• Proceedings of the KAIS Fall Conference
• /
• 2003.11a
• /
• pp.141-148
• /
• 2003

Customer retention is a common concern for many industries and a critical issue for the survival in today's greatly compressed marketplace. Current customer retention models only focus on detection of potential defectors based on the likelihood of defection by using demographic and customer profile information. In this paper, we propose a dynamic procedure for defection detection and prevention using past and current customer behavior by utilizing SOM and Markov chain. The basic idea originates from the observation that a customer has a tendency to change his behavior (i.e. trim-out his usage volumes) before his eventual withdrawal. This gradual pulling out process offers the company the opportunity to detect the defection signals. With this approach, we have two significant benefits compared with existing defection detection studies. First, our procedure can predict when the potential defectors could withdraw and this feature helps to give marketing managers ample lead-time for preparing defection prevention plans. The second benefit is that our approach can provide a procedure for not only defection detection but also defection prevention, which could suggest the desirable behavior state for the next period so as to lower the likelihood of defection. We applied our dynamic procedure for defection detection and prevention to the online gaming industry. Our suggested procedure could predict potential defectors without deterioration of prediction accuracy compared to that of the MLP neural network and DT.

• Bulletin of the Korean Chemical Society
• /
• v.19 no.9
• /
• pp.962-967
• /
• 1998

Block copolymers consisting of poly(rbenzyl L-glutamate) (PBLG) as the hydrophobic part and poly(ethylene oxide) (PEO) as the hydrophilic part were synthesized and characterized. Polymeric micelles of the block copolymers (abbreviated GEG) were prepared by a dialysis method. The GEG block copolymers were associated in water to form polymeric micelles, and the critical micelle concentration (CMC) values of the block copolymers decreased with increasing PBLG chain length in the block copolymers. Transmission electron microscopy (TEM) observations revealed polymeric micelles of spherical shapes. From dynamic light scattering (DLS) study, sizes of polymeric micelles of GEG-1, GEG-2, and GEG-3 copolymer were 106.5±59.2 nm, 79.4±46.0 nm, and 37.9±13.3 nm, respectively. The drug loading contents of GEG-1, GEG-2 and GEG-3 polymeric micelles were 12.6, 11.9, and 11.0 wt %, respectively. These results indicated that the drugloading contents were dependent on PBLG chain length in the copolymer; the longer the PBLG chain length, the more the drug-loading contents. Release of norfloxacin (NFX) from the nanoparticles was slower in higher loading contents of NFX than in lower loading contents due to the hydrophobic interaction between PBLG core and NFX.

• Journal of Distribution Science
• /
• v.22 no.1
• /
• pp.105-113
• /
• 2024

Purpose: This study sheds light on the need for trust in buyer-seller relationships in supply chains and explores why long-term orientation is important. It also investigates the effect on relationship performance. This study provides implication on how to build robust supply chains. Methodology: A survey was conducted with firms with supply chains in South Korea. A total of 350 valid questionnaires were analyzed through Entrust Survey-a sampling company. Structural equation modeling (SPSS 18.0 and AMOS) was employed to test the hypotheses. Results: Cognitive trust had a positive effect on emotional trust. Emotional trust had a positive effect on long-term orientation but did not have a significant effect on relationship performance. Long-term orientation was proportionate to relationship performance. Conclusions: Trust is a critical factor in supply chains. As business environments are rapidly changing, the uncertainties are also meaningful. Supply chains have collapsed owing to COVID-19, the Russia-Ukraine war, and the U.S.-China trade war, and they are only just recently being rebuilt. Maintaining relationships with supply-chain partners is vital, and promoting cognitive and emotional trust is necessary.

• BMB Reports
• /
• v.48 no.1
• /
• pp.48-53
• /
• 2015

Oxidized LDL (oxLDL) performs critical roles in atherosclerosis by inducing macrophage foam cell formation and promoting inflammation. There have been reports showing that oxLDL modulates macrophage cytoskeletal functions for oxLDL uptake and trapping, however, the precise mechanism has not been clearly elucidated. Our study examined the effect of oxLDL on non-muscle myosin heavy chain IIA (MHC-IIA) in macrophages. We demonstrated that oxLDL induces phosphorylation of MHC-IIA (Ser1917) in peritoneal macrophages from wild-type mice and THP-1, a human monocytic cell line, but not in macrophages deficient for CD36, a scavenger receptor for oxLDL. Protein kinase C (PKC) inhibitor-treated macrophages did not undergo the oxLDL-induced MHC-IIA phosphorylation. Our immunoprecipitation revealed that oxLDL increased physical association between PKC and MHC-IIA, supporting the role of PKC in this process. We conclude that oxLDL via CD36 induces PKC-mediated MHC-IIA (Ser1917) phosphorylation and this may affect oxLDL-induced functions of macrophages involved in atherosclerosis.

