• Journal of Korean Society of Transportation
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• v.27 no.5
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• pp.189-194
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• 2009

Transfer impedance is one of the most critical factors decreasing the competitive power of public transportation. Therefore, it is necessary to improve transfer impedance of KTX and rail station users in order to increase the usage of public transportation. Important factors influencing transfer decisions include exterior walking distance, interior walking distance, steps, and escalators. However, their comparative impedances are different. This study constructed a model for calculating transfer impedance based on bodily sensational transfer time in KTX and rail stations and calculated transfer impedance on major KTX and rail stations in Korea. The study results show that the addition of one escalator decreases travel time by one to three minutes. The calculated transfer impedance based on bodily sensational transfer time in this study can be utilized as objective criteria to compare transfer conditions of different KTX and rail stations and to prioritize them for facility improvement. The calculated transfer impedance also can be used as facility guidelines for designing a new transit center.

• Journal of Fisheries and Marine Sciences Education
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• v.16 no.2
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• pp.257-270
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• 2004

The two-phase closed thermosyphon is a heat transfer device capable of transfer large quantities of heat from a source to a sink by taking advantage of the high heat transfer rates associated with the evaporation and condensation of a working fluid within the device. A study was carried out with the performance of the heat transfer of the thermosyphon having 50, 60, 70, 80, 90 internal micro grooves in which boiling and condensation occur. A plain thermosyphon having the same inner and outer diameter as the grooved thermosyphon is also tested for comparison. Water, methanol and ethanol have been used as the working fluids. The liquid filling as the ratio of working fluid volume to total volume of thermosyphon, the inclination angle, micro grooves and operating temperature have been used as the experimental parameters. The heat flux and the boiling and the condensation heat transfer coefficient and overall heat transfer coefficient at the condenser and evaporator zone are estimated from the experimental results. The experimental results have been assessed and compared with existing correlations. Imura's and Kusuda's correlation for boiling showed in good agreement with experimental results within ${\pm}20$％ in plain thermosyphon. The maximum heat transfer rate was obtained when the liquid fill ratio was about 25%. The high heat transfer coefficient was found between 25o and 30o of inclination angle for water and between 20o and 25o for methanol and ethanol. The relatively high rates of heat transfer have been achieved in the thermosyphon with internal micro grooves. The micro grooved thermosyphon having 60 grooves shows the best heat transfer coefficient in both condensation and boiling. The maximum enhancement (i.e. the ratio of the heat transfer coefficients of the micro grooved thermosyphon to plain thermosyphon) is 2.5 for condensation and 2.3 for boiling.

• International Area Studies Review
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• v.22 no.1
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• pp.23-40
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• 2018

In the 2000s, China has been pushing the issue of San-Nong as a national priority. Farmland transfer, one of the solutions to the problem of San-Nong, has grown rapidly over the past decade. Especially, as farmland transfer was promoted, the rural economy developed and the living standards of the farmers improved greatly. However, the rigidity of farmland transfer type, which focuses on Zhuan-Bao method, hinders farmers' willingness to relocate to farmland transfer and ultimately acts as an obstacle in promoting massive farmland transfer. The purpose of this paper is to analyze the determinants of farmland transfer types and farmland transfer prices in Chinese farmers. Based on the results of the analysis, the following implications are suggested. First, farmers should be instructed to farmland transfer in a Ru-Gu manner; Second, the contract period must be long; Third, it is necessary to prepare countermeasures for the farmland transfer by crops; Fourth, Educational programs should be built for the farmers of farmland transfer.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.6 no.1
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• pp.39-48
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• 2016

The tacit knowledge transfer cultivate the value and mount of tacit knowledge. The tacit knowledge transfer plays the most important role for improving the competitiveness of the organization. Despite the tacit knowledge transfer is very important, the research related with tacit knowledge transfer has not been actively carried out. The barriers to tacit knowledge transfer interfere with the tacit knowledge transfer. The barriers to tacit knowledge transfer are lack of understanding knowledge experts, heavy over-work, insufficient compensation, trust shortage and knowledge stickiness. In order to overcome the barrier of the tacit knowledge transfer, it is necessary to promote knowledge broker. The knowledge broker is the foundation for the tacit knowledge transfer and the critical success factor for efficient tacit knowledge transfer. However, most research related on the knowledge broker had focused on the degree, centrality and density of the knowledge network. The framework is needed to performance indicator for diagnosing the tacit knowledge transfer. Therefore, we suggest the knowledge broker framework based on the social network analysis.

• Journal of Korea Foundry Society
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• v.14 no.3
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• pp.248-257
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• 1994

Research in heat transfer and solidification commonly involves experimentation and mathematical modeling with associated numerical analysis and computation. Inverse problems in heat transfer are part of this paradigm. During the solidification of metal casting, an interfacial heat transfer resistance exists at the boundary between the casting and the mold, and this heat transfer resistance usually varies with time. In the case of the squeeze casting the contact heat transfer resistance is decreased by pressure and ideal contact is almost accomplished. In the present work, heat transfer coefficient, which is inverse value of the heat transfer resistance, was used for convenience. A numerical technique, Non-Linear Estimation has been adopted for calculation of the casting/mold interfacial heat transfer coefficient during the squeeze casting process. In this method, the measured temperature data from experiment were used. The computational results were applied to the analysis of heat transfer and solidification.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.3395-3400
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• 2007

