• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.10
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• pp.4015-4033
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• 2015

The future mobile networks consist of hyper-dense heterogeneous and small cell networks of same or different radio access technologies (RAT). Integrating mobile networks of different RATs to provide seamless and smooth mobility service will be the target of future mobile converged network. Generally, handover from high-speed networks to low-speed networks faces many challenges from application perspective, such as abrupt bandwidth variation, packet loss, round trip time variation, connection disruption, and transmission blackout. Existing inter-RAT handover solutions cannot solve all the problems at the same time. Based on the high-layer convergence sublayer design, a new receiver-aided soft inter-RAT handover is proposed. This soft handover scheme takes advantage of multihoming ability of multi-mode mobile station (MS) to smooth handover procedure. In addition, handover procedure is seamless and applicable to frequent handover scenarios. The simulation results conducted in UMTS-WiMAX converged network scenario show that: in case of TCP traffics for handover from WiMAX to UMTS, not only handover latency and packet loss are eliminated completely, but also abrupt bandwidth/wireless RTT variation is smoothed. These delightful features make this soft handover scheme be a reasonable candidate of mobility management for future mobile converged networks.

• Journal of the Ergonomics Society of Korea
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• v.33 no.2
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• pp.77-86
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• 2014

Objective: The purpose of this study is to grasp the fundamental structure of incident occurrence in nuclear organizations based on system thinking, and analyze how various causes are interrelated in terms of the causal loop diagram. Background: The recent domestic and overseas nuclear power plant-related incidents and accidents are directly or indirectly associated with safety culture, and thus effective plans for the improvement of safety culture are being called for. While the safety of a nuclear power plant is highly dependent upon technology and equipment, the utilization, maintenance and inspection of the technology and equipment are conducted by workers of the nuclear power plant. Method: Methodology of system thinking perspective using causal loop analysis. Results: As a result of the analysis, first, it turned out that the fundamental cause of incident occurrence in nuclear organizations is time constraint. Second, if a workload of workers increases, their adherence to regulations and procedures comes to be reduced due to time constraint. Third, it is needed, through organizational learning education, to increase actions made from thoughts considering safety as the utmost priority in advance. Fourth, it is necessary to improve professionalism by enhancing educational programs for new workers, and to develop various scenarios with which they can cope with certain situations. Application: This paper provides a base for system dynamics simulation model for future study.

• Journal of the Korean Ceramic Society
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• v.55 no.4
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• pp.307-324
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• 2018

Rechargeable lithium-ion batteries (LIBs) have been rapidly expanding from IT based applications to uses in electric vehicles (EVs), smart grids, and energy storage systems (ESSs), all of which require low cost, high energy density and high power density. The increasing demand for LIBs has resulted in increasing price of the lithium source, which is a major obstacle to wider application. To date, the possible depletion of lithium resources has become relevant, giving rise to the interest in Na-ion batteries (NIBs) as promising alternatives to LIBs. A lot of transition metal compounds based on conversion-alloying reaction have been extensively investigated to meet the requirement for the anodes with high energy density and long life-time. In-depth understanding the electrochemical reaction mechanisms for the transition metal compounds makes it promising negative anode for NIBs and provides feasible strategy for low cost and large-scale energy storage system in the near future.

• Proceedings of the Korea Water Resources Association Conference
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• 2018.05a
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• pp.154-154
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• 2018

To interpret the climate projections for the future as well as present, recognition of the consequences of the climate internal variability and quantification its uncertainty play a vital role. The Korean Peninsula belongs to the Far East Asian Monsoon region and its rainfall characteristics are very complex from time and space perspective. Its internal variability is expected to be large, but this variability has not been completely investigated to date especially using models of high temporal resolutions. Due to coarse spatial and temporal resolutions of General Circulation Models (GCM) projections, several studies adopted dynamic and statistical downscaling approaches to infer meterological forcing from climate change projections at local spatial scales and fine temporal resolutions. In this study, stochastic downscaling methodology was adopted to downscale daily GCM resolutions to hourly time scale using an hourly weather generator, the Advanced WEather GENerator (AWE-GEN). After extracting factors of change from the GCM realizations, these were applied to the climatic statistics inferred from historical observations to re-evaluate parameters of the weather generator. The re-parameterized generator yields hourly time series which can be considered to be representative of future climate conditions. Further, 30 ensemble members of hourly precipitation were generated for each selected station to quantify uncertainty. Spatial map was generated to visualize as separated zones formed through K-means cluster algorithm which region is more inconsistent as compared to the climatological norm or in which region the probability of occurrence of the extremes event is high. The results showed that the stations located near the coastal regions are more uncertain as compared to inland regions. Such information will be ultimately helpful for planning future adaptation and mitigation measures against extreme events.

• Korean Journal of Adult Nursing
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• v.20 no.2
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• pp.280-295
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• 2008

Purpose: This ethnography in communication aimed to explore the changes in consciousness on time and temporality as an elderly became older. This study focused on time as a primary message systems of Edward Hall. Methods: The assumption of the study was that the aging body as an expression of biological time is a meta of physical, personal, and social time. Data were collected from iterative fieldwork in a clan between Jan, 1990 and April, 2007. The key informants were 13 women and men aged 70 years old or more at the beginning of study. Changes in physical time and temporality as the women's body declined in its physical function was analyzed. As the cultural context, informants' every life and the history of the clan were also analyzed. Results: The meta-time of the informants were constituted as follows: In the low-contextual dimension, physical time perceived as longer and personal time perceived as shorter than they were young; In high-contextual dimension, informant and residents had a polychronic perspective and aged-centered time perspectives.; In the supernatural dimension of time, sacred time were reinforced by rituals. Informants extended temporality to their springs' world and ancestors' world. Conclusion: As the informants recognized slugged body movements and time-limited present life, their views on their life world towards the future of spring and of the sacred world of ancestors. Thereby, their identity as a member of a clan was reinforced. This result informed us on what we should focus on when caring with older women.

