in-group, it is necessary for the marketers to promote their product brand used by the in-group. They should develop and advertise the messages priming the ideal self-discrepancy and the anger to increase the intent to purchase or use their product brand when the in-group members have used the brand by relating the brand to their social identity concerned with the ideal self-discrepancy. However, marketers should help consumers feel disgust by developing and advertising the messages expressing the ought self-discrepancy to lead the consumers to the place of purchasing or using their product brand when the members have used the brand based on keeping the consistence between the brand and other social identity not related to the ought self-discrepancy.

• Journal of the Korea Society of Computer and Information
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• v.26 no.8
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• pp.229-237
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• 2021

This paper aims to study the using motivation and influencing factors of Chinese users' participation in live stream shopping through theoretical and empirical analysis, so as to evaluate the change in users' needs and improve marketing strategies. In doing so, I conducted a questionnaire survey for Chinese live stream shopping users and collected the required data. For empirical analysis, I used SPSS and AMOS software to carry out descriptive analysis, reliability and validity analysis and structural equation model analysis (SEM) to test the hypothesis. The results of the analysis showed that core competency and brand personality of the short video industry have a significant impact on user and customer perceived value, thus influencing users' using motivation. That is, users do not blindly follow live stream shopping but make their active choice. Therefore, it is suggested that live stream shopping platform should strengthen the e-commerce attributes and eradicate "the sense of false satisfaction", in order to achieve the effective communication of information. On the other hand, to stimulate the purchase motivation of users, the brand should build up its personality, and enhance user and customer perceived value in cyber marketing.