• Transactions of the Korean Society of Mechanical Engineers B
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• v.29 no.1 s.232
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• pp.123-130
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• 2005

A digital in-line holographic particle image velocimetry (HPIV) which can be applied to measure three-dimensional velocity fields of turbulent flows was developed. There are three different implementation methods of HPIV: traditional film-based HPIV, intermediate HPIV and digital HPIV. The traditional film-based HPIV and intermediate HPIV method is rather troublesome to do experiments and takes long calculation time, compared with the digital HPIV, Configuration of the digital in-line HPIV is simple and the data processing routine is similar to conventional 2D PIV methods. The digital HPIV velocity field measurement consists of four steps: recording, numerical reconstruction, particle extraction and velocity extraction. In the velocity extraction process, we improved PTV algorithm to extract the displacement of particle each placed in 3D space. The developed digital in-line HPIV system was applied to a vertical jet flow. The 3D velocity vectors measured by the digital HPIV method in the near field are in a good agreement with 2D PIV results.

• Elastomers and Composites
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• v.51 no.4
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• pp.301-307
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• 2016

Additive manufacturing (AM), so called 3D Printing is a new manufacturing process and is getting attraction from many industries. There are several methods of 3D printing. Among them fused deposition modeling (FDM) type is most widely used by reason of cheap maintenance, easy operation and variety of polymeric materials. Articles manufactured by 3D printing have weak deposition strength compared with conventionally manufactured products. Deposition strength of FDM type 3D printed article is highly dependent of deposition temperature. Subsequently the nozzle temperature in the FDM type 3D printing is very important and it is controlled by heat source in the 3D printer. Nozzle is connected with heat block and barrel, and heat block contains heat source. Nozzle becomes hot through heat conduction from heat source. Nozzle temperature has been predicted for various thermal boundary conditions by computer simulation and compared with experimental measurement. Nozzle temperature highly depends upon thermal conductivities of heat block and nozzle. Simulation results are good agreement with experiment.

• Journal of the Korean Operations Research and Management Science Society
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• v.28 no.2
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• pp.17-33
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• 2003

The explosive growth of the internet-based transactions requires not only a secure payment system but also an appropriate trust measuring methodology and secure transaction protocols to guarantee the minimal risk for the transacting entities involved in specific transactions. Especially, in internet auction systems where either buyers or sellers or both can be more than one in one transaction, providing those systems that make sure no one transacting entity takes a major risk becomes critical. In this paper, an improved trust measuring method using a relationship-based internet community for an auction system is proposed. The proposed system incorporates fuzzy set and calculation concepts to help build trust matrices and models, which is used to measure the level of risk involved in a specific auction trade concerned. Also, to optimize the auction trade process in terms of cost and time, the proposed system recommends a differentiated trade protocol according to the risk level involved in each auction trade. To test the appropriateness of the proposed trusted auction system, a prototype system has been developed under a Windows-NT environment.

• Korean Management Science Review
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• v.21 no.2
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• pp.145-165
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• 2004

Frequently. lots of organizations have experienced the value discrepancy between the expected value and the realized value from IS (information systems) investments. Being positive or negative the difference is. however, the existence of discrepancy itself is an evidence of less-than-sound management and measurement of IS projects. Analyzing the factors that cause such discrepancy has become an issue of scrutiny both in academia and in practice. We model which factors. as predictors, will affect the value discrepancy, as dependent variables. in IS investment. This research will establish and examine the research model. the validity of category classification of value discrepancy factors and the perceptual level of IS value discrepancy by survey research. As a result of the survey research. the strategic alignment. the proper system design for staffs. the project planning capability. and interdepartmental task cooperation are perceived as the factors that significantly affect the value discrepancy. And known as IS success factors such as the managerial support, the change management, the standardized process. and the competitive investment are not significant factors. The research findings will provide and emphasize useful implications which factors should be deliberately investigated in IS investment both for practices considering IS deployment and for academia.

• International Journal of Automotive Technology
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• v.6 no.3
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• pp.259-268
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• 2005

In order to analyze the sheet drawability, the measurement of the plastic strain ratio was carried out for the 5182 aluminum alloy sheets in which were cold rolled without lubrication and subsequent recrystallization annealing. The average plastic strain ratio of the 5182 aluminum sheets was 1.50. It was considered that the higher plastic strain ratio was resulted from the ND//<111> component evolved during rolling and maintained during annealing. The AA5182/polypropylene/AA5182 (AA/PP/AA) sandwich sheets of the 5182 aluminum alloy skin sheet and the polypropylene core sheet with high formability have been developed for application for automotive body panels in future light weight vehicles with significant weight reduction. The AA/PP/AA sandwich sheets were fabricated by the adhesion of the core sheet and the upper and lower skin sheets. The AA/PP/AA sandwich sheet had high plastic strain ratio (1.58), however, the planar anisotropy of the sandwich sheet was little changed after fabrication. The optimum combination of directionality of the upper and lower skin sheets having high plastic strain ratio and low planar anisotropy was calculated theoretically and an advanced process for producing the sandwich sheets with high plastic strain ratio was proposed. The developed sandwich sheets have a high average plastic strain ratio of 1.55 and a low planar anisotropy of 0.17, which was improved more by 3.2 times than that of 5182 aluminum single sheet.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.10
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• pp.171-182
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• 2020