• International Commerce and Information Review
• /
• v.1 no.1
• /
• pp.25-39
• /
• 2008

Global e-SCM (electronic Supply Chain Management) has become an important business strategy in a rapidly changing global competition environment. It encompasses both domestic business and overseas business. Overseas business, including B2B and B2G, involves the complex trade procedures across countries. So, the standardization of electronic documents (messages) and business processes is one of critical factors for the successful implementation of global e-SCM. Without standardized messages and streamlined business processes, the benefits of global e-SCM would not be guaranteed because of human intervention like re-keying business data, which may create errors, delay processes, cause additional data or procedures, etc. Thus, this paper is to review the implementation challenges of Global e-SCM, to address the needs for electronic information flows through the standardization in electronic documents and business processes for fast and accurate trade transactions in the global supply chain activities, and to assert the importance of adoption of international standards.

• Journal of the Korean Operations Research and Management Science Society
• /
• v.41 no.1
• /
• pp.21-39
• /
• 2016

Although the demand for IT outsourcing (ITO) has increased recently because of the recent recession, concerns about business discontinuity in the transition phase cause companies to hesitate to adopt ITO. Therefore, a guideline to improve the prospects is needed. However, studies on the success factors of the transition phase in ITO are lacking. In this study, we develop an expert hierarchical value map (HVM) of the success of the transition phase in ITO by using cognition scientific methodologies. We empirically verify how success factors affect the success of the transition phase. Specifically, we derive an HVM of main stakeholders by using in-depth interviews and approaches, such as repertory grid technique (RGT) and laddering, based on means-end chain theory. We validate the success factors empirically through a bipolar analysis of RGT. Finally, we determine the most important cluster of success factors through cluster analysis.

• Proceeding of EDISON Challenge
• /
• 2015.03a
• /
• pp.292-295
• /
• 2015

The effect of Ligand Binding energy in quantum rod (CdS/ZnS) plays a critical role in anisotropic growth. As mimicking large chain of ligands and using the head of the chain, I plan to bind the quantum rod and ligands so that it can grow well consequently. So the ultimate goal of this study is on how ligand binding can affect the growth of this quantum rod. There are preferred surfaces between the quantum rod and ligands, and we empirically know that ligands which bind the quantum rod; Phosphoric oxide (PO), Phosphoric acid(PA), Carboxylic acid(CA), Trimethylamine(TMA), have strong tendency to be attached on the surfaces of CdS/ZnS; ($11{\bar{2}}0$), ($10{\bar{1}}0$), ($000{\bar{1}}$), (0001). I virtually bond the surface and the ligands, and calculated the ligand binding energy after optimizing their structure, utilizing EDISON simulator. After all, I figured out how they are linked each other and how the quantum rod grows.

• Journal of the Korean Applied Science and Technology
• /
• v.9 no.1
• /
• pp.1-6
• /
• 1992

New five N-acyl-N-methyl taurate and their sodium salts were synthesized by acylating sodium N-methyl taurate in water in the presense of inorganic alkali as a catalyst. Wherein acyl group is a straight-chain radical of 10 to 18 carbon atoms. These compounds were identified by infrared spectroscopy. Surface activities of these sodium N-acyl-N-methyl taurate including surface tension, Ross-Miles foaming powers, foam stabilities, emulsifying powers and detergency were measured respectively. Also critical micelle concentration(cmc) were evaluated. Consequently these anionic surfactants with long chain acyl amine showed good emulsifying power of O/W type and had a good detergence.

• Proceedings of the Korea Association of Information Systems Conference
• /
• 2005.12a
• /
• pp.381-387
• /
• 2005

As the most widely used media of BtoB e-business, the e-Marketplace (EM) can play an important role in the age of c-commerce (collaborative commerce). In supply chain management (SCM) area, the relationship-based collaboration among partners has shown great efficiency. Although the collaboration is important in both areas of EM and SCM there has been a critical difference in the selection of trade partners between them. In this paper, the EM's collaborative stages for integration with its customer system are reviewed and a system architecture is proposed for EM's electronic functional role within the perspective of collaborative commerce and buyer-supplier relationship. The relationship-based BtoB commerce through EM is reviewed to explain that it can be more beneficial than the commerce based on the price competitive selection of trade partners. With the proposed system architecture, an EM can be the functional medium for the collaborative IOIS system architecture.

• Journal of Korean Institute of Industrial Engineers
• /
• v.26 no.4
• /
• pp.384-391
• /
• 2000

Most of the previous works on classical location models are based on the assumption that the value(or utilities) of inventory remains constants over time. In this study a special case of location problem is studied for both ameliorating and deteriorating items in two-echelon supply-chain management such as agricultural and fishery products. The objective of this study is to determine the minimum number of storage facilities among a discrete set of location sites so that the probability for each customer to be covered is not less than a critical value. We have formulated this problem using stochastic set-covering problem which can be solved by 0-1 programming method. Also we developed a computer program and applied to a set of problems for fish culture storage and distribution centers and the sample results well show the impact of ameliorating and deteriorating rate on the location problem. For the further study, a graphical user-interface with visualization for input and output is needed to be developed.