• Journal of the Korea Society for Simulation
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• v.32 no.3
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• pp.67-74
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• 2023

A semiconductor fabrication facility(FAB) is one of the most capital-intensive and large-scale manufacturing systems which operate under complex and uncertain constraints through hundreds of fabrication steps. To improve fab performance with intuitive scheduling, practitioners have used weighted-sum scheduling. Since the determination of weights in the scheduling significantly affects fab performance, they often rely on simulation-based decision making for obtaining optimal weights. However, a large-scale and high-fidelity simulation generally is time-intensive to evaluate with an exhaustive search. In this study, we investigated three sampling methods (i.e., Optimal latin hypercube sampling(OLHS), Genetic algorithm(GA), and Decision tree based sequential search(DSS)) for the optimization. Our simulation experiments demonstrate that: (1) three methods outperform greedy heuristics in performance metrics; (2) GA and DSS can be promising tools to accelerate the decision-making process.

• Journal of The Korean Society of Integrative Medicine
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• v.11 no.2
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• pp.77-86
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• 2023

Purpose : This study systematically assessed 9 emotion-function programs for schizophrenic individuals that have been implemented over the past 10 years in Korea and abroad, with the objective of providing clinical grounds and data for further programs. Methods : This study identified 2,558 studies from among those registered in the RISS, KISS, EMbase, PubMed and Scopus databases from 2013 to September 2023, using 'schizophrenia' AND 'emotion' AND ('program' OR 'therapy') as keywords. Of the 2,558 studies retrieved from electronic databases, 602 duplicate papers were excluded. After this process, 1,915 papers that did not meet the study's inclusion and exclusion criteria were excluded based on their titles and abstracts. Following a review of the texts of the remaining 41 papers, nine papers were finally selected, excluding 32 papers according to the selection and exclusion criteria. Results : Programs for the emotional function of patients with schizophrenia have continued to be researched. The results of an evaluation on the quality of the selected literature confirmed that a majority of the reviewed items were "uncertain", confirming that there was a risk of bias. The interventions for emotions included art, cognitive-behavioral, and physical programs, of which art programs were frequently applied. Most of the interventions were implemented in hospitals. The dependent variables for evaluating emotions included emotional expression, depression, anxiety, and positive emotions, and among them, emotional expression was used most frequently. Accordingly, the Berkeley expressivity questionnaire was commonly used as an evaluation tool. Conclusion : This study is significant for intending to analyze domestic and overseas programs for the emotions of patients with schizophrenia, thereby proposing the direction for planning and applying interventions in clinical settings. In follow-up studies, it will be necessary to develop a protocol that confirms interventions according to the settings and patient characteristics of programs and expands the scope of literature reviews.

• Journal of Korea Trade
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• v.26 no.6
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• pp.41-60
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• 2022

Purpose - The policy implications of free trade agreements have traditionally been a matter of debate among economists. The official signing of the Korea-China Free Trade Agreement provides economists with a quasi-natural experiment to analyze the FTA's policy effects. This article aims to more accurately understand the impact of Korea's FTA accession on the macro economy. Design/methodology - This study adopts the counterfactual method based on panel data to find common factors in the generation process of macro data to fit the counterfactual path, to accurately evaluate the effect of the macro policy. Findings - Our research results show that the signing of the Korea-China FTA has a relatively significant short-term positive effect on Korea's economic growth. On average, Korea's real GDP growth rate has increased by 2.1%. This study finds evidence in support of FTA signing not having a significant impact on Korea's GDP growth in the long run. Additionally, we evaluated the impact of the FTA on Korea's imports and exports and found that it had a significant positive impact in the short term, but the trade effect of the FTA is significantly affected by the external macro-environment. Originality/value - First, this study uses macro panel data at the national level to examine the impact of the Korea-China FTA on Korea, and more accurately describes the policy effect of the FTA. Second, our empirical results show that the Korea-China FTA policy impact is subject to occasional changes in the external environment, such as the geopolitical conflict (crisis) between Korea and China, and the US-China trade war. Finally, the analysis shows that the short-term effect of FTA is significant but the long-term is uncertain, which provides empirical evidence for the debate on whether joining FTA can promote national economic growth.

