• Bulletin of the Korean Mathematical Society
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• v.51 no.2
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• pp.547-553
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• 2014

The Boubaker polynomials arose from the discretization of the equations of heat transfer in pyrolysis starting from an assumed solution of the form $$\frac{1}{N}e^{\frac{A}{H/z+1}}\sum_{k=0}^{\infty}{\xi}_kJ_k(t),$$ where $J_k$ is the k-th order Bessel function of the first kind. In this paper, we investigate the distribution of zeros of the Boubaker polynomials.

• Journal of Korea Trade
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• v.25 no.4
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• pp.108-127
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• 2021

Purpose - On the basis of knowledge transfer theory, we empirically explored how three types of human resource (HR) innovation knowledge exchange within a Chaebol drive the global subsidiary performance of the headquarters (HQ) of a Chaebol's globally affiliated companies. Design/methodology - Using a sample of 176 Korean HQ firms of the top 53 Chaebols and 1,061 of their foreign manufacturing subsidiaries (n = 1,061), we tested the relationship between the exchange of explorative and exploitative sustainable HR innovation knowledge among HQ firms of Chaebols, their subsequent transfer of technical HR knowledge via technical schemas, and the subsequent impact on the global subsidiary performance. Findings - The Chaebols' decisions about the three strategic knowledge management options (i.e., the degree of exchange of explorative and exploitative technological HR innovation knowledge and the extent of HQ-subsidiary HR knowledge transfer) have highly significant relationships with the global subsidiary performance. The results help explains the conditions under which the explorative versus exchange of exploitative sustainable HR innovation knowledge pays off by showing the moderating role of the degree of HQ-to-subsidiary technical HR knowledge transfer, at least in the case of the Chaebol as one representative type of the emerging-market business groups. Originality/value - As the first of its kind in the field of sustainable HR innovation knowledge management at the business group level, the present study makes a clear contribution in demonstrating how the performance of Chaebols' manufacturing subsidiaries depends greatly on their strategy for management of knowledge, as reflected in the choices they make about sharing both explorative and exploitative sustainable HR innovation knowledge among HQ firms and the subsequent transfer of HQ's sustainable HR innovation knowledge to the foreign subsidiaries.

• Transactions on Electrical and Electronic Materials
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• v.5 no.2
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• pp.41-49
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• 2004

Layer transfer process has emerged as a promising tool in the field of thin silicon solar cell technology. This process can use mono-crystalline silicon as a surface for the epitaxial growth of a thin layer of silicon. It requires some sort of surface conditioning of the substrate due to which the surface become suitable for homo-epitaxy and lift off after solar cell fabrication. The successful reuse of substrate has been reported. The use of the conditioned surface without any kind of epitaxial layer growth is also the issue to be addressed. This review paper basically describes the five most cost effective methods on which works are in progress. Several types of possible problems envisaged by different research groups are also incorporated here with necessary discussion. Work in Korea has already started in this area in collaboration IC Design and Fabrication Centre, Jadavpur University, India and that also has been mentioned.

• Journal of Electrochemical Science and Technology
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• v.2 no.1
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• pp.20-25
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• 2011

This work focuses on the behavior of the overpotential increase due to a utilization rise in a molten carbonate fuel cell. The behavior is generally explained by Nernst loss, which is a kind of voltage loss due to the thermodynamic potential gradients in a polarization state due to the concentration distribution of reactant species through the gas flow direction. The evaluation of Nernst loss is carried out with a traditional experimental method of constant gas utilization (CU). On the other hand, overpotential due to the gas-phase mass-transport resistance at the anode and cathode shows dependence on the utilization, which can be measured using the inert gas step addition (ISA) method. Since the Nernst loss is assumed to be due to the thermodynamic reasons, the voltage loss can be calculated by the Nernst equation, referred to as a simple calculation (SC) in this work. The three values of voltage loss due to CU, ISA, and SC are compared, showing that these values rise with increases in the utilization within acceptable deviations. When we consider that the anode and cathode reactions are significantly affected by the gas-phase mass transfer, the behavior strongly implies that the voltage loss is attributable not to thermodynamic reasons, namely Nernst loss, but to the kinetic reason of mass-transfer resistance in the gas phase.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1998.06a
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• pp.57-64
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• 1998

