• Journal of Information Technology Application
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• v.3 no.2
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• pp.67-82
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• 2001

The ILOF project addresses the needs of logistics industrial organizations to reduce information processing time, improve added and residual value of information and reduce processing and transportation costs. It deals with the information supply chain information systems shared by vertical partner as important entity, whose performance and optimization very significantly affects the efficiency and performance of logistics industries. This paper deals with logistics information exchange systems based on supply chain management, focusing on sharing database and processes between partners such as shipper, logistics broker, transportation company, shipping company etc., for smoothing the information flow, enhancing consumer service and reducing communication fee and labour costs. The significance of contribution of this research is the provision of a model for logistics information exchange including entity relationship diagram, data flow diagram and functions which is able to facilitate the formulation of a customer driven supply chain information network, there by enhancing the competitive edge of companies in logistics industries on local and global basis.

• Communications for Statistical Applications and Methods
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• v.30 no.2
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• pp.163-178
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• 2023

GARCH-X(1, 1) model specifies that conditional variance follows an AR(1) process and includes a past exogenous variable. This study proposes a new class from that model by allowing a more general (non-linear) variance function to follow an AR(1) process. The functions applied to the variance equation include exponential, Tukey's ladder, and Yeo-Johnson transformations. In the framework of normal and student-t distributions for return errors, the empirical analysis focuses on two stock indices data in developed countries (FTSE100 and SP500) over the daily period from January 2000 to December 2020. This study uses 10-minute realized volatility as the exogenous component. The parameters of considered models are estimated using the adaptive random walk metropolis method in the Monte Carlo Markov chain algorithm and implemented in the Matlab program. The 95% highest posterior density intervals show that the three transformations are significant for the GARCHX(1, 1) model. In general, based on the Akaike information criterion, the GARCH-X(1, 1) model that has return errors with student-t distribution and variance transformed by Tukey's ladder function provides the best data fit. In forecasting value-at-risk with the 95% confidence level, the Christoffersen's independence test suggest that non-linear models is the most suitable for modeling return data, especially model with the Tukey's ladder transformation.

• YAKHAK HOEJI
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• v.32 no.1
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• pp.86-94
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• 1988

Some rheological properties of subfractions for dextran in the molecular weights range from $3{\times}10^4$ to $2{\times}10^6$ was investigated at room temperature. The dependence of the viscosity on concentration, shear rate, pH & ionic strength, temperature and solvent effect was observed. From the experimental data the Mark-Houwink viscosity equation in water at $25^{\circ}C$ was determined for samples having the molecular weight ranging from $3{\times}10^4$ to $2{\times}10^6$ as$[{\eta}]=3.1{\times}10^{-3}\;Mw^{0.39}(in\;dl/g)$. The intrinsic stiffness of the dextran backbone was estimated by evaluating the 'characteristic ratio' $C_{\infty}$, which is below the 0.082. In the concentrated region, the viscosity was decreased with increasing shear rate and was exponentially decreased with raising temperature, the viscosity showed the maximum value at neutral condition. From the experimental data, it was concluded that dextran chain, linked by the ${\alpha}-1$, 6-glucosidic linkage, behaves like a flexible random coil chain in aqueous solution, dextran solutions were pseudoplastic power law fluids among the empirical models of non-Newtonian behavior. Urea was an active reagent which increases the viscosity and swells dextran while pyrididine and glycerol were inactive reagents. Also, it could be estimated that the formation of gel structure is promote to the neutral state, the molecular weight larger than $2{\times}10^5$, when electrolytic concentration is IN and Ureas is use to solvent.

• Journal of Information Technology Applications and Management
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• v.31 no.2
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• pp.51-66
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• 2024

Internet of Things (IoT) is a term that has been introduced in recent years, and it defines objects being able to connect and transfer data through the internet. Although some IoT-related products are currently available in the market, there are still some IoT problems that need to be overcome, such as the technology issues and lack of confidence and understanding of IoT. This study aims to analyze the influential factors in building successful IoT system for smart supply chain. This study develops the Analytic Hierarchy Process (AHP) to evaluate the influential factors in IoT. This study finds that tangible factors (Technology, Value and Connectivity) are more important than the intangible factors (Operation and Intelligence). Finally, this study concludes that after enterprises build a good IoT connectivity system, it is essential to combine this with good IoT technology to create a successful IoT environment. The findings may help practitioners implement IoT in smart supply chains to deal with disruptions, risks and vulnerabilities in the post-pandemic era.

