• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.2
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• pp.222-228
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• 2016

We provide an aggressive spatial reuse scheme exploiting the space sensed busy when neighboring 802.11 stations radiate radio wave in omni-directions. For this purpose, we develop four strategies, i.e., disruptive RTS, busy random backoff, zero padding, and unavailable pair management. The simulation results show that the proposed scheme can improve the aggregate network throughput from 14% to 50% while the station adopting the proposed scheme coexists with the legacy stations.

• Nuclear Engineering and Technology
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• v.51 no.1
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• pp.73-83
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• 2019

It is important to clarify the mechanisms of molten-fuel-pool sloshing behavior that might be encountered during a core disruptive accident of sodium-cooled fast reactors. In this study, motivated by acquiring some evidence for understanding the characteristics of this behavior at more realistic conditions, a number of experiments are newly performed by injecting nitrogen gas into a water pool with the accumulation of solid particles. To achieve comprehensive understanding, various parameters including particle bed height, particle size, density, shape, gas pressure along with the gas-injection duration, were employed. It is found that due to the different interaction mechanisms between solid particles and the gas bubble injected, three kinds of regimes, termed respectively as the bubble-impulsion dominant regime, the transitional regime and the bed-inertia dominant regime, could be identified. The performed analyses also suggest that under present conditions, all our experimental parameters employed can have noticeable impact on the regime transition and resultant sloshing intensity (e.g. maximum elevation of water level at pool peripheries). Knowledge and fundamental data from this work will be used for the future verifications of fast reactor severe accident codes in China.

• Journal of Distribution Science
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• v.20 no.10
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• pp.93-103
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• 2022

Purpose: This study aims to determine the relationship between disruptive factors and customer satisfaction at chain stores. Survey-based questionnaires were designed in the distribution technique to measure the findings in this study. Research design, data, and methodology: In terms of the sampling technique, the researchers adopted the simple random sampling technique with a total of 200 sample sizes. For the statistical method, the researchers applied multiple linear regression analysis to determine the potential factors that affect customer satisfaction at chain stores. The analysis of this study measured how product quality, pricing policies of chain stores, design and layout, responsiveness, and location of chain stores impart their roles in customer satisfaction. Results: This study found a significant relationship between the product quality and location of chain stores on customer satisfaction. In addition, the responsiveness, pricing policy, and physical design of chain stores impart an insignificant role in customer satisfaction. However, it is proven that the location of chain stores and product quality positively impact customer satisfaction. Conclusions: The study is geographically limited to the region of Karachi, Pakistan. Therefore, the findings may differ in the context of study implications in the other areas.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.32 no.2
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• pp.20-28
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• 2024

The purpose of this study is to investigate the impact of negative emotions on the intention to share negative experiences caused by unruly passengers on flights. 163 questionnaires were collected and an SEM model was used to measure the relationship between passengers' negative emotions and sharing intentions. We empirically analyzed the impact of unruly passenger behavior on social media sharing intention through negative emotions, airline trust, and satisfaction with service recovery. Theoretically, we established a clear causal relationship between these variables. The results of this study shed light on the importance of developing a sustainable service strategy for passengers by analyzing the impact of negative emotions and sharing intentions. Based on our findings, we recognized that airlines should respond to disruptive behavior while understanding the negative emotional feelings of surrounding passengers. Therefore, this study strongly recommends that airlines should respond appropriately to in-flight disruptive behavior and ensure that passengers' negative emotions do not damage the overall reputation and image of the airline.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.5 no.1
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• pp.141-149
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• 1994

The prevalence rates of disruptive behavior disorders(attention deficit hyperactive disorder, conduct disorder and oppositional defiant disorder, ADHD, CD and ODD respectively) were studied in 780 elementary school children from 4th to 6th grades. The results are summarized as follows : 1) The prevalences rates of ADHD were in boys 10.3%(45/436), 4.1%(14/344) in girls and the overall prevalence rate was 7.6%(59/780). 2) The prevalence rates of CD were 5.0%(22/436) in boys, 2.3%(8/344) in girls and the overall prevalence rate was 3.8%(30/780). 3) The prevalence rates of ODD were 5.7%(25/436) in boys, 2.3%(8/344) in girls and the overall prevalence rate was 4.2%(33/780). 4) These three disorders were significantly more common in boys than in girls. 5) There were no significant differences in the prevalence rates of ADHD, CD and ODD by grades or urban-rural status. 6) The comorbidity of ADHD was also explored, 3.5% (2/59) of ADHD also had CD, 13.6% (8/59) had both CD and ODD. 7) The mild forms of these three disorders were about two times more common than typical forms.

