• Progress in Superconductivity
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• v.10 no.1
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• pp.60-67
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• 2008

We present domestic efforts for superconducting fault current limiter (SFCL) application in the Korea Electric Power Corporation (KEPCO) grid and pending points at issue. KEPCO's decision to upgrade the 154 kV/22.9 kV main transformer from 60 MVA to 100 MVA cast a problem of high fault current in the 22.9 kV distribution lines. The grid planners supported adopting an SFCL to control the fault current. This environment friendly to SFCL application must be highly dependent upon the successful development of SFCL having specifications that domestic utility required. The required conditions are (1) small size of not greater than twice of 22.9 kV gas insulated switch-gear (GIS), (2) sustainability of current limitation without the line breaking by circuit breakers (CB) for maximum 1.5 seconds. Also, optionally, recommended is (3) the reclosing capability. Conventional resistive SFCLs do not meet (1) $\sim$ (3) all together. A hybrid SFCL is an excellent solution to meet the conditions. The hybrid SFCL consists of HTS SFCL components for fault detection and line commutation, a fast switch (FS) to break the primary path, and a limiter. This characteristic structure not only enables excellent current limiting performances and the reclosing capability, but also allows drastic reduction of HTS volume and small size of the cryostat, resulting in economic feasibility and compactness of the equipment. External current limiter also enables long term limitation since it is far less sensitive to heat generation than HTS. Semi-active operation is another advantage of the hybrid structure. We will discuss more pending points at issues such as maintenance-free long term operation, small size to accommodate the in-house substation, passive and active control, back-up plans, diagnosis, and so on.

• Journal of the Korean Vacuum Society
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• v.6 no.1
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• pp.1-8
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• 1997

The contamination structure and process on SUS 316 under various exposure conditions were investigated using x-ray photoelectron spectroscopy. The metal-oxide, metal-H-oxides, CO, COH, and $C_xH_y$ are the main components of contaminants on the SUS surface. The compositional profiles of the contaminants are shown to be $C_xH_y$/CO(COH)/metal-oxide on SUS. The contamination proceeds in two steps. The oxidation of the metallic constituents followed by adsorption of hydrocarbons. Under UHV conditions the contamination is mainly due to the oxidation, and, as the exposure time increases, the oxidation continues. In HV or higher pressure, most of the oxides are formed almost immediately after exposure and as the exposure time increases the contamination of hydrocarbons continues to grow. For the SUS sample exposed to atmosphere, the metal oxide is distributed deep inside the surface with an exponentially decreasing concentration, and its thickness is nearly in the order of photoelectron mean free path. It is also seen that the Fe oxide is segregated over Cr oxide in the highly oxidized samples.

• Fire Science and Engineering
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• v.16 no.4
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• pp.20-27
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• 2002

This study in focused on proposing the improvement plans for refuge and fire-fighting facilities in large shopping malls that are radically spreading. The main subjects are as follows. - The refuge measure for large shopping malls - Problems of installing the refuge facilities in stores and the solutions - Problems of installing the incendiary facilities in stores and the solutions - Problems of installing the indoor fire plug in stores and the solutions As result of the study, it has turned out that escape stairs which are set up according to the standard of size in the process of design plan, have to be decided for their amount, position, specification, etc, in consideration of the number of residents. It is also required to tighten a standard of installing a sprinkler instead of lightening the fire-fighting section in stores, considering obstacles due to facilities installed and procurement of the escape path. In addition, it needs to lighten a standard of installing the indoor fire plug, which is voluntarily set up at the store section incase of installing a sprinkler to make a practical fire-fighting facility available.

• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.2
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• pp.100-106
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• 2006

The behavior of spray impinging on the inclined constant temperature flat plate was experimentally investigated. To clarify the wall effect of a high pressure DISI injector, a relative angle of the inclined wall to a spray axis was varied. Spray penetration along the wall was observed optically and it was compared with that of a Fan spray type and Swirl type spray. To evaluate various spray motion quantitatively, a spray path penetration which describe the development of a spray tip along the wall was newly introduced. To observe the structure of an impinging spray, it was visualized by a controlled stroboscope light and its visualized image was captured on an CCD camera. Using the digital image of impinging spray $H_x$ and $R_x$ was extracted to clarify the structure of impinging spray. The main parameter of the relative position of the wall was the inclined angle which was defined as the angle was varied from $0^{\circ}$ (vertical impingement) to $60^{\circ}$ at the same condition.

• Journal of Korean Society of Steel Construction
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• v.21 no.1
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• pp.93-103
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• 2009

Two-girder bridge is composed of primary members such as deck slab and main girder, and secondary member such as cross beam, vertical and horizontal stiffeners etc,. Two-girder bridge is prescribed as a non-redundant load path structure in the ASSHTO and the Korean Highway Bridge Design Code. Such structure is that if one girder is damaged, problems of function and safety of the bridge are caused. From the reasons, fatigue cracks in two-girder bridge can affect safety of the bridge seriously. Therefore, in this paper, fatigue evaluation was performed at connection parts of vertical stiffener and web with radius of curvature of scallop of vertical stiffener and thickness of web as variables. Such joint is known as a detail which has high possibility of fatigue crack in the bridge. Based upon the analytical results, preferable joint detail in terms of fatigue and simple empirical formula for fatigue evaluation of the detail were suggested.

