• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.10
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• pp.1413-1420
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• 2013

This paper proposes a novel compact MIMO antenna which has miniaturized radiators and their row correlation coefficient, working for the LTE mobile communication, and its SAR is observed. Each of the proposed radiators has a shape of staircase and the bandwidth is twice larger than the conventional PIFA as 600MHz(21%) in 2.5 GHz - 3.15 GHz. And the area of the radiators is $16.5mm{\times}9.7mm$ proper for a handheld device. Also, by adding a planar mushroom decoupling structure between the radiators, the isolation is improved. The design has been carried out using the commercial full-wave time-domain EM solver and the finalized MIMO antenna has the return loss less than -10 dB in the LTE band, the isolation better than 20 dB and the efficiency more than 90% with the gain of 4.3 dB. Regarding the SAR of the antenna, it is observed that the average SAR value of 1g is estimated as 1.37W/Kg, which is lower than the SAR standard.

• Journal of Power System Engineering
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• v.19 no.3
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• pp.11-15
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• 2015

In this paper, the multi-point hydrogen detection system based on the combination of the hetero-core optical fiber SPR hydrogen tip sensor and interrogator by pseudorandom noise (PN) code correlation reflectometry has been developed. In a light intensity-based experiment with an LED operating at 850 nm, it has been presented that a transmitted loss change of 0.32dB was induced with a response time of 25 s for 4% $H_2$ in $N_2$ in the case of the 25-nm Au, 60-nm $Ta_2O_5$, and 5-nm Pd multi-layers film. The proposed sensor characteristic shows excellent reproducibility in terms of loss level and time response for the in- and out- $H_2$ action. In addition, in the experiment for multi-point hydrogen detection, all sensors show the real-time response for 4% hydrogen adding with reproducible working. As a result, the real-time multi-point hydrogen detection could be realized by means of the combination of interrogating system and hetero-core optical fiber SPR hydrogen tip sensors.

• Journal of the Korean Home Economics Association
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• v.35 no.5
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• pp.141-150
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• 1997

The purpose of this study was the development of the parenting stress scale, necessary to understand the details of the difficulties for a working mother having children from infant to preschooler. Relevant works were reviewed to collect 44 items for the questionnaire from the previous researchs, and additional 34 are combined as a set of measure items. The 78 items were analyzed for the fitness of structure based on the chi-square test and Cramer's V coefficients, and 35 were selected as a final set for the questionnaire. Further factor analysis on the 35 items showed that they could be selected 32 items of the 35 item scale and composed of 3 subscales; namely, the first factor(12 items) as‘typical stress due to the parenting’, the second(12 items) as‘pressures pertaining to the parental role and distress’, and the third(8 items) as’guilty to the parenting by others’. This final questionnaire composed of 32 items was also tested for the concurrent validity based on Pearson's correlation with Goldberg's General Health Questionnaire (GHQ), which is a well-known index to represent the socio-psychological stress. The correlation factor is .41(p＜.001), which justifies the fitness of the newly designed questionnaire. To find the confidence level, the Cronbach α was evaluated, which results .88 for the overall questionnaire and ranges between .76 and .82 for each subcale. This parenting scale can be also utilized as a measure to exploit proper programs for the parent-child relations, parent education and rehabitilation of the family function.

• Journal of Korean Academy of Nursing
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• v.27 no.1
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• pp.189-201
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• 1997

This study was designed to test the relationship between effectiveness of nursing organizations and structural and managerial variables of nursing organizations that are described in the Robbins Organizational theory model. The data were collected through self reported questionnaires from 605 nurses working in, and 782 patients hospitalized in, five tertiary hospitals in Seoul. Results showed that according to MANOVA there was a significant difference in nurses job satisfaction and patient satisfaction among the five hospitals. According to cluster analysis of the structural and managerial variables of nursing organizations, the five hospitals were divided into two clusters and there was no significant difference in nurses job satisfaction or patient satisfaction between the two clusters. According to canonical correlation analysis the formalization and centralization of structural variables were shown to be predicting variables for nurses job satisfaction, and the managing job design and managing Change of managerial variables were shown to be predicting variables for nurses job satisfaction.

• Journal of Korean Academy of Nursing
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• v.27 no.2
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• pp.253-263
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• 1997

This second study on the effectiveness of nursing organization was designed to test the relationships between effectiveness of nursing organizations and structural variables that had been significant variables in the first study, the group design variable and the personal characteristic variables that had not been analyszed in the first study based on personal resource productivity model. The data were collected through self-reported questionnaires completed by 605 nurses working in hospitals in seoul and 782 patients being hospitalized in 5 tertiary hospitals in Seoul. The results showed that according to the canonical correlation analysis, the managing job design, nursing delivery system. nurse's age, career. and formalization were revealed as predicting variables of a nurses' job satisfaction and patients satisfaction among the five hospitals. Hospitals in which the team nursing method was used showed a higher score in nurses' job satisfaction and patient satisfaction than in hospitals which used the functional nursing model.