This research focuses on the importance of corporate social responsibility in building the company's reputation. Experts have studied CSR as an antecedent of a company's reputation, but the mechanisms underlying this process are rarely explored. Therefore, to fill this research gap, we demonstrate CSR's implementation combined with organizational justice based on discrepancy and equity theory. This study involved 210 employees in a family company. The study's analysis method uses Structural Equation Model (SEM), SmartPLS, with a five-step measurement and analysis procedure. The variables in this study are CSR implementation, organizational justice, employee trust, firm reputation, organizational objectiveness, organizational commitment, job satisfaction, and job performance. The results found that some of the direct relationships stated were not significant, but all demonstrations of indirect links were substantial. Besides, optimal CSR and organizational justice provide a reliable and positive domino effect in increasing the role and consequences of employee trust and firm reputation. The findings in this study confirm that upstream-downstream job performance causality can be successfully achieved if job satisfaction has been realized, job satisfaction can be achieved if organizational commitment can also be recognized, and organizational commitment can be developed. Reflection and influence, rather than organizational attractiveness becomes essential.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.10
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• pp.707-716
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• 2020

The study investigates the relationship between broad-scope management accounting information usage, market orientation, and the firm performance. This study employs a survey data of 149 top-level and mid-level managers working in Vietnamese tourism enterprises. To analyze research data, we employ SmartPLS 3 software. The analytical process include measurement model evaluation (evaluate the scale's validity and reliability) and structural model evaluation (test research hypotheses). The results reveal that broad-scope management accounting information usage has a positive direct effect on market orientation dimensions (include information generation, information dissemination, and responsiveness). Then, market orientation dimensions also have positive direct effects on the performance of Vietnamese tourism firms, excluding information dissemination. Moreover, this study also reveals that the market orientation dimensions mediate the relationship between broad-scope management accounting information usage and firm performance. The findings of this study suggest that tourism firms should pay more attention to the use of management accounting information in decision-making. With the increasingly fierce competition of the tourism firms today, capturing and meeting the needs of the market is a prerequisite to help firms enhance their competitiveness and improve their performance. To do that, Vietnamese tourism firms need to consider pursuing market orientation and enhancing broad-scope management accounting information usage.

• Journal of the Korean Institute of Intelligent Systems
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• v.15 no.4
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• pp.443-450
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• 2005

In this paper, we propose an intelligent model lot extraction of the web user's preference and present the results of evaluation. For this purpose, we analyze shortcomings of current information retrieval engine being used and reflect preference weights on learner. As it doesn't depend on frequency of each word but intelligently learns patterns of user behavior, the mechanism Provides the appropriate set of results about user's questions. Then, we propose the concept of preference trend and its considerations and present an algorithm for extracting preference with examples. Also, we design an intelligent model for extraction of behavior patterns and propose HTML index and process of intelligent learning for preference decision. Finally, we validate the proposed model by comparing estimated results(after applying the Preference) of document ranking measurement.

• Proceedings of the Safety Management and Science Conference
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• 2005.05a
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• pp.273-278
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• 2005

Prescribed according to the occupational safety and health low noise measurement method was changed to personal sampling in the method to measure an area noise. Such method had the limit which did not evaluated characteristic of sound of occurrence and the place of origin. This study was performed to establish an engineering remedy of the work-place noise. The subject was a vibration control process of the place of business in Pusan. A simulation program applied for an engineering improvement of the work-place noise. The results were as follows: 1. An noise occurrence level of the work-place before improvement was $88^{\sim}97dB(A)$, We applied an improvement method to be established and were expected to $80^{\sim}119dB(A)$. 2. The level of the noise-distribution to appear in the place of origin of the work-place before improvement was $90^{\sim}93dB(A)$ but, We executed the simulation after applied an engineering remedy and predicted $80^{\sim}85dB(A)$. A result of the simulation blue part was changed mostly into the dark blue color. The results suggest that simulation program establishes an engineering remedy and is useful to the case to apply.

• Proceedings of the Safety Management and Science Conference
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• 2004.05a
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• pp.247-257
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• 2004

Electrodes were fabricated based on activated carbon powder BP-20, conducting agent such as Super P, vapor grown carbon fiber (VGCF) and acetylene black (AB), and the mixed binders of flexible poly(vinylidenefluoridehexafluoropropylene) [P(VdF-co-HFP)] and cross linking dispersion agent of polyvinylpyrrolidone (PVP) to increase mechanical strength. According to impedance measurement of the electrode with the addition of conducting agent, we found that it was possible to charge rapidly by the fast steady-state current convergence due to low equivalent series resistance (AC-ESR, fast charge transfer rate at interface between electrode and electrolyte and low RC time constant. The self-discharge of unit cell showed that diffusion process was controlled by the ion concentration difference of initial electrolyte due to the characteristics of Electric Double Layer Capacitor (EDLC) charged by ion adsorption in the beginning, but this by current leakage through the double-layer at the electrode/electrolyte interface had a minor effect and voltages of curves were remained constant regardless of electrode material. We found that the 2.3V/230F grade EDLC would be applied to industrial safety usage such as uninterrupted power supply (UPS) because of the constant DC-ESR by IR drop regardless of discharge current.