• Proceedings of the Materials Research Society of Korea Conference
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• 2009.11a
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• pp.24.1-24.1
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• 2009

Tantalum carbo-nitride($T_aC_xN_y$) films were deposited with chemical vapor deposition(CVD) using tert-butylimido tris-diethylamido tantalum (TBTDET, $^tBu-N=Ta-(NEt_2)_3$, $Et=C_2H_5$, $^tBu=C(CH_3)_3$) between $350^{\circ}C$ and $600^{\circ}C$ with argon as a carrier gas. Fourier transform infrared (FT-IR)spectroscopy was used to study the thermal decomposition behavior of TBTDET in the gas phase. When the temperature was increased, C-H and C-N bonding of TBTDET disappeared and the peaks of ethylene appeared above $450^{\circ}C$ in the gas phase. The growth rate and film density of $T_aC_xN_y$ film were in the range of 0.1nm/min to 1.30nm/min and of $8.92g/cm^3$ to $10.6g/cm^3$ depending on the deposition temperature. $T_aC_xN_y$ films deposited below $400^{\circ}C$ were amorphous and became polycrystal line above $500^{\circ}C$. It was confirmed that the $T_aC_xN_y$ film was a mixture of TaC, graphite, $Ta_3N_5$, TaN, and $Ta_2O_5$ phases and the oxide phase was formed from the post deposition oxygen uptake. With the increase of the deposition temperature, the TaN phase was increased over TaC and $Ta_3N_5$ and crystallinity, work function, conductivity and density of the film were increased. Also the oxygen uptake was decreased due to the increase of the film density. With the increase of the TaC phase in $T_aC_xN_y$ film, the work function was decreased to 4.25eV and with the increase of the TaN phase in $T_aC_xN_y$ film,it was increased to 4.48eV.

• Journal of the Korean Society for information Management
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• v.30 no.2
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• pp.269-295
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• 2013

This study purported to study the uses of information and communication technology (ICT) tools in their daily life among the undergraduate and graduate students majoring science and engineering. It also examined the purposes of the uses of the major ICT tools, the differences in their information technology uses between graduate and undergraduate students. The data were collected from 83 undergraduate and graduate students from four universities using content analysis of an observational logs and a survey questionnaire. The observational logs were collected using an instant message application available on a smart phone. Study results revealed desktop computers, laptop computers, and smart phones as the three most heavily used ICT tools among the participants and typical situations students use each of the three tools. There were also sharp distinctions between graduate and undergraduate students in their selection of the tools, and distinctions between work and non-work situations. The findings of this study can be used to redesign information services and systems for the scientists and engineers in the next generation.

• Nuclear Engineering and Technology
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• v.47 no.5
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• pp.608-616
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• 2015

The migration of silver (Ag) in silicon carbide (SiC) and $^{110m}Ag$ through SiC of irradiated tristructural isotropic (TRISO) fuel has been studied for the past three to four decades. However, there is no satisfactory explanation for the transport mechanism of Ag in SiC. In this work, the diffusion coefficients of Ag measured and/or estimated in previous studies were reviewed, and then pre-exponential factors and activation energies from the previous experiments were evaluated using Arrhenius equation. The activation energy is $247.4kJ{\cdot}mol^{-1}$ from Ag paste experiments between two SiC layers produced using fluidized-bed chemical vapor deposition (FBCVD), $125.3kJ{\cdot}mol^{-1}$ from integral release experiments (annealing of irradiated TRISO fuel), $121.8kJ{\cdot}mol^{-1}$ from fractional Ag release during irradiation of TRISO fuel in high flux reactor (HFR), and $274.8kJ{\cdot}mol^{-1}$ from Ag ion implantation experiments, respectively. The activation energy from ion implantation experiments is greater than that from Ag paste, fractional release and integral release, and the activation energy from Ag paste experiments is approximately two times greater than that from integral release experiments and fractional Ag release during the irradiation of TRISO fuel in HFR. The pre-exponential factors are also very different depending on the experimental methods and estimation. From a comparison of the pre-exponential factors and activation energies, it can be analogized that the diffusion mechanism of Ag using ion implantation experiment is different from other experiments, such as a Ag paste experiment, integral release experiments, and heating experiments after irradiating TRISO fuel in HFR. However, the results of this work do not support the long held assumption that Ag release from FBCVD-SiC, used for the coating layer in TRISO fuel, is dominated by grain boundary diffusion. In order to understand in detail the transport mechanism of Ag through the coating layer, FBCVD-SiC in TRISO fuel, a microstructural change caused by neutron irradiation during operation has to be fully considered.