• Journal of Fisheries and Marine Sciences Education
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• v.29 no.2
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• pp.436-446
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• 2017

This study was performed to verify the validity and utility of the Korean Behavior Rating Inventory of Executive Function-Preschool Version(BRIEF-P). The BRIEF-P is one of the most used instruments to measure Executive Function(EF) and a teacher-rating assessment method designed to measure the executive function of preschoolers(age 2-5). A total of 200 preschoolers(104 boys, 96 girls; recruited aged 3 to 5years) participated. Confirmatory factor analysis was carried out to evaluate the model structure. Correlation analysis was done to verify the concurrent validity. In the results, the model fit indexes were good with the five BRIEF-P subscales (that is, inhibit, shift, emotional control, working memory, plan/organize). The internal consistency of the BRIEF-P five subscales were supported. As a results, the Korean Behavior Rating Inventory of Executive Function-Preschool Version(BRIEF-P) was confirmed to be a reliable and valid assessment tool to measure executive function in preschoolers.

• Journal of Digital Convergence
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• v.13 no.11
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• pp.313-320
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• 2015

This study was to explore the impact of organizational characteristics on knowledge sharing of dental hygienist on working for dental clinic or hospital. Data were collected from 349 dental hygienists by structured questionnaires in dental clinics or dental hospitals in Korea. Data was analysed by using SPSS 18.0 program with one-way ANOVA and multiple regressions. This study showed a positive correlation between knowledge sharing and clan culture of organizational culture(t=5.060, p=.000). It was described that knowledge share of dental hygienist has an effect on work performance partially. According to the study, dental organizational forms for knowledge sharing in the dental hygienist is require to maximize the work performance.

• Korean Journal of Remote Sensing
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• v.34 no.4
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• pp.661-670
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• 2018

This study aims to develop a methodology of convolutional neural networks (CNNs) to produce thematic maps from remote sensing data. Optimizing the image size for CNNs was studied, since the size of the image affects to accuracy, working as hyper-parameter. The selected study area is Mt. Ung, located in Dangjin-si, Chungcheongnam-do, South Korea, consisting of both coniferous forest and deciduous forest. Spatial structure analysis and the classification of forest type using CNNs was carried in the study area at a diverse range of scales. As a result of the spatial structure analysis, it was found that the local variance (LV) was high, in the range of 7.65 m to 18.87 m, meaning that the size of objects in the image is likely to be with in this range. As a result of the classification, the image measuring 15.81 m, belonging to the range with highest LV values, had the highest classification accuracy of 85.09%. Also, there was a positive correlation between LV and the accuracy in the range under 15.81 m, which was judged to be the optimal image size. Therefore, the trial and error selection of the optimum image size could be minimized by choosing the result of the spatial structure analysis as the starting point. This study estimated the optimal image size for CNNs using spatial structure analysis and found that this can be used to promote the application of deep-learning in remote sensing.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.9
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• pp.6112-6119
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• 2015

This study attempted to examine the job stress and turnover intentions of physical therapists and to investigate the relationship between these two factors. A total of 309 physical therapists currently working in Gyeonggi-do and Incheon in South Korea were selected as research subjects. The data were collected by a survey using self-administered questionnaires structured from June 10 to June 25, 2015. According to the study results, job stress was highest in job autonomy and lowest in relationship conflict, while the turnover intention score was $2.80{\pm}0.70$. The physical therapists showed higher job stress and turnover intention level with increasing age and working experience, showing a significant positive correlation(p<.05). The turnover intention showed a significant positive correlation with all of the job stress factors. Decreased work motivation showed a significant positive correlation with all of the job stress factors except for job instability(p<.05). In addition, among the factors for the job stress, Job autonomy, Structure and organization, Inappropriate compensation, and Workplace culture turned out to be those affecting their turnover intention. This study confirmed that an increase of job stress among physical therapists can be a risk factor of higher turnover intention, implying a necessity to try to reduce their job stress and turnover intention.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.358-358
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• 2012

The application of BZO (Boron-doped Zinc Oxide) films use as the TCO(Transparent Conductive Oxide) material for display and solar cell industries, where the conductivity of the BZO films plays a critical role for improvement of cell performance. Thin BZO films are deposited on glass substrates by using RF sputter system. Then charging flow rates of O2 gas from zero to 10 sccm, thereby controlling the impurity concentration of BZO. BZO deposited on soda lime glass and RF power was 300 W, frequency was 13.56 MHz, and working pressure was $5.0{\times}10-6$ Torr. The Substrate and glass between distance 200 mm. We measured resistivity, conductivity, mobility by hall measurement system. Optical properties measured by photo voltaic device analysis system. We measured surface build according to oxygen flow rate from XPS (X-ray Photoelectron Spectroscopy) system. The profile of the energy distribution of the electrons emitted from BZO films by the Auger neutralization is measured and rescaled so that Auger self-convolution arises, revealing the detail structure of the valence band. It may be observed coefficient ${\gamma}$ of the secondary electron emission from BZO by using ${\gamma}$-FIB (Gamma-Focused Ion Beam) system. We observed the change in electrical conductivity by correlation of the valence band structure. Therefore one of the key issues in BZO films may be the valence band that detail structure dominates performance of solar cell devices. Demonstrating the secondary electron emission by the Auger neutralization of ions is useful for the determination of the characteristics of BZO films for solar cell and display developments.