• Asia-Pacific Journal of Business
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• v.14 no.3
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• pp.115-147
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• 2023

Purpose - This study examines previous research on organizational silence for several decades since the concept of organizational silence was firstly suggested in 2000. In this study, based on previous studies on organizational silence published in domestic and international journals from 2010 to 2022, research trends were analyzed, issues were derived, and future research was suggested. Design/methodolgy/approach - The authors searched relevant keywords such as organizational silence, employee silence, employee voice and so on in the domestic as well as international academic database. 63 domestic papers were found, and based on these articles, we analyzed the research trends. Findings - Similar variables were proven with only different contextual samples without any originality in the theoretical perspective. Moreover, studies on the causal relationship between each type of organizational silence and the occurrence of organizational silence over time were also insufficient. In addition, because research on public organizations was limited to police officers and public officials, future research is needed to investigate more different organizational situations. Furthermore, other variables such as personal characteristics and leadership factors were also relatively unexplored. Based on these limitations, future research is needed to consider more diverse demographics, Korean cultural factors, organizational characteristics, and the patterns changes in time. Research implications or Originality - This study suggests limitations as well as future directions by summarizing the previous research on organizational silence which is an emerging issue in global societies and the organizational management filed.

• The Journal of Korean Association of Computer Education
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• v.16 no.6
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• pp.21-32
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• 2013

Since creativity has been emphasized and creative problem solving has also been a big topic recently, various kinds of research works have proceeded. Among them, this paper focuses on abstract thinking and growth mindset, which affect on problem solving. Also, this paper analyzes what kinds of relationships time perspectives and smart-phone addiction have with the two factors and how they influence on them. In order to do so, we survey on 441 primary, middle, high school, and college students. Our analysis results cover the relationships among the two factors, smart-phone addiction level, present-hedonic perspective, and future time perspective. In addition, we analyze the relationship among the factors with a structural equation model. By doing these, we propose educational alternatives in terms of time and plan to improve our adolescent's abstract thinking level, which helps their problem solving skills and their academic achievement.

• East Asian Journal of Business Economics (EAJBE)
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• v.7 no.3
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• pp.1-11
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• 2019

Purposes - This study discusses various aspects of familiarity with the sea and how familiarity with the sea is perceived. This study also summarizes the literature on the factors of previous researches that affect the formation or decision of national image. Research design and methodology - Sea familiarity index was derived from the results of recognition of free association with the sea, friendliness with the sea, association of the sea with life, interest to the sea, Korea's representative marine regions, and sea related emotionalism. The familiarity with the sea (ocean) perceived by foreign visitors or foreigners in the future will be helpful in deriving a comparative research. Results - This study has identified the marine tourism resources, marine ecology, and the cognitive and emotional situations consumers feel that should be developed practically. If a continuous time series research is conducted in the future through these, it will be a chance to provide a basis for consumers' dynamic awareness. Conclusions - Through this study, it is pointed out that the research utilizing the sea and ocean to form national image highly suggested an opportunity to add and utilize new variables academically. This study on the perspective of the formation of national image suggests a new approach to add and utilize new variables to future research using the sea and ocean.

• International journal of advanced smart convergence
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• v.11 no.1
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• pp.55-63
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• 2022

Although research on the leader's or speaker's voice has been continuously conducted, existing research has a single point of view. Sound analysis of voice characteristics has been studied from engineering perspectives, and leadership trait theory has been studied from a business perspective. Convergence studies on leader voice and member cognition are being attempted today. Convergence research on voice has a positive effect on refinement of voice analysis, diversification of voice use, and establishment of voice utilization strategy. This study explains the current flow of research on convergence between speaker's voice and listener's perception, and suggests a direction for the future development of voice fusion research. Furthermore, in connection with AI in the 4th industrial age, new attempts for voice research are sought. First, advances in AI focus on strategically generating the voices needed for individual situations. Second, the voice corrected in real time will support the leader and speaker to utilize the desired voice type. Third, voices through AI based on big data will affect the cognition, attitude and behavior of individual listeners who members, customers, and students in more diverse situations. The purpose and significance of this study is to suggest the way to research the leader's voice recognized by members, and to suggest a method that can be applied in various situations.

• Journal for History of Mathematics
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• v.27 no.1
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• pp.59-66
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• 2014

This interdisciplinary study explores G$\ddot{o}$del's hermeneutics of the relationship between relativity theory and idealistic philosophy in terms of time. For G$\ddot{o}$del, Einstein's contribution to the physical realization of idealistic philosophy would be remarkable. We start with a historical background around G$\ddot{o}$del's paper for Einstein(1949a). From the perspective of G$\ddot{o}$del's cosmology, the second part addresses the relative nature of time, and the next then investigates the rotating model of universes. G$\ddot{o}$del's own results show that the temporal conditions of relativity and idealistic philosophy are satisfiable in the mathematical model of rotating universes. Thus, it could be asserted to travel into any region of the past, present or future, and back again.