• Korean Journal of Family Social Work
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• no.54
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• pp.187-224
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• 2016

This study aims to investigate the effect of psychosocial aging on age integration and the moderating effect of Familism and Family solidarity. In particular, this study has significance for establishing a basis of practical and political intervention in family level for improving age integration. We employed data from the 'Ageing Society Awareness Investigation' funded by Korean National Research Foundation in 2014. Our analysis sample consisted of 702 adults who were from 40 to 90 years old. Also, this study conducted descriptive statistics and multiple regression analysis by using STATA13. First of all, the lower psychosocial aging awareness is the higher age integration awareness. Familism and family solidarity were not a significant predictor for age integration. However, the interaction effects between familism as well as family solidarity and psychosocial aging ware statistically associated with age integration. That is to say that as psychosocial aging is negative, when decrease age integration, the net moderating effects of familism and family solidarity were found between age integration and psychosocial aging. Based on the results, this study provides implications that reinforcing family value and promoting interaction and solidarity with family members are positively contributed to age integration awareness at this point of negative psychosocial aging.

• Nuclear Engineering and Technology
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• v.42 no.4
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• pp.382-393
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• 2010

Thermal mixing by steam jets in a pool is dominantly influenced by a turbulent water jet generated by the condensing steam jets, and the proper prediction of this turbulent jet behavior is critical for the pool mixing analysis. A turbulent jet flow induced by a steam jet discharged through a vertical upward single hole into a subcooled water pool was subjected to computational fluid dynamics (CFD) analysis. Based on the small-scale test data derived under a horizontal steam discharging condition, this analysis was performed to validate a CFD method of analysis previously developed for condensing jet-induced pool mixing phenomena. In previous validation work, the CFD results and the test data for a limited range of radial and axial directions were compared in terms of profiles of the turbulent jet velocity and temperature. Furthermore, the behavior of the turbulent jet induced by the steam jet through a horizontal single hole in a subcooled water pool failed to show the exact axisymmetric flow pattern with regards to an overall pool mixing, whereas the CFD analysis was done with an axisymmetric grid model. Therefore, another new small-scale test was conducted under a vertical upward steam discharging condition. The purpose of this test was to generate the velocity and temperature profiles of the turbulent jet by expanding the measurement ranges from the jet center to a location at about 5% of $U_m$ and 10 cm to 30 cm from the exit of the discharge nozzle. The results of the new CFD analysis show that the recommended CFD model of the high turbulent intensity of 40% for the turbulent jet and the fine mesh grid model can accurately predict the test results within an error rate of about 10%. In this work, the turbulent jet model, which is used to simply predict the temperature and velocity profiles along the axial and radial directions by means of the empirical correlations and Tollmien's theory was improved on the basis of the new test data. The results validate the CFD model of analysis. Furthermore, the turbulent jet model developed in this study can be used to analyze pool thermal mixing when an ellipsoidal steam jet is discharged under a high steam mass flux in a subcooled water pool.

• Journal of vocational education research
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• v.35 no.6
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• pp.113-141
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• 2016

The apprenticeship training is given as a solution of the youth unemployment problem. The apprenticeship is a system that companies hire and instruct trainees and is implemented in various countries. In Korea, there is a Korean work-learning dual system which is managed by the government rather than the company itself. This Study analyzed Germany, Switzerland and Austria's apprenticeship training system and compared common factors of apprenticeship system, a trainer in company and cost-benefit analysis. The result of the study can be shown as follows. First, Germany operates practical training, meanwhile Switzerland and Austria provide a pre-education course before students enter the upper-secondary VET course. Second, Germany and Switzerland give a single type apprenticeship training, whereas Austria runs a modularization system, which enables students to specify their skills and improves clarity. Third, social partners as well as the government, states, companies/schools actively participate in apprenticeship. Fourth, there is a suitable trainer's qualification system in all countries. Finally, Germany and Austria's companies cause larger cost than benefit in apprenticeship. On the other hand, Switzerland gets larger net-benefit than cost. We can give implications to the Korean work-learning dual system based on this study.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.36 no.6
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• pp.457-467
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• 2018