The purpose of this research is to develop a CAD/CAM system for generation all kind of information such as, total drawing, sub assembly drawing, part drawing, detail drawing, part list, and NC data for machining by CNC lathe, Wire CUT, machining center. Through this study the CAD/CAM System for deep drawing transfer die in mechanical press process has been developed. The developed CAD system can generate the drawing of transfer die in mechanical press. Using these results from CAD system, it can generate the NC data to machine die's elements on the CAD system. This system can reduce design man-hours and human errors. In order to construct the system, it is used to automate the design process using knowledge base system. The developed system is based on the knowledge base system which is involved a lot of expert's technology in the practice field. Using AutoLISP language under the AutoCAD system, CTK customer language of SmartCAM is used as the overall CAD/CAM environment. Results of this system will be provide effective aids to the designer and manufacturer in this field.

• Korea Trade Review
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• v.47 no.1
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• pp.43-61
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• 2022

The purpose of this study is to classify the types of local market knowledge and knowledge sources in reverse knowledge transfer and analyze their relevance. To do so, first, we searched for papers related to the types of local knowledge published in 9 international business academic journals between 1988 and 2020, and derived four types of local market knowledge. Second, in order to classify the source of knowledge, we searched for papers related to network types published in 9 international business academic journals between 1988 and 2020, and divided them into 4 types to derive characteristics. Third, by examining the types of local market knowledge that can be obtained according to network types, a conceptual model was developed between them, and the suitability between local market knowledge and sources of knowledge was revealed through empirical analysis. Through empirical research on what kind of knowledge can be obtained depending on the knowledge sources, various business and academic implications can be provided to many companies.

• Journal of Information Technology Services
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• v.12 no.1
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• pp.163-171
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• 2013

As the kind of IT service on the internet is more and more diversifying and increasing, IT service's adverse effects also consistently occurring. Among them the incident of private information exposure is becoming social issues, especially the exposure of private information entered on-line resume is very serious. This paper investigates whether or not data is encrypted in data transfer section of major on-line job-search sites of Korea by using the packet analyzer such as "Wireshark." This paper judges whether or not the vulnerability, private information exposure, exists from the result of the investigation above and suggests countermeasures.

• International Journal of Air-Conditioning and Refrigeration
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• v.9 no.2
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• pp.69-76
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• 2001

The purpose of this research is to investigate the thermal performance of embossing surface sandwich panel and flat surface sandwich panel. To do this research, thermal performances in summer season at the six points of embossing surface sandwich panel and flat surface sandwich panel are investigated focusing on the temperature. Three kinds of embossing surface sandwich panel and one kind of flat surface sandwich panel are used for this research. At the same size of sandwich panel, the average temperature differences of flat surface sandwich panel between average temperature at the 0.5 mm below copper plate and average outside air temperature and surface temperature are higher than those of embossing surface sandwich panel. The average heat transfer rate of flat surface sandwich panel in higher than that of embossing surface sandwich panel. More study will be needed about the size of diameter and height of embossing, and materials of embossing surface sandwich panel.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.12
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• pp.2253-2258
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• 2008

To design micro flow sensor varying depending on temperature of driving heater in the detector of Oxide semiconductor, Markov chain MCM(MCMCM), which is a kind of stochastic and microscopic method, was introduced. The formulation for the thermal transfer equation based on the FDM to obtain the MCMCM solution was performed and investigated, in steady state case. MCMCM simulation was successfully applied, so that its application can be expanded to a three-dimensional model with inhomogeneous material and complicated boundary.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.11 no.5
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• pp.615-623
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• 1999

The objective of present study is to analyze a hot steel-tube cooling system as a kind of concentric triple-passage heat exchanger, whose inner tube is moving with a constant speed. Velocities and temperatures of an antioxidant gas flowing between inner and outer tubes are calculated theoretically for both laminar and turbulent flow regimes and used to give Nusselt numbers and friction factors with respect to various radius ratios and velocity ratios. In addition, it is shown that heat transfer coefficients based on ratios of average heat fluxes from inner and outer tubes might result in great errors for the temperature distributions of the flows, since the local heat transfer coefficients are dependent on the local heat flux ratios.