Heat transfer experiments at a vertical annulus passage were carried out in the SPHINX(Supercritical Pressure Heat Transfer Investigation for NeXt Generation) to investigate the heat transfer behaviors of supercritical $CO_2$. The collected test data are to be used for the reactor core design of the SCWR (SuperCritical Water-cooled Reactor). The mass flux was in the range of 400${\sim}$1200 kg/$m^2$s and the heat flux was chosen up to 150 kW/$m^2$. The selected pressures were 7.75 and 8.12 MPa. The heat transfer data were analyzed and compared with the previous tube test data. The test results showed that the heat transfer characteristics were similar to those of the tube in case of a normal heat transfer mode and degree of heat transfer deterioration became smaller than that in the tube. Comparison of the experimental heat transfer coefficients with the predicted ones by the existing correlations showed that there was not a distinct difference between the correlations.

• International Journal of Railway
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• v.2 no.2
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• pp.60-69
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• 2009

In recent years, technology developments in different countries, especially in newly industrialized countries, are extremely indebted to appropriate technology transfer by these countries. Nevertheless the technology transfer process in the present situation is complex, and its success is related to the coordination rate with the political, economic, social, and environmental objectives of countries. Today debates related to the transfer of the technical know how accompanied by equipment hardware has found remarkable importance such that countries seek increasing comprehensive capabilities in the field of transferred technology for which Preventive Maintenance (PM) is one of the aspects. This research with the purpose to determine the technological capability level and to study the role of PM in the effective & appropriate technology transfer in subway industry is carried out for presenting a suitable model for the technology transfer in this industry with an attitude towards the effects of principal PM factors. For this purpose, after the study of different and relevant models existing in the field of suitable methods for technology transfer, some equipment PM theories and models were selected as the base for the compilation of the questionnaire. With the help of questionnaire, main PM factors that are effective in the field of technology transfer were extracted, and finally, their effects on technology transfer were analyzed, identified and a comprehensive model suggested in this connection.

• Membrane and Water Treatment
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• v.2 no.3
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• pp.159-173
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• 2011

The air gap membrane distillation (AGMD) process was applied for water desalination. The main objective of the present work was to study the heat and mass transfer mechanism of the process. The experiments were performed on a flat sheet module using aqueous NaCl solutions as a feed. The membrane employed was hydrophobic PTFE of pore size 0.22 ${\mu}m$. A mathematical model is proposed to evaluate the membrane mass transfer coefficient, thermal boundary layers' heat transfer coefficients, membrane / liquid interface temperatures and the temperature polarization coefficients. The mass transfer model was validated by the experimentally and fitted well with the combined Knudsen and molecular diffusion mechanism. The mass transfer coefficient increased with an increase in feed bulk temperature. The experimental parameters such as, feed temperature, 313 to 333 K, feed velocity, 0.8 to 1.8 m/s (turbulent flow region) were analyzed. The permeation fluxes increased with feed temperature and velocity. The effect of feed bulk temperature on the boundary layers' heat transfer coefficients was shown and fairly discussed. The temperature polarization coefficient increased with feed velocity and decreased with temperature. The values obtained were 0.56 to 0.82, indicating the effective heat transfer of the system. The fouling was observed during the 90 h experimental run in the application of natural ground water and seawater. The time dependent fouling resistance can be added in the total transport resistance.

• Journal of Distribution Science
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• v.12 no.1
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• pp.35-46
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• 2014

Purpose - This Study aims to promote technology transfer commercialization and ultimately make contribution towards enhancement of the success rate of commercialization of technology transfer at national level by deducing the factors that impart influence on the negotiation at the time of technology trading between the seller and buyer of technology of public research institutions subjected to transfer and sales. Research design, data and methodology - This Study deduced 5 research hypotheses through preceding researches related to technology transfer commercialization related technology marketing for technology trading negotiation. This Study was conducted by verifying the hypotheses through multiple regression analysis. Results - As the result of the Study, the research hypothesis H1, 'Promotion of commercialization of technology transfer trading will be affected in accordance with the innate characteristic factors of the technology', and H5, 'Promotion of commercialization of technology transfer trading will be affected in accordance with the mutual factors of the parties of the technology trading', among the 5 research hypotheses were chosen. Conclusions - It was found that the technology seller must be able to demonstrate technological value of the technology being sold in order to successfully conclude technology transfer trading negotiation and mutual understanding and harmonious communication between the parties.

• Journal of Korean Society on Water Environment
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• v.26 no.6
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• pp.1008-1015
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• 2010

Discharged pollution load is varied as rainfall changes in the area with combined sewer system. Changes in discharged pollution load are directly related with those of sewer transfer flow. Therefore, it is important to identify the pattern of sewer transfer flow for the analysis of changes in discharged pollution load. This study reviewed the type of distribution of sewer transfer flow for 17 sewage treatment plants and developed simple formular to estimate sewer transfer flow as rainfall changes. 11 facilities showed to have some relation with rainfall in the change of sewer transfer flow but 6 facilities to have no relation. Relationships between rainfall amount and sewer transfer flow showed that 6 facilities out of 11 had relatively strong relationships above R2=0.5, which were considered to be affected directly by rainfall changes. The formular which explain the relationship between rainfall and sewer transfer flow can be applied in the analysis of rainfall effects on discharged pollution load, therefore, the more appropriate evaluation will be done.