• Journal of Digital Convergence
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• v.13 no.5
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• pp.119-127
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• 2015

Although it was very long since companies and organizations have been interested in technological innovation or management innovation and many of them have been investing on innovation in convergence industry environment, they could not take differentiated competency and competitive advantage so that they were fallen behind from market by new trends. This research is aiming at deduction of strategies for corporations to keep continuously differentiated competitiveness and competitive advantage. It suggested open innovation activities as basic independent variables. It added global technological alliance known for Open Innovation Alliances to independent variables too. It suggested platform leadership emerging between open innovation activities and digital ecosystem and 6 encroachment types from disruptive innovation theory as control variables. It suggested dynamic competitive advantage as dependent variable for explaining dynamic properties of environment. It analyzed case from 11 researches of open innovation activities, categorized them and verified the appropriacy of the variables. This research contributes to new direction for derivation of strategies and methodologies by which corporations keep competitive advantage in dynamic convergence environment.

• KIPS Transactions on Computer and Communication Systems
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• v.7 no.12
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• pp.295-300
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• 2018

The rapid development of IT, many conventional passive jobs have been automated. This automation increases the leisure time of many people and various services are being developed for them. In addition, with the advent of smart devices that are compact and portable, it is possible to use various internet services without any time and place discretion. Various studies based on virtualization are under way to efficiently store and process large data generated by many devices and services. Desktop Storage Virtualization (DSV), which integrates and provides users with on-premise-based distributed desktop resources during these studies, uses virtualization to consolidate unused resources within distributed, legacy desktops. This DSV is very important for providing high reliability to users. In addition, research on hierarchical structure and resource integration for efficient data distribution storage processing in a distributed desktop-based resource integration environment is underway. However, there is a lack of research on efficient operation in case of server failure in on-premise resource integration environment. In this paper, we propose Non-disruptive Server Management (NSM) which can actively cope with the failure of desktop server in distributed desktop storage environment based on on-premise. NSM is easy to add and remove desktops in a desktop-based integrated environment. In addition, an alternative server is actively performed in response to a failure occurrence.

• Proceedings of the Korea Association of Information Systems Conference
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• 2005.12a
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• pp.275-280
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• 2005

Net present value (NPV) and return on investment (ROI) are commonly used to evaluate investment in new technologies. Sometimes, however, measuring the value of investment in new IT becomes very difficult due to its wide scope of application coupled with embedded options in its adoption. Therefore, comprehensive but easily understandable methodologies are needed to solve the complicated problems resulting from the complexity of new technologies. This paper employs a real option analysis to evaluate RFID adoption in the supply chain. Real options analysis should be a better way to evaluate a disruptive technology like RFID.

• Korean System Dynamics Review
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• v.6 no.1
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• pp.17-32
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• 2005

An agricultural commodity production cycle model consisting of corn, beef, and dairy sectors was constructed for the purpose of exploring the propagating effects of large-scale disruptive events. In an initial proof-of-concept exercise, we considered an agricultural disruption scenario in which foot-and-mouth disease (FMD) is introduced into the U.S., causing a large-scale outbreak of the disease in both beef and dairy cattle. The magnitude of disruption to the beef and dairy sectors are presented under the existing W response policy and then improvements under two alternative policies are shown.

• The Korean Journal of Mycology
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• v.49 no.3
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• pp.379-383
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• 2021

Lactuca serriola L. (syn. L. scariola L.), commonly known as prickly lettuce, invaded Korea in the late 1970s. The plant has since become widely naturalized and disruptive to native plant communities. In May 2020, downy mildew infections were observed on L. serriola in Gimje-si, Korea. Molecular phylogenetic and morphological analyses identified the causal agent as Bremia lactucae. This is the first report of B. lactucae infection on L. serriola in Korea.