• Korean Journal of Materials Research
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• v.19 no.3
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• pp.156-162
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• 2009

Lubricant-based nanofluids were prepared by dispersing carbon nanoparticles in gear oil. In this study, the effects of the particle size, shape and dispersity of the particles on the tribological properties of nanofluids were investigated. Dispersion experiments were conducted with a high-speed bead mill and an ultrasonic homogenizer, and the surfaces of the nanoparticles were simultaneously modified with several dispersants. The effective thermal conductivity of the nanofluids was measured by the transient hot-wire method, and the tribological behaviors of the nanofluids were also investigated with a disk-on-disk tribo-tester. The results of this study clearly showed that the combination of the nanoparticles, the deagglomeration process, the dispersant and the dispersion solvent is very important for the dispersity and tribological properties of nanofluids. Lubricant-based nanofluids showed relatively low thermal conductivity enhancement, but they were highly effective in decreasing the frictional heat that was generated. For nanofluids containing 0.1vol.% graphite particles in an oil lubricant, The friction coefficient in the boundary and fluid lubrication range was reduced to approximately 70% of the original value of pure lubricant.

• Asia pacific journal of information systems
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• v.16 no.3
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• pp.29-47
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• 2006

Many companies have been implementing Enterprise resource planning (ERP) systems for their organizational transformation in order to survive and achieve strategic advantages in an increasing competitive business environment. Thus, it is meaningful to identify factors that affect ERP system operation positively. Organizational citizenship behaviors (OCB) are discretionary, extra-role behaviors of employees which go beyond the prescribed formal roles, and are known as to be the contribution factors for organization performance. The purpose of this study is to develop the measurements for the OCB constructs in ERP system context and empirically test the relationships between the OCB construct and ERP system success. The four constructs - altruism, conscientiousness and courtesy, civic virtue, and sportsmanship - and fifteen measurements on the OCB were developed based on previous studies (i.e. Organ 1988) and empirically verified by confirmatory factor analysis. The results of testing the relationships between the OCB and ERP system success show that the OCB have a significant direct impact on the information quality and intention of IT innovation while they have an indirect impact on work efficiency mediated by information quality. This study enhances the OCB model into information system arena and helps better understand the user behaviors of information systems.

• Korean Journal of Child Studies
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• v.22 no.3
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• pp.31-48
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• 2001

This study was designed to examine various patterns of developmental change in children's recall, strategic behaviors, and meta-memory with a sort-recall task in relation to utilization deficiencies. Memory tasks consisting of 18 pictures were presented individually to 48 seven-year-old children in each of 7 sessions. Sessions 1 and 2 were baseline; Sessions 3 and 4 were for strategy training, including the organization group, the self-regulation group, the organization/self-regulation group and control group. Sessions 5, 6, and 7 were unprompted tests of strategy maintenance. Results showed significant differences between the 4 groups in their recall, strategy repertories and strategy evaluation. Findings were discussed in terms of the analysis of memory strategy and memory development.

• Asia pacific journal of information systems
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• v.3 no.2
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• pp.145-168
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• 1993

It has been asserted that information technology (IT) is being exploited by a number of corporations for strategic advantage. The successful implementation of an organization-wide IT, however, not only depends on its strategic and technological feasibility, but also on the effectiveness of organizational transformation strategies. In this case, the organizational transformation strategy and its success for the adoption of computerized typesetting systems (CTS) by one of the largest Korean newspaper companies, are described With an analysis on the Korean newspaper industry, the case explains the internal and external pressure towards the introduction of the new information technology and its development process. It also provides the architecture and operational mechanism of the CTS. Finally, the case analyzes the impact of the system on the competitive behaviors of the rivals in the industry.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.55 no.5
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• pp.214-219
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• 2006

Oligopoly differs from perfect competition and monopoly in that a firm must consider rival firms' behavior to determine its own best policy. This interrelationship among firms is the issue examined in this paper. In the oligopoly market, the complete information market means that each producer has full information about itself, the market, and its rivals. That is, each producer knows the market demand function, its own cost function and the cost functions of rivals. On the other hand, the incomplete information market means that in general each producer lacks full information about the market or its rivals. Here, we assume that each firm doesn't know the cost functions and the strategic biddings of its rivals. The main purpose of this paper is to analyze firm' strategic behaviors and equilibrium in an electricity market with incomplete information. In the case study, the complete information market and the incomplete market are compared at the Nash Equilibrium from the viewpoints of market price, transaction quantities, consumer benefits, and Social Welfare.