• Journal of Korea Trade
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• v.23 no.3
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• pp.1-19
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• 2019

Purpose - This research examines the effect of a foreign subsidiary on the productivity growth of a Two-way trading manufacturing firm in Korea. We explore firms engaged in both trade and FDI simultaneously to verify whether participation in GVC as a broad concept is an efficient internationalization strategy to increase the productivity of a Korean manufacturing firm. Design/methodology - Based on the firm-level data by utilizing the Survey of Business Activities from Statistics Korea, we examine the impact of vertically integrated foreign subsidiaries on the productivity of a manufacturing firm that exports and imports simultaneously. Findings - The results show that if a Two-way trading firm establishes one or more overseas subsidiaries, the total factor productivity growth increases. Moreover, the FDI effect is statistically significant when the destination country has an economically close relationship with Korea. However, these effects are disparate depending on the industrial competitiveness or market situation where the subsidiary is located. Nonetheless, the synergy effect resulting from industrial combination is represented in China and the USA only. Originality/value - As the importance of GVC has become more emphasized around the world. In spite of the scarcity of related domestic studies, we explored the effect of multinational manufacturing firms participating in GVC using firm-level data.

• Journal of Korea Trade
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• v.26 no.6
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• pp.96-117
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• 2022

Purpose - Considering the recent instability of world economy and its heavy dependence on foreign, Korea must formulate breakthrough approaches to proactively cope with these adverse global developments. As such, this study aims to ascertain how participation in global value chains (GVCs) relates to corporate productivity and derive policy implications. Design/methodology - This study utilizes the microdata of Korean manufacturers to develop indicators of GVC participation at the enterprise level and analyzes the effects of GVC participation on the firm's total factor productivity by using fixed effect model. Findings - Enterprises with highest rates of export-side GVC participation see their productivity grow as their export-side GVC participation rates increase. In addition, when companies are classified by their export-side GVC participation rates, increasing export values improves all firm's productivity. In particular, those with low participation rates are analyzed to achieve higher productivity by increasing their imports, not only exports, which implies that companies with lower export-side GVC participation can boost productivity by reinforcing their export and import activities. Originality/value - This research paper distinguishes itself from others in that it makes a novel attempt to design the indicators of GVC participation at the enterprise level, not at the national or industry level. In addition, this study contributes to the existing literature by dividing companies into subgroups depending on their GVC participation rates for each of export and import and identifying variances in the effect of GVC participation on productivity growth among subgroups.

• The Journal of the Korea Contents Association
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• v.16 no.3
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• pp.667-675
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• 2016

The aim of this study is to predict use behavior for social welfare service of the elderly mentally ill through means-end chain theory. Means-end chain theory explains cognitive structure related to the consumer's preference to various products and services. Although the elderly mentally ill begin to emerge as new client population, social welfare services for them do not seem to be enough in the community. Based on this awareness, this study tried to analyse service use behavior of the elderly mentally ill through means-end chain theory to develop new social welfare services. The data were collected from 15 elderly mentally ill and found 5 attributes, 10 consequences, and 11 values. Hierarchical Value Map was composed of 'disease management, rehabilitation preparation, hobby leisure ${\rightarrow}$ health maintenance, energy of life ${\rightarrow}$ social reintegration, life satisfaction, harmonious family life'. To activate the social service for the elderly mentally ill, it should be developed various programs such as disease management, rehabilitation preparation, hobby leisure for the elderly mentally ill. The ultimate value of these programs will be improve life satisfaction and integrated into society.

• Journal of the Korean Institute of Landscape Architecture
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• v.47 no.2
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• pp.88-99
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• 2019