• The Journal of Bigdata
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• v.7 no.1
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• pp.75-87
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• 2022

This study investigates a dynamic flexible flow shop scheduling problem under uncertain rework operations for an automobile pipe production line. We propose a weighted dispatching rule (WDR) based on the multiple dispatching rules to minimize the weighted sum of average flowtime and tardiness. The set of weights in WDR should be carefully determined because it significantly affects the performance measures. We build a discrete-event simulation model and propose a genetic algorithm to optimize the set of weights considering complex and variant operations. The simulation experiments demonstrate that WDR outperforms the baseline dispatching rules in average flowtime and tardiness.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.4D
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• pp.617-626
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• 2006

The purpose of contingency estimate is to manage the increase in construction cost and the extension of the term of works due to the inevitable occurrence of uncertain situations. The aim of contingency strategies have two intentions. One thing, can be called a passive strategy, gets ready for construction cost increase due to uncertainty factors, the other thing, can be called a active strategy, gets rid of the obstruction factors of work prior to construction performance. Therefore, from the view point of medium and long term, there is necessary to accumulate data in conjunction with design modification cases and carefully analyze uncertainty factors from construction types and characters. Therefore, this thesis will analyze design modification case at a special work such as highway and select factors that affect construction cost and present contingency estimate process using regression analysis.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.37 no.1
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• pp.57-65
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• 2024

In a fire-resistant structure, uncertainties arise in factors such as ventilation, material elasticity modulus, yield strength, coefficient of thermal expansion, external forces, and fire location. The ventilation uncertainty affects thefactor contributes to uncertainties in fire temperature, subsequently impacting the structural temperature. These temperatures, combined with material properties, give rise to uncertain structural responses. Given the nonlinear behavior of structures under fire conditions, calculating fire fragility traditionally involves time-consuming Monte Carlo simulations. To address this, recent studies have explored leveraging machine learning algorithms to predict fire fragility, aiming to enhance efficiency while maintaining accuracy. This study focuses on predicting the fire fragility of a steel moment frame building, accounting for uncertainties in fire size, location, and structural material properties. The fragility curve, derived from nonlinear structural behavior under fire, follows a log-normal distribution. The results demonstrate that the proposed method accurately and efficiently predicts fire fragility, showcasing its effectiveness in streamlining the analysis process.

• Korean Journal of Construction Engineering and Management
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• v.9 no.1
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• pp.187-198
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• 2008

There are usually plenty of material inventories in a construction site. More inventories can meet unexpected demands, and also they may have an economical advantage by avoiding a probable escalation of raw material costs. On the other hand, these inventories also cause negative aspects to increase costs for storing redundant inventory as well as decreasing construction productivity. Therefore, a proper method of deciding an optimal level of material inventories while considering dynamic variations of resources under uncertainty is very crucial for the economical efficiency of construction projects. This research presents a stochastic modelling method for construction operations, particularly targeting a work process involving on-site fabrication of raw materials like iron-rebar process (delivery, cut and assembly, and placement). To develop the model, we apply the concept of factory physics to depict the overall components of a system. Then, an optimal inventory management model is devised to support purchase decisions where users can make timely actions on how much to order and when to buy raw materials. Also, optimal time lag, which minimizes the storage time for pre-assembled materials, is obtained. To verify this method, a real case is applied to elicit an optimal amount of inventory and time lag. It is found that average values as well as variability of inventory level decreased significantly so as to minimize economic costs related to inventory management under uncertain project condition.

• Journal of Distribution Science
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• v.13 no.7
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• pp.63-71
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• 2015