• Journal of Information Technology Services
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• v.13 no.1
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• pp.253-267
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• 2014

This study explores to identify the characteristics of the business model by comparing and analyzing the value creation between two cases, and to be successful in business model innovation. In order for the pursuit of purposes, domestic and international firm' business model cases are analyzed. Regarding the business model innovation, huge differences are found between two cases. First, a clear customer value proposal is important. Netflix is constantly monitoring the customer's needs and satisfactions to improve value proposition, while Joycube, domestic firm does not adjust to meet the change of the customer's behaviors. Second, the business model innovation should be taking into account the customer's behaviors in the constant changing market environments. For the growth, firms should consider strategic monitoring the market environments, and find a novelty of the markets, and to create the jump through business model innovation.

• Journal of Fashion Business
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• v.4 no.4
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• pp.29-40
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• 2000

Eldery generation is a strategic purchasing consumer group in domestic fashion market for the future. The thesis of this study is that identifies needs and desires of eldery women by researching clothes purchasing behaviors and clothes selection standards. For the study, a questionnaire was used as a method of mearsurement and the eldery women in Seoul and Kyonggi were selected as a sample. Data was processed by SPSS $PC^+$ program and analyzed by using frequency, percentage, $x^2$-test and t-test. As a result of this study, clothes purchasing behaviors and clothes selection standards of eldery women can be recognized in related to age and others. A based on the results, this study is expected to assist that marketers can establish effective marketing strategy for the silver fashion business.

• Industrial Engineering and Management Systems
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• v.11 no.3
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• pp.224-232
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• 2012

The paper proposes a non-parametric methodology, data envelopment analysis, for measuring efficiency and productivity in service delivery systems with capacity constraints. The methodology provides allocation approaches for studying behaviors of firm and customers in service delivery strategy. The experimental study is carried out to investigate allocation behaviors and conduct an objective tradeoff between efficiency approach and productivity approach. The experimental result indicates that the efficiency approach allocates resource via maximizing customer efficiency rather than firm productivity as in the productivity approach. Moreover, the experiment reveals that there exists an objective tradeoff between the efficiency approach and the productivity approach. These findings provide strategic options for allocation policy in service delivery systems.

• Elastomers and Composites
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• v.58 no.3
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• pp.142-151
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• 2023

In this study, we investigate the thermal and mechanical properties of composites comprising ethylene propylene diene monomer (EPDM) and polybutadiene (PB) obtained using carbon black (CB) as a reinforcing and compatibilizing filler. Owing to the significance of elastomeric materials in various industrial applications, blending of EPDM and PB has emerged as a strategic method to optimize the material properties for specific applications. This study offers insights into the blend composition, its microstructure, and the resulting macroscopic behaviors, focusing on the synergetic effects of composite materials. Furthermore, this study delves into curing and rheological behaviors, crosslink densities, and mechanical, thermal, and elastic properties of the elastomeric composites. Through systematic exploration, we believe that this study will be beneficial to material scientists and engineers working on developing advanced elastomeric composites.

• Proceedings of the KIEE Conference
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• 2003.07a
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• pp.572-574
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• 2003

The congestion management is a key task for enhancing the effectiveness of transmission pricing mechanism in a competitive electricity market. In this paper, the zonal method of congestion management is analyzed quantitatively using equilibrium concept, and compared with the nodal pricing method. It is shown that the generation firm uses different strategies in the two methods, and the overall performance of zonal congestion management depends on the determination of zones.