• The KIPS Transactions:PartA
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• v.12A no.1 s.91
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• pp.23-30
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• 2005

Causal order of message delivery algorithm ensures that every transmitted message is delivered in causal order. It should be noted that control information should be transmitted with each message in order to enforce causal order. Hence, it is important to reduce this communication overhead because the impact of the overhead increases proportionally with the number of related processes. In this paper we propose and evaluate effective a ${\Delta}-causal$ order algorithm for multimedia data which have real-time property. To reduce transmission overhead, proposed algorithm eliminates redundant information as early as possible which is not explicitly required for preserving causal order. Average communication overhead of our algorithm is much smaller than other existing algorithms.

• The Journal of the Korea Contents Association
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• v.17 no.5
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• pp.499-508
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• 2017

For analyzing the performance determinants of ODA projects in a technical and vocational education and training, this research analyzed the performance determinants of effectiveness representing the direct benefit and impact representing the long-term development effects of ODA project using FsQCA. As a result, the effectiveness of ODA project is achieved when relevance, sustainability and impact are high, or relevance, impact and efficiency are high. The impact of ODA project is achieved when relevance, sustainability and effectiveness are high, or relevance, effectiveness and efficiency are high. Two solutions for achieving effectiveness and two solutions for achieving impact show equifinality. The core factors for achieving effectiveness are relevance and impact, and the core factors for achieving impact are relevance and effectiveness. Also sustainability and efficiency are substitutability. A single causal variable can not have an effect on the ODA performance, but combined more than three causal variables can have an effect on the ODA performance. Therefore this research verified that collectives of causal variables rather than single causal variable should be considered to achieve the performance of ODA project in technical and vocational education and training.

• Asia-Pacific Journal of Business
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• v.15 no.1
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• pp.113-129
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• 2024

Purpose - This study aims to empirically identify the quantitative effects of work from home (WFH) on employee productivity using field data. Design/methodology/approach - Based on large-scale field data from a South Korean company which introduced the WFH arrangement in 2020, we conducted fixed effect and moderating effect analyses using individual-level panel data over sixty-three weeks. Findings - The empirical analysis generated several findings. It was found that overall, WFH has a positive effect on productivity. However, the productivity impact of WFH was found to vary depending on task characteristics. Specifically, WFH led to over 20% increase in productivity for simple and repetitive tasks. On the other hand, no significant productivity impact was observed for professional and knowledge-based tasks. Research implications or Originality - As the first study based on field data from South Korea, this study offers convincing causal evidence of the moderating impact of task characteristics on the relationship between WFH and productivity. Further, the above findings provide managers with practical insights concerning their work arrangement decisions.

• International Journal of Advanced Culture Technology
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• v.8 no.4
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• pp.161-166
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• 2020

The primary aim of this paper is to analyze the resultative adjunct clause, i.e., (thus/thereby/hence) ~ing participle and provide explicit syntactic, semantic and sociolinguistic explanation on the question what causes the cause-focused causal construction with resultative (thus/thereby/hence) ~ing participle in English. What comes first is either cause or effect clause. This study explores the recent style shift of causal constructions from the effect-focused pattern to the cause-focused pattern. In this study, we argue that the increasing number of the cause-focused main clause with a resultative ~ing participle clause shows the process of the style evolution improving speech/wring style in many respects including syntactic simplification, clarification of the sentence meaning with impact on the focused clauses, and improvement of the flow of speech/writing. The style shift found in the English resultative adjunct clauses, i.e., (thus/hence/thereby) ~ing participle constructions prove to be the style evolution from syntactic, semantic and sociolinguistic point of views.

• Journal of Korean Academy of Nursing
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• v.52 no.4
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• pp.451-463
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• 2022

Purpose: This study examined the reciprocal relationships between depression and income, and gender differences in these relationships among older adults in South Korea. Methods: Using 2015 to 2019 of the Korea Welfare Panel Study (KoWePS), we studied 6,070 older adults (2,394 men and 3,676 women) aged 60 years over in 2015. The generalized estimating equation was employed to explore the effect of an individual income on depression and the reverse causal link-that of depression on income. Results: The study found the reciprocal relationships between income and depression. Income has a significant impact on depression. Higher-income was linked to decreased risks of the Center for Epidemiologic Studies Depression (CES-D) scores among older adults (B = - 0.121, p < 0.001). Estimates of the reverse causal link show that higher CES-D scores were also linked to income reduction among Korean older adults (B = - 0.007, p < 0.001). In addition, we also observed gender differences in the impact of income on depression but not in the reverse causal link. Income has more detrimental to psychological consequence for older men (B = - 0.108, p < 0.001) than older women (B = - 0.057, p < 0.001). Conclusion: The finding implies that both psychological and social protection policies for the elderly are needed in view of gender perspective.

• Communications for Statistical Applications and Methods
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• v.23 no.1
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• pp.1-20
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• 2016

Causal inference methodologies have been developed for the past decade to estimate the unconfounded effect of an exposure under several key assumptions. These assumptions include, but are not limited to, the stable unit treatment value assumption, the strong ignorability of treatment assignment assumption, and the assumption that propensity scores be bounded away from zero and one (the positivity assumption). Of these assumptions, the first two have received much attention in the literature. Yet the positivity assumption has been recently discussed in only a few papers. Propensity scores of zero or one are indicative of deterministic exposure so that causal effects cannot be defined for these subjects. Therefore, these subjects need to be removed because no comparable comparison groups can be found for such subjects. In this paper, using currently available causal inference methods, we evaluate the effect of arbitrary cutoffs in the distribution of propensity scores and the impact of those decisions on bias and efficiency. We propose a tree-based method that performs well in terms of bias reduction when the definition of positivity is based on a single confounder. This tree-based method can be easily implemented using the statistical software program, R. R code for the studies is available online.

• Journal of Korea Society of Industrial Information Systems
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• v.11 no.5
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• pp.1-10
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• 2006

This study constructs a causal relationship model of balance scorecard(BSC) performance in supply chain management(SCM). According to the results, the sample companies show the causal relationship of learning and growth performance, internal process performance, customer performance, and financial Performance indices in SCM. And this study implies that BSC performance indices gives, through direct causal relations among them, impact on the ultimate financial performance of firms.

• Korea Journal of Hospital Management
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• v.7 no.2
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• pp.1-23
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• 2002

D. W. Organ(1977) published a paper about the importance of Organizational Citizenship Behavior(OCB) in an organization. Since then, the studies of OCB have been continuously increased. As recent business environment has changed with rapidity and uncertainty, OCB for the improvement performance of organization should be more emphasized. Role behaviors of organization are divided into two parts such as in-role behavior and extra-role behavior. In recent, although the researches about extra-role behavior have been studied, they are still not sufficient. This study attempted to examine relationships between organizational culture, organizational commitment and organizational citizenship behavior, Sample was 193 employee engaged in hospitals of Pusan. In this study I chose four factor(affective, conservative, task and innovative culture) of organizational culture and three factors (affective, continuous and normative commitment) of organizational commitment and five factors(altruism, conscientiousness, courtesy, civic virtue and sportsmanship) with regard to organization citizenship behavior. The major findings of the empirical research are as follows ; 1. The Causal relation of dimensions of organizational culture and dimensions of OCB. 1) Affective culture has significant impact on courtesy, civic virtue of OCB. 2) Conservative culture has no significant impact on all of OCB. 3) Task culture has significant impact on conscientiousness, civic virtue, sportsmanship of OCB. 4) Innovative culture has no significant impact on courtesy, civic virtue of OCB. 2. The Causal relation of dimensions of organizational commitment and dimensions of OCB. 1) Affective commitment has significant impact on all of OCB. 2) Continuous commitment has no significant impact on all of OCB. 3) Normative commitment has significant impact on courtesy, civic virtue of OCB. In brief, though this study has several limitations in research design and methods, the results suggest that organizational culture of hospitals and organizational comitment of hospitals shows a strong relationship to the organization citizenship behavior.

• IE interfaces
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• v.24 no.3
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• pp.196-209
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• 2011

In This Study, New Product Development Activities, Innovation Activities, Technical Cooperation Activities may have an Impact on Competitive Advantage, Development Performance and Business Performance. The aim of Empirical Analyze is to identify the Structural Causal Relationship among the Activities and Performance Factors. We get the Results as Follows : New Product Development Activities have a Positive Impact on Competitive Advantage as well as the Development Performance. Technological Innovation Activities have a Positive Impact on Competitive Advantage, and do not have enough Impact on the Development Performance. Technical Cooperation Activities have a Positive Impact on the Development Performance, and do not have enough Impact on the Competitive Advantage, Competitive Advantage has a Positive Impact on the Development Performance as well as the Business Performance. Development Performance has a Positive Impact on the Business Performance.

• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.163-163
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• 2023

Flooding has become an increasing event which is one of the major natural disasters responsible for direct economic damage in South Korea. Driven by climate change, precipitation extremes play significant role on the flood damage and its further increase is expected to exacerbate the socioeconomic impact in the country. However, the empirical evidence associating changes in precipitation extremes to the historical flood damage is limited. Thus, there is a need to assess the causal relationship between changes in precipitation extremes and flood damage, especially in agricultural region like Chungcheong region in South Korea. The spatial and temporal changes of precipitation extremes from 10 synoptic stations based on daily precipitation data were analyzed using the ClimPACT2 tool and Mann-Kendall test. The four precipitation extreme indices consisting of consecutive wet days (CWD), number of very heavy precipitation wet days (R30 mm), maximum 1-day precipitation amount (Rx1day), and simple daily precipitation intensity (SDII), which represent changes in intensity, frequency, and duration, respectively, and the time series data on flooded area and flood damage from 1985 to 2020 were used to investigate the causal relationship in the ARDL-ECM framework and pairwise Granger causality analysis. The trend results showed that majority of the precipitation indices indicated positive trends, however, CWD showed no significant changes. ARDL-ECM framework showed that there was a long-run relationship among the variables. Further analysis on the empirical results showed that flooded area and Rx1day have significant positive impacts on the flood damage in both short and long-runs while R30 mm only indicated significant positive impact in the short-run, both in the current period, which implies that an increase in flooded area, Rx1day, and R30 mm will cause an increase in the flood damage. The pairwise Granger analysis showed unidirectional causality from the flooded area, R30 mm, Rx1day, and SDII to flood damage. Thus, these precipitation indices could be useful as indicators of pluvial flood damage in Chungcheong region of South Korea.