Purpose - The characteristics of the modern management environment in Korea clearly involve the limitations of knowledge management, globalization, changes in industrial structures, polarization of the economy, consumption, and education, and the demand for creative management. To achieve a continuous competitive advantage for individuals as well as organizations, Wisdom Management can be said to be a paradigm for the current environment. The Research is an alternative to environmental management in the early study of the need to conceptualize the theoretical approach to wisdom management. In other words, it presents a new management paradigm for a business environment of uncertainty and unpredictability. Furthermore, it aims to propose Wisdom Management as an alternative in the modern management environment as well as a topic of discourse. Its purpose is to provide basic knowledge to people who study and practice in this field to strengthen the competitiveness of individuals and companies. Research design, data, and methodology - This paper first provides six characteristics of the current management environment at home and abroad. It then attempts to emphasize the necessity of wisdom based on such characteristics by classifying wisdom according to recent management study research. This allows the derivation of definitions of wisdom management, suggesting its components and properties. Results - The six characteristics of the modern business environment are: 1) limits of knowledge, 2) intensifying globalized competition, 3) changes in industry structure - IoT (Internet of all Things) trend, 4) serious polarization and social unrest diffusion, 5) personal and organizational competitiveness creativity requirements, and 6) domestic special national and social situations. Therefore, accordingly, wisdom can be defined and classified as: wisdom that offers potential integration beyond knowledge, practicing and maintaining knowledge wisdom as an efficient strategy for an organization wisdom as a decision-making process that addresses ambivalence wisdom as the pursuit of common goods based on ethics; and, wisdom as creativity that involves intuition and insight. This paper attempts to define Wisdom Management in accordance with these definitions of wisdom. Wisdom Management is a management system that is awareof the current environment given in the multidimensional perspective, achieves the efficiency of the organization and the goals of common good through an uncertain decision-making process, based on the organization of individual and organizational knowledge, and the internal experiences and resources. Wisdom Management components include human beings, virtue, knowledge, creativity, and ambivalent thinking. Its properties include intentionality, self-destructiveness, creative and ethical reflexivity, complexity, insight, unpredictability, ambivalence, and wholeness. Conclusions - Since all organizations face the limitations of their environment, crises, and opportunities, applying wisdom in management to develop as Wisdom Management can be an inevitable alternative to the uncertainties of the management environment faced by modern society. The conceptualization of Wisdom Management forms a valuable context to further advance knowledge management theory into practice. It is also a cornerstone of strategic management and can provide insight into its potential for success and implementation.

• Trans-
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• v.3
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• pp.29-53
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• 2017

The film scholar Vincent Amiel divides into three types of montage through his book The Aesthetics of Montage ; Montage narratif, Montage discursif, and Montage decorrespondances. These three categories are the concept that encompasses the aesthetic class to which most movies belong. Early films pursued the essential and basic functions of editing, which tend to be modified in the direction of enhancing the director's goals over time. In this way, "Expressive Montage" is one of most important concepts of montage, not as a 'methodology' that combines narrative but as a 'purpose'. In the montage stage, the expressive montage work is done through three steps of decision. The process of 'combining' to combine the selected films in a certain order, after the process of 'selection' which selects only necessary parts of the rush film, and 'connection' to determine the scene connection considering the duration of the shot. The connection is the final stage of the montage. There are exceptions, of course. When fiction films of classical narratives use close-ups, or when using models or objects of neutered animals, the film induces the tendency of a "montage decorrespondances" rather than a "montage narratif" or "montage discursif". This study attempts to analyze the tendency of montage of works with 'uncertain connection' through 'collage' used by close-ups and montage decorrespondances as 'fragmentation tendency of modern films'. The fragmentation of the montage in contemporary film breaks the continuous and structural nature of the film, and confuses the narration structure that is visible on the surface of the film. The tendency of the fragmentation of the montage, which started from this close-up, seems to give an answer to the extensibility of the modern image.

• Korean Journal of Social Welfare Studies
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• v.44 no.3
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• pp.207-236
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• 2013

This article aims to understand the process of effective leadership in the Community Care Centers for the Disabled(CCCD). Using a qualitative approach and the concept of 'Sensemaking', a term introduced by Weick (1995), I described and explored the process of leadership. Sensemaking enables leaders to have a better grasp of what is going on in their environments. Sensemaking theory offers a perspective on leadership that resolves successfully complex situations surrounding the CCCD. The CCCDs face the environmental changes such as a paradigm shift of disability and a rivalry system with private services. In this time of uncertain change, the CCCDs are in need of leadership of the executives who could reduce complexity with shared meaning. Data were collected over 5 weeks from the 6 CCCDs, through semi-structured interviews, with practitioners, middle managers and chief executives. The interview scripts were thematically analyzed through Atlas-ti programme. The findings showed three subjects, the people's perception of environment, organizational visioning and interactions among post positions. Even though the 6 CCCDs were under the same environment, the perceptions and the enactments of the practitioners were influenced by the chief executives' sensemaking. The important factors of the chief executives' sensemaking were the daily interaction as well as ongoing reflection on their experiences.