This study aims to conduct a depth analysis of motivation and value of local residents and tourists based on means-end chain theory. The sampling of the study was conducted on local residents living near downtown area of Gyeong-ju City, and tourists through soft laddering and hard laddering methods. A mutual correlation model in relation with Hierarchical Value Map (HVM) for each group by conducting the analysis of factor loading (attributes, consequences, value) and cognitive structure (the correlations among attributes, consequences and value) was proposed and the comparisons of HVM for each group was also conducted. The structured questionnaires using Association Pattern Technique (APT) of hard laddering were utilized to analyze the means and end of value chain structures in terms of the attributes, consequences, value of Gyeong-ju Ancient Tombs. The findings propose that local residents are visiting Ancient Tombs Gyeong-ju City Center for 'Rest and take a walk' as the means, which results in 'Relieving stress' and eventually leads to the 'Improvement of historic and cultural cultivation' as the end. On the other hand, tourists also 'Rest and take a walk' as the mean, which also leads to 'Relieving stress'. However, unlike local residents, it eventually leads to 'Self-reflection and healing' as the end. It is expected that the findings of this study not only recommend us to consider preserving and managing cultural heritages and value of ancient tombs in developing "Ancient Tomb Park in Gyoneg-ju City Center" but also provides baseline data for the establishment of reasonable plans of utilizing tombs, historical and cultural heritages.

• The Journal of the Korea Contents Association
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• v.21 no.2
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• pp.121-129
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• 2021

In this study, we try to minimize the tariff risk by constructing a hazardous cargo screening model by applying Association Rule Mining, one of the data mining techniques. For this, the risk level between supply chains is calculated using the Apriori Algorithm, which is an association analysis algorithm, using the big data of the import declaration form of the Korea Customs Service(KCS). We perform data preprocessing and association rule mining to generate a model to be used in screening the supply chain. In the preprocessing process, we extract the attributes required for rule generation from the import declaration data after the error removing process. Then, we generate the rules by using the extracted attributes as inputs to the Apriori algorithm. The generated association rule model is loaded in the KCS screening system. When the import declaration which should be checked is received, the screening system refers to the model and returns the confidence value based on the supply chain information on the import declaration data. The result will be used to determine whether to check the import case. The 5-fold cross-validation of 16.6% precision and 33.8% recall showed that import declaration data for 2 years and 6 months were divided into learning data and test data. This is a result that is about 3.4 times higher in precision and 1.5 times higher in recall than frequency-based methods. This confirms that the proposed method is an effective way to reduce tariff risks.

• Journal of Distribution Science
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• v.12 no.4
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• pp.47-54
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• 2014

Purpose - The postponement strategy, which delays the form, place, and production of products as late as possible, has been widely considered as a competitive supply chain management scheme in an era of mass customization and modular manufacturing. An interesting business phenomenon is that not all manufacturing/logistics firms choose the postponement strategy. Given that postponement is a counter-measure to speculation, which has some advantages under certain environments, the current imprudent inclination toward the postponement strategy may cause firms to lose the potential of the speculation strategy, an alternative strategy in supply chain management. Building on the logistics and manufacturing literature, this study examines characteristics of two contrasting strategies, postponement and speculation, and major factors favoring each strategy. Research design, data, and methodology - We apply the profiling approach to two business cases, HP printer and LG mobile phone. The profiling approach is a method of choosing a particular strategy aligned with environmental factors. While various approaches have been used to check the fit between a business strategy and environmental factors, the literature on manufacturing strategy and logistics has commonly adopted the profiling approach. Major factors used in profiling variables are derived from the literature. Two samples, HP printer and LG mobile phone, are selected, because they represent major characteristics appropriate for each strategy. The profiling is based on data from semi-organized interviews with managers. Results - The profiling approach shows that the postponement strategy is a suitable one for HP printers. Most factors, such as product life cycle, large production volume, low-price, product value, and monetary density, support delaying end products until as late as possible. Despite some exceptions, such as delivery time and economy of scale, our analysis states that the overall profile of HP printer is favorable for the postponement strategy. On the other hand, LG mobile phone may adapt the speculation strategy. Although it has large production volume and low delivery frequency, most characteristics support the speculation strategy for this product. An interesting finding is that, despite common perception that advanced technology products such as mobile telephones favor the postponement strategy, profiling proposes the speculation strategy for this product. Conclusions - Our analysis shows that speculation is not the universal option for supply chain management, and that, when choosing a specific strategy, one should consider many factors simultaneously. A major implication of our work is to emphasize the role of environmental factors such as supply chain variables in choosing an inventory strategy, and the importance of fit rather than solely strategic orientation. A theoretical contribution is to demonstrate the benefit of the simultaneous consideration of business variables in choosing specific strategies. For practitioners, our work leads us to consider the existence and the potential of speculation as a counter-measure to postponement. In addition, the comprehensive framework in this research may be instantly used in examining a practical strategy.