• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.113.1-113.1
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• 2011

PEMS (printed electro-mechanical system) is fabricated by means of various printing technologies. Passive and active compo-nents in 2D or 3D such as conducting lines, resistors, capacitors, inductors and TFT(Thin Film Transistor), which are printed withfunctional materials, can be classified in this category. And the issue of PEMS is applied to a R2R process in the manu-facturing process. In many electro-devices, the vacuum process is used as the manufacturing process. However, the vacuum process has a problem, it is difficult to apply to a continuous process such as a R2R(roll to roll) printing process. In this paper, we propose an ESD (electro static deposition) printing process has been used to apply an organic solar cell of thin film forming. ESD is a method of liquid atomization by electrical forces, an electrostatic atomizer sprays micro-drops from the solution injected into the capillary with electrostatic force generated by electric potential of about several tens kV. ESD method is usable in the thin film coating process of organic materials and continuous process as a R2R manufacturing process. Therefore, we experiment the thin films forming of PEDOT:PSS layer and active layer which consist of the P3HT:PCBM. The organic solar cell based on a P3HT/PCBM active layer and a PEDOT:PSS electron blocking layer prepared from ESD method shows solar-to-electrical conversion efficiency of 1.42% at AM 1.5G 1sun light illumination, while 1.86% efficiency is observed when the ESD deposition of P3HT/PCBM is performed on a spin-coated PEDOT:PSS layer.

• Journal of Advanced Navigation Technology
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• v.22 no.5
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• pp.415-419
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• 2018

This paper predicts and measures the C/N ratio of a beacon signal transmitted from geostationary orbit satellite KorSat 5A ($113^{\circ}E$) at a ground station located in Kimpo. Based on the ground stations, we compared the rain attenuation of the zone K of ITU-R and the rain attenuation which analyzed the domestic weather information. In ITU-R, the Korean rainfall characteristics are classified into zone K, but forecasting the rainfall intensity and attenuation of three adjacent cities based on the cumulative rainfall data per minute from 2013 to 2017. The calculation of rainfall path and attenuation is based on ITU-R recommendations. The change of the C/N according to the rainfall amount was confirmed through the 2 week satellite beacon signal C/N measurement. The predicted critical C/N was decreased to 12 dB at $A_{0.3}$. During the experiment, it was confirmed that it decreased up to 8 dB according to the concentrated rainfall.

• Polymer(Korea)
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• v.37 no.1
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• pp.74-79
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• 2013

Polyvinylidene fluoride (PVDF) and its copolymer with hexafluoropropylene (HFP) were successfully prepared from free radical solution polymerizations using diisopropyl peroxidicarbonate (DIPPDC) in the presence of 1,1,2-trichlorotrifluoroethane (R-113). The reactivity ratios of VDF and HFP were estimated as$r_{VDF}=2.06{\pm}0.03$ and $r_{HFP}{\approx}0$. This result indicates that HFP cannot undergo self propagation. The weight-average molecular weight and molecular weight distribution of copolymers were found to decrease with increasing HFP content. The melting temperature of copolymers linearly decreased with the increase of HFP content because of the introduction of HFP. Moreover, no melting peak was observed for the copolymers with high HFP content. The glass transition temperature of copolymers gradually increased with the increase of HFP content due to the restricted flexibility of the polymer chains.

• The Journal of the Convergence on Culture Technology
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• v.7 no.2
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• pp.27-33
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• 2021

The purpose of this study was to investigate the influence of clinical nurses' sleep disorder, organizational support, and health promotion behaviors on professional quality of life. The subjects were 256 nurses working in hospitals in more than 200 and less than 300 beds hospital in B and G cities. The data were collected from September 4, 2017 to September 11, 2017. The collected data were analyzed by frequency analysis t-test, ANOVA, Scheffé test, Pearson's correlation coefficients, and multiple regression analysis using SPSS WIN 20.0. Burnout rate was 28.90± 4.00, burnout was associated with sleep disorder(r=-.321, p<.001), organizational support(r=-.321, p<.001), health promoting behavior(r=-,519 p<.001) showing a negative correlation. The factors affecting burnout were organizational support(β=-.113, p=.045), sleep disorder(β=-.129, p<.040), gender(β=-.131, p=.024), health promotion behaviors(β=-.423, p<.001) and the explanatory power was 32.2%. Based on these results, we aim to provide basic data for the development of various programs that can control burnout of nurses.

• Fire Science and Engineering
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• v.33 no.1
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• pp.113-120
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• 2019

The disaster and safety R&D budget has continued to increase since 2008, but the fire safety R&D budget is a small part. Therefore, successful outcomes that could lead to the economic growth of the fire safety industry have not been achieved. This paper suggests a fire safety R&D budget expansion, reinforcement of R&D capacity, and performance growing plan by analyzing the factors that affect the performance of a fire safety R&D project. Empirical analysis was performed through one-way ANOVA and regression analysis using the statistical program, SPSS statistics 21.0. As a result, this study suggests that the continuous expansion of R&D funds and the securing of excellent trained research manpower will be necessary to obtain qualitatively superior patents and papers.

• Journal of the Korea Convergence Society
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• v.10 no.10
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• pp.33-41
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• 2019

This study aimed to investigate the convergence relationship between kinesiophobia and fear of falling in patients with stroke. A total of 113 patients with stroke participated in this study. Participants underwent inpatient rehabilitation and completed surveys with three different questionnaires including the fall efficacy scale (FES), translated Tampa Scale for Kinesiophobia 13 (TSK-13), and activity-specific balance confidence scale (ABC). TSK-13 and FES showed weak negative correlation (r=-0.226), and TSK-13 and ABC showed moderate negative correlation (r=-0.300). FES had a very strong positive relationship compared with ABC (r=0.838). Faller showed significantly low FES and ABC scores compared with non-faller (p<0.05). These results present that patients with stroke had mild kinesiophobia, and kinesiophobia is related to fear of falling. It is necessary to evaluate kinesiophobia in stroke rehabilitation.

• Journal of Industrial Convergence
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• v.21 no.12
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• pp.113-122
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• 2023

This study investigates the effects of communication ability and interpersonal anxiety on self-esteem before the first clinical practice in nursing students. A survey was administered to third-year nursing students who had yet to begin their clinical practice from May 15 to May 20, 2023. The data were analyzed using descriptive statistics, t-test, ANOVA, Pearson's correlation, multiple regression with the SPSS/WIN26.0 program. The results showed that self-esteem is positively correlated with communication ability(r=.564) and negatively correlated with interpersonal anxiety(r=-.590) and there was a negative correlation between communication skills and interpersonal anxiety(r=-.515). The impact on self-esteem was in the order of interpersonal anxiety (𝛽=-.41) and communication ability(𝛽=.35). In conclusion, the research results showed that the higher the communication ability and the lower the interpersonal anxiety, the more it affects self-esteem. Thus, it is important to develop and implement tailored programs that enhance communication skills and facilitate interpersonal interactions while reducing anxiety for nursing students at different school years and stages.

• Journal of the Korean Applied Science and Technology
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