• Transactions of the Korean Society of Mechanical Engineers B
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• v.21 no.12
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• pp.1563-1575
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• 1997

To understand EHD nucleate boiling heat transfer enhancement, EHD effects on R-113 nucleate boiling heat transfer in a non-uniform electric field were investigated. The pool boiling heat transfer and the dynamic behavior of bubbles in d.c./a.c. electric fields under a saturated or subcooled boiling were studied by using a plate-wire electrode and a high speed camera. From the pool boiling heat transfer study, the shift of the pool boiling curve, the increase of the heat transfer and the delay of ONB and CHF points to higher heat fluxes were observed. From the dynamic behavior of bubbles, it was observed that bubbles departed away from the whole surface of the heated wire in radial direction due to EHD effects by a nonuniform electric field. With increasing applied voltages, the bubble size decreased and the active nucleation site and the departure number of bubbles showed the different trend. The present study indicates that the EHD nucleate boiling heat transfer is closely connection with the dynamic behavior of bubbles and the secondary flow induced near the heated surface. Therefore, the basic studies on the bubble behavior such as bubble frequency, bubble diameter, bubble velocity and flow characteristics are necessary for complete understanding of the enhancement mechanism of the boiling heat transfer using an electric field.

• The Transactions of the Korean Institute of Power Electronics
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• v.25 no.3
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• pp.181-187
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• 2020

In this study, we propose a spherical flux concentration structure for omnidirectional wireless power transfer. Omnidirectional wireless power transfer technology is a method that can transmit power to a transmitter located in an arbitrary position in a two-dimensional or three-dimensional space. However, to improve the power transfer distance in a wireless power transfer system, the diameter of the coil or the number of windings must increase, thereby increasing the size of the transmitter. The proposed transmitter structure adds a ferrite core inside the transmitter coil so that the magnetic flux generated by the transmitter is directed toward the position of the receiver. As a result, the flux linkage and the mutual inductance increase. By implementing the omnidirectional wireless power transfer system using the proposed structure, the power transfer distance can be improved by 65% compared with the conventional system without increasing the size of the transmitter. Simulation shows that the proposed spherical flux concentration structure increases the mutual inductance of the omnidirectional wireless power transmission system.

• The Korean Society of Law and Medicine
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• v.10 no.1
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• pp.389-420
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• 2009

Main Issue of Supreme Court Decision 2005Da16713 Delivered on June 24, 2005 is about the duty of medical care in the interhospital transfer of patients. According to the above Supreme Court Decision, in the interhospital transfer of patients, the decision to transfer should make from the aspect of medical treatment. The hospitals and doctors keep the duty of medical care. In addition to the duty for hospitals/doctors to check the capacity and availability of the hospital to which the patient is transferred, there are also duties to inform about emergency medical service and to sufficiently explain the need for the transfer, the medical conditions of the patient to be transferred and the hospital from which the patient is transferred. The hospital to which the patient is transferred must be thoroughly informed about matters such as the patient's conditions, the treatment the patient was given and reasons for transfer. including information upon referral, completeness of medical records, patient monitoring and so on. The interhospital transfer requires the consent of doctor belonging to the hospital to which the patient is transferred after the consideration of capacity and availability of the hospital and the informed consent of patients or legal representatives.

• Journal of the Semiconductor & Display Technology
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• v.9 no.2
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• pp.103-109
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• 2010

An ink transfer is modeled and experimentally verified using roll-to-roll electric direct gravure printing process. The ink transfer model based on the physical mechanism for the maximum ink transfer rate is proposed, and experimented by the electric printing machine in FDRC for the relations of the maximum ink transfer rates to the printing pressure, the operating speed, the operating tension, the surface roughness of substrates, and the contact angle between substrate and silver ink. The free ink split coefficient and immobilized ink under the maximum ink transfer rate are calculated by the physical parameter in a printing process and contact angle between substrates and ink. Numerical simulations and experimental studies were carried out to verify performances of the proposed ink transfer model. Results showed that the proposed ink transfer model was effective for the prediction of the amount of transferred ink to the substrate in a direct gravure printing systems.

• Design & Manufacturing
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• v.13 no.2
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• pp.22-29
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• 2019

This study conducted a research as to condensation heat transfer by using three types of flat micro multi-channel tubes with different processing of micro-fin and number of channels inside the pipes and different sizes of appearances. In addition, identical studies were conducted by using smoothing circular tubes with 5mm external diameter to study heat transfer coefficient. The condensation heat transfer coefficient showed an increase as the vapor quality and mass flux increased. However, each tube shows little differences compared to 400kg/m2s or identical in case the mass flux are 200kg/m2s and 100kg/m2s. The major reason for these factors is increase-decrease of heat transfer area that the flux type of refrigerant is exposed to the coolant's vapor with the effect of channel aspect ratio or micro-fin. In addition, the heat transfer coefficient was unrelated to the heat flux, and shows a rise as the saturation temperature gets lower, an effect that occurs from enhanced density. The physical factor of heat transfer coefficient increased as the channel's aspect ratio decreased. Additionally, the micro pin at the multi-channel type tube is decided as a disadvantageous factor to condensation heat enhancement factor. That is, due to the effect of aspect ratio or micro-fin, the increase-decrease of heat transfer area that the flux type of a refrigerant is exposed to the vapor is an important factor.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.11 no.1
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• pp.121-130
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• 2016

There is a growing interest in the technology transfer and commercialization both at home and abroad. Accordingly, this study looked at the concept of technology transfer and commercialization, identified the factors that should be taken into account in order to facilitate technology transfer and commercialization, and then performed a empirical analysis. As for the conventional technology transfer and commercialization, there was a tendency to limit its scope to the exploration, transfer and commercialization of technology itself. Here in this research, technology transfer and commercialization is defined the category to expand as various activities implemented in order to make sure that intellectual properties such as intangible technological developments, know-how, and knowledge are transferred between the relevant parties through a contract or negotiation, and the party to which the transfer is made can then further develop and exploit the technology into tangible products and other activities to obtain economic benefit out of that. In addition, the findings of the positive analysis of technology transfer and commercialization revealed that the focus of facilitating technology transfer has been on the technology itself, its management and securing efficiency of the systems and institutions involved in the technology transfer and commercialization. So there was lack of recognition as to the importance of financial support given to the phase of technology commercialization. This indicates that when it comes to the technology transfer and commercialization, quantitative performance has been the focus of interest such as patent application, registration, number of technology transfers, royalty, etc. So there was not enough understanding as to the issues of starting up a business, creating quality jobs through technology transfer and commercialization, which are directly related to the realization of the creative economy. In this regard, this research is expected to be used for the development for the future policies to boost technology transfer and commercialization as it suggests not only simply ensuring quantitative performance but also necessary to create the environment for the creation of the stable ecosystem for the parties involved in the technology transfer and commercialization and then to build circumstances in which creative economy can be realized.

• Korea-Australia Rheology Journal
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• v.19 no.3
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• pp.99-107
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• 2007

A nanofluid is a mixture of solid nanoparticles and a common base fluid. Nanofluids have shown great potential in improving the heat transfer properties of liquids. However, previous studies on the characteristics of nanofluids did not adequately explain the enhancement of heat transfer. This study examined the distribution of particles in a fluid and compared the mechanism for the enhancement of heat transfer in a nanofluid with that in a general microparticle suspension. A theoretical model was formulated with shear-induced particle migration, viscosity-induced particle migration, particle migration by Brownian motion, as well as the inertial migration of particles. The results of the simulation showed that there was no significant particle migration, with no change in particle concentration in the radial direction. A uniform particle concentration is very important in the heat transfer of a nanofluid. As the particle concentration and effective thermal conductivity at the wall region is lower than that of the bulk fluid, due to particle migration to the center of a microfluid, the addition of microparticles in a fluid does not affect the heat transfer properties of that fluid. However, in a nanofluid, particle migration to the center occurs quite slowly, and the particle migration flux is very small. Therefore, the effective thermal conductivity at the wall region increases with increasing addition of nanoparticles. This may be one reason why a nanofluid shows a good convective heat transfer performance.

• Journal of Embryo Transfer
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• v.13 no.1
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• pp.53-60
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• 1998

This study was carried out to establish an effective system for embryo transfer techniques by analyzing several factors affecting in-vivo embryo transfer in Korean cattle. Embryos produced in-vivo were transferred into a total of 301 recipients. The results obtained in studies on the factors affecting pregnancy rate after embryo transfer by condition of embryos were as follow ; 1. The pregnancy rate of 301 recipients was 45.2% and higher with fresh embryos than with frozen embryos(63.5% : 21.4%, P<0.01). Embryos superovurated by FSH-P had slightly greater than by SUPER-OV in pragnancy rate, athough these were no difference between two treatments. 2. The pregnancy rates of transferred morulae and blastocysts showed no difference between fresh and frozen embryos(63.5% : 63~6% ; 20.0% : 25.8%). However, the pregnancy rates by quality of flesh and frozen embryos were significantly different(P<0~05). The pregnancy rates were outstandingly high in the grade A, B of fresh embryos(59.0~66.4%), and in the grade A of frozen embryos(43.6%). 3. The number of transferred embryos showed no difference in pregnancy rate, but when frozen embryos transferred, the pregnancy rate was slightly higher with two embryos than that with one embryo.

• Child Health Nursing Research
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• v.28 no.2
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• pp.154-165
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• 2022

Purpose: This study aimed to analyze the concept of transfer anxiety in parents of children transferred from pediatric intensive care units to general wards. Methods: The hybrid model by Schwarz-Barcott and Kim was used to analyze the characteristics of transfer anxiety in parents of children transferred from pediatric intensive care units to general wards. Results: Transfer anxiety was defined by the following attributes: 1) stress concerning the adaptation process, 2) concern about the child's condition worsening due to the parent's caregiving, and 3) involuntary changes in daily life due to the treatment. Transfer anxiety has the following antecedents: 1) uncertainty; 2) a lack of knowledge about the illness, medical devices, and caregiving; and 3) a lack of social support. It resulted in 1) caregiver burden, 2) a decrease in the capacity for coping with caregiving, 3) delays in the child's physical and psychological recovery, and 4) decreased quality of life. Conclusion: It is necessary to develop an assessment scale that considers the attributes of transfer anxiety in parents of children transferred from pediatric intensive care units to general wards. Furthermore, an effective nursing intervention should be developed to reduce transfer anxiety.

• Proceedings of the KSR Conference
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• 2003.05a
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• pp.196-200
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• 2003

To fulfill the railroad station's duties efficiently, it is essential to view passenger transfer system within the railroad station and in the vicinity of railroad station in the context of broader technological developments in easy access to railroad station. To do the direct service to local station or easy transfer to other mass transportation modes, necessary courses for local govemments and each transportation agency involvement should be taken and long-term integrated transfer strategy must be found. The research designed here was designed to derive a general overview of the integrated transfer patterns with an emphasis on passenger intermodal transportation system.