Currently, the regulation and rules for public surveying and the UCPs (Unified Control Points) adapts those of the triangulated traverse surveying. In addition, such regulations do not take account of the unique characteristics of GNSS (Global Navigation Satellite System) surveying, thus there are difficulties in field work and data processing afterwards. A detailed procesure of GNSS processing has not yet been described either, and the verification of accuracy does not follow the generic standards. In order to propose an appropriate procedure for field surveys, we processed a short session (30 minutes) based on the scenarios similar to actual situations. The reference network in Seoul was used to process the same data span for 3 days. The temporal variation during the day was evaluated as well. We analyzed the accuracy of the estimated coordinates depending on the parameterization of tropospheric delay, which was compared with the 24-hr static processing results. Estimating the tropospheric delay is advantageous for the accuracy and stability of the coordinates, resulting in about 5 mm and 10 mm of RMSE (Root Mean Squared Error) for horizontal and vertical components, respectively. Based on the test results, we propose a procedure to estimate the daily solution and then combine them to estimate the final solution by applying the minimum constraints (no-net-translation condition). It is necessary to develop a web-based processing system using a high-end softwares. Additionally, it is also required to standardize the ID of the public control points and the UCPs for the automatic GNSS processing.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.33 no.1
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• pp.71-94
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• 2022

While small libraries have steadily increased in quantity, parts of qualitative growth such as lack of manpower and poor operation have been pointed out as problems. Accordingly, with the aim of establishing a foundation for linkage and cooperation between public libraries and small libraries, the small library itinerant librarians project has been promoted since 2010, and its scale has been continuously expanding. However, the lack of manpower and poor operation still remain tasks to be solved, and the poor treatment and job environment of itinerant librarians have not improved. In this context, this study aims to examine the problems of small libraries and job problems experienced by itinerant librarians and to find ways to improve the job environment of itinerant librarians based on this. Through the analysis of previous studies, small libraries and net companies were investigated, and in-depth interviews were conducted with participants related to itinerant librarians and small libraries. Through interview data analysis, a total of 17 meaning topics were extracted, including 'lack of work authority', 'lack of work manual', 'lack of communication, community', 'lack of integrated operating system', 'poor treatment and working environment', 'malicious user', and 'lack of belonging'. Based on this, four improvement measures were proposed, including the improvement of the job authority and standard regulations of itinerant librarians, the establishment of a community organization, job security guarantees, and job education reinforcement.

• Journal of Service Research and Studies
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• v.11 no.1
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• pp.31-44
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• 2021

The net function of the domestic medical insurance system is highly regarded, but due to the problem of incomplete coverage, the public wants to secure coverage through private medical insurance subscription. As a result, the subscription rate of private medical insurance has recently increased, and the billing rate has also increased. As the number of people seeking private medical insurance increased, workers at private medical insurance companies are experiencing increased job stress and side effects, especially for insurance reviewers who are in charge of paying insurance, such as communicating with customers who claimed insurance and contributing to the company's profit. In response, this study analyzed the effects of job stress on mental health of insurance reviewers and conducted a descriptive survey study to reduce job stress of insurance reviewers and promote mental health. The analysis shows that job stress for insurance reviewers has a significant impact on mental health (+). In detail, job stress has a significant impact on all four factors: social performance and self-confidence, depression, sleeping disturbance and anxiety, and general well-being and vitality. This study showed that job stress in insurance reviewers has a significant (+) impact on mental health. Job stress can cause side effects in organizational aspects, such as reducing enthusiasm for job performance and increasing turnover and resignation rates, but it can also worsen individual physical health and cause diseases such as depression and anxiety, causing mental health to be impoverished. Therefore, in order to prevent this, appropriate work stress prevention methods and countermeasures should be provided to help reduce work stress and improve mental health.

• Journal of the Mineralogical Society of Korea
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• v.5 no.2
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• pp.109-121
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• 1992

For the purpose of mineralogical and chemical study on the topazes from various localities of world(Brzail, China, India, Nigeria and Sri Lanka), electron microprobe analysis(EPMA), neutron activation analysis(NAA), X-ray diffractometry, Raman spectroscopy, etch test, scanning electron microscopy, refractive index, specific gravity, fluid inclusion were performed. The chemical composition in topaz was discussed along with its physical and structural properties. Variations in the unit-cell dimension and physical properties of topaz were found to have a close relations in the unit-cell dimension and physical properties of topaz were found to have a close relationship with extent of substitution of $OH^-\;for\;F^-$. According to neutron activation analyses, the trace elements had no effects on the physical properties of topaz. Raman spectra showed that the peaks of topaz were different in intensity from one locality to another. Etching defects in topaz includes negative crystal defect o point-bottom pit(India, Nigeria) and net work defect of curl-bottom pit(Brazil, China). Fluid inclusions in topaz may be classiffied into liquid $CO_2$-bearing inclusion, gaseous inclusion, halite, sylvite-bearing inclusion and liquid inclusion. The results of this study can be useful to devising artificial coloring methods for topaz with different mineralogical compositions.