• Nuclear Engineering and Technology
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• v.28 no.6
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• pp.532-541
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• 1996

Theoretical and numerical study on heat transfer and evaporation in the vertical channel has been carried out and basic correlations have been derived for the heat transfer evaluation of PCCS. Analysis program was developed with low-Reynolds-number k-$\varepsilon$ model and surface transfer rates were calculated for the turbulent natural convection in the vertical channel. In relation to dry cooling by buoyancy-driven air, first, the system parameters which govern overall heat transfer rate are determined through the adequate nondimensionalization procedure. After comparison with existing experimental data, numerical results are used to derive heat transfer correlation by sensitivity calculations. In relation to wet cooling by falling water film, numerical analysis are carried out for evaporation process with real film surface conditions and evaporation correlation is derived through analogy concept and correction factors.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.11 no.6
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• pp.861-870
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• 1999

An experimental study was carried out to investigate the effects of using various shapes of turbulence promoter on the heat-transfer enhancement of 2-D and 3-D arrays of rectangular modules in a rectangular channel for design of noiseless and low-powered cooling fan in the electronic systems. Measurements of heat/mass transfer coefficients were made using a naphthalene sublimation technique, and the friction factors were measured for Reynolds numbers in the range$3.3{\time}10^3$~$1.6{\time}10^4$. Flow visualization was peformed by oil-film method. It was found that heat transfer and pressure drop increased remarkably due to the existence of the promoter. The results of the performance evaluation based on equal pumping power were showed that substantial heat-transfer enhancement was obtained at low Reynolds number range by use of a turbulence promoter.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.18 no.36
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• pp.297-306
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• 1995

An automatic transfer line consists of several stages(groups of stations) in series into one system by a common transfer mechanism and a common control system. In this system losses of the efficiency are evidenced in periods where a stage is forcod down- starved or blocked. The efficiency of an automatic transfer line can be improved by providing buffer storages between a stage or the length of line common senses there are several critical factors, system configurations relative position, and buffer capacity allocations in automatic transfer line are considered with a point of view production rates, average stock, and mean delay. The propose of this paper is to provide the robust designs by Taguchi method which improve the efficiency of four-stage transfer line.

• Asia-Pacific Journal of Business
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• v.10 no.3
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• pp.53-67
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• 2019

Reverse knowledge transfer has been an important research theme in the literature on multinational corporations (MNCs). This paper proposes major determinants of MNC headquarters' willingness to adopt and use marketing knowledge from their subsidiaries. We argue that the willingness will be jointly determined by both the headquarter's absorptive capacity and the focal subsidiary's transfer capacity and willingness to transfer. In addition, we argue that these capability and motivation effects are moderated by (1) institutional distance between home and the focal host country, (2) the need to unlearn existing routines, and (3) types of entry modes. This paper contributes to the reverse knowledge transfer literature by proposing the argument that both motivational and capability factors are likely to determine the MNC parents' willingness to adopt and use marketing knowledge from their subsidiaries.

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2005.10a
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• pp.147-148
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• 2005

• Proceedings of the KWS Conference
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• 2000.04a
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• pp.109-112
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• 2000

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.9 no.2
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• pp.210-220
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• 1997

This study is to systematically analyze the effect of various kinds of design parameters on heat transfer and pressure drop characteristics of heat exchanger with a slit fin. TAGUCHI method, known to us as a very reasonable tool in the parametric study, is employed in the present work. Experimental factors have been limited to seven cases, considering the production of sample and the cost. The 18 kinds of large scale models are made by compounding level on each factor and the heat transfer and flow characteristics on each model has been analyzed. The present results allow us to be able to quantitatively estimate the various parameters affecting the heat exchanger performance, and main factors for an optimum design of a heat exchanger have been selected. The optimum design value on each parameter was presented and the reproducibility on the results was guaranteed.

• Journal of the Korean Home Economics Association
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• v.40 no.6
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• pp.99-115
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• 2002

The purpose of this study is to investigate the allocation criteria types in transferring economic resources to adult children from the adult-childhood of children to parent's death based on theoretical backgrounds. The research results can be summarized as follows: 1) The mean of allocation criterion of exchange was the highest, the next was the criterion of compensation, and the criterion related birth factors was the lowest. 2) Allocation criteria dimensions of economic resources transfers composed of compensation, exchange, and birth factors were classified into 4 types: $\circled1$ the type that parents transfer to compensate economic status of children, $\circled2$ the type that parents transfer more resources to children who take more care of their parents, $\circled3$ the type that parents transfer more resources to primogeniture or sons, $\circled4$ the mixed type that uses the exchange criterion, the compensation criterion, and the criterion related birth factors. 3) The variables which have significance on the types of allocation criteria were age, the number of children, and marital status. The results of the study suggests the implications of income redistribution policy, financial resource management and saving products development, and the law to motivate care of parents.

• Journal of Families and Better Life
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• v.29 no.6
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• pp.137-151
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• 2011

This study examines the condition of transfers between mothers and adult children, analyzing the influencing factors in such transfers. Specifically the study examines the influence of financial transfers and economic resources on financial transfers and grandchild caregiving between mothers and adult children. The sample of 3719 mothers with adult children was extracted from the first wave of the Korean Longitudinal Survey of Women and Families. The major findings are as follows. Mothers's socio-demographic characteristics are important factors in explaining financial transfers between mothers and adult children. Mothers who have jobs and spouses are more likely to provide economic resource to their adult children than those who don't have. In terms of receiving economic resources from adult children, statistically meaningful factors are mothers' age, labor market participation, marital status, household income, household asset, and children's labor market participation. Especially, labor market participation of mothers and adult children is statistically powerful factor in financial transfers and caregiving.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.04a
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• pp.714-719
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• 2000

This paper describes a transfer matrix approach to analyze the dynamics of a high sped flexible rotor system supported at 2 positions by five ceramic bearings. The rotor system is modelled as lumped parameters in which many factors are considered not only lumped inertia or mass, bending moment, shear force but also gyroscopic effect and unbalance. The equation of motion is derived in the transfer matrix form, from which the eigenvalues equation is also derived. The transfer natural frequencies and modes. The eigenvalues, eigenmodes, campbell diagram, whirling critical speed, whirling modes, and the response of unbalance are calculated and discussed.