• Journal of the Korean Vacuum Society
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• v.8 no.1
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• pp.13-19
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• 1999

Total reflection X-ray fluorescence spectroscopy using synchrotron radiation source called as TRSFA was explored to achieve high sensitivities to impurity metals on Si wafer surface. It consists of monochromating part to select a specific wavelength, slit part to shield direct beam and to control monochromated beam, and main chamber to dectect fluorescent X-ray counts of impurities on si wafer. Monochromated X-ray of 10.90 KeV was selected and the optimum total reflection condition on silicon wafer was obtained through tuning the dead time and fluorescent X-ray count of Si and Fe. TRSFA system could increase the sensitivity as high as 50 times in comparision with TRXFA using normal X-ray source. But the trend was varied since the surface conditions of Si wafers and, therefore, the reflectivities were different. Furthemore, there seems to be a promising path to reaching a detection limit useful to the next generation metal impurities control, because Fe impurity below to the $5\times10^{9}\textrm{atomas/cm}^2$ can be detectable through the developed TRSFA system.

• Health Policy and Management
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• v.18 no.3
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• pp.1-17
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• 2008

The measurement and management of patient satisfaction has become one of the key issues in the last two decades. Hospitals must thoroughly understand the needs of their customers and design products and health services that meet and exceed their expectations. The importance-performance analysis(IPA) is a widely used analytical technique that yields strategies for managing customer satisfaction in a variety of applications. IP A is a two-dimensional grid based on customer-perceived importance of quality attributes and attribute performance. Depending on the interplay of these two dimensions, four strategies can be derived. The aim of this study is to develop the management strategies for improving patient satisfaction in university hospitals using the I-P analysis. The attributes on inpatient service quality in 4 university hospitals was investigated using the Martilla and James(l977)' s a mean adjusted I-P grid where the axes of the grid cross at the average rating point of all items. The patient satisfaction questionnaires were completed by 600 hospital inpatients. The main statistical methods are path analysis and IPA with SPSS 12.0 and AMOS 4.0 statistical softwares. The two attributes, physician and medical service, administrative staff kindness attributes position in first quadrant(Keep Up the Good domain). The nurse and nursing service attributes position in second quadrant(Possible Overkill domain). The two attributes, convenience of check-in service, facilities and physical environment position in third quadrant(Low Priority domain). Finally the quality of inpatient service(food etc.) attributes position in fourth quadrant(Concentrate Here domain). These findings show various implications on the development of strategies in university hospitals in the future. It was determined that quality of inpatient service(food etc.) need to concentrate more on investments. These investments include a taste, price, proper provision of food service and quick response of pain management. A low priority was given to investment in streamlining the check-in process of inpatient and hospital facilities and physical environment in the long run.

• Journal of the Korean Society of Clothing and Textiles
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• v.43 no.6
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• pp.910-929
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• 2019

This study identifies the effects of the characteristics of an online shopping cart based on the theory of psychological ownership. This study created experimental stimuli similar to the actual fashion website in order to derive the exact emotional and behavioral responses of participants. To test the hypotheses, four experimental groups of 2 (personalization: high / low) × 2 (accessibility: high / low) were formed with between-subject design. We selected 201 women in 20-30s as participants and they responded to an online survey after experiencing website stimuli. The collected data were analyzed using SPSS 25.0 and SPSS PROCESS Macro program. The results show that the effects of personalization of an online shopping cart on the purchase intention of the fashion product in the cart is significant; in addition, the main effect of personalization of cart on consumer's psychological ownership was confirmed. It was also found that the path of personalization of the online shopping cart to purchase intention through psychological ownership was significant. The findings of this study contributes to the extension of online shopping cart research and provide suggestions to recognize the important role of psychological ownership in increasing the purchase conversion rate.

• Health Policy and Management
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• v.15 no.3
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• pp.60-78
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• 2005

The main objective of this study is to define the nature of the patient service quality of Health Centers, and based on that, to examine the causal relationship of Health Center visitor's perceived service quality with overall satisfaction, intention to revisit and intention to recommend. Data are collected on the basis of the second field survey of '3rd Regional Health Care Planning' operated by the Ministry of Health and Welfare(MOHW). In this study, the 24 patient satisfaction questions are used as outcome indicators. The samples are 3,091 patients who visited 68 Health Centers. The reliability and validity of patient service quality items was evaluated. Finally, the Structural Equation Modeling(SEM) analysis was conducted to find a causal relationship of service quality, patient satisfaction, intention to revisit and intention to recommend. This study shows firstly, the dimension of patient service quality was categorized into 3 dimensions, that is, facilities and environment, staff kindness, and convenience of utilization process. Secondly, the reliability and validity of patient service quality items was satisfied. Lastly, the total effect of convenience of utilization process factor on satisfaction(path coefficients=1.721), intention to revisit(0.843) and intention to recommend(0.696) is more higher than other variables. These findings imply that the quality of various services concerning convenience of utilization process at Health Centers should be improved to satisfy the health need of community people and improve the service quality of Health Centers.

• The Korean Journal of Health Service Management
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• v.8 no.2
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• pp.49-59
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• 2014

This study attempted to provide some implications for human resource management of health services organizations by investigating the influence of job rotation on motivation and organizational commitment. For empirical analysis, a study model based on literature review of previous researches was developed, and a survey was conducted for the employees of 8 hospitals located in Busan area. In processing the data, frequency analysis, correlation analysis and path analysis were performed using SPSS 18.0 and AMOS 18.0. Main results of empirical analysis can be summarized as follows: First, procedure of job rotation, did not significantly affect tissue immersion and stimulation, but effect of job rotation, has been found to provide a significant effect. Second, motivation was shown to have a significant influence on emotional and normative commitments, sub-factors of organizational commitment variable. In conclusion, suggest that intentions and opinions of the organizational members need to be actively reflected in job rotations of which the effect can be maximized when they are regularly and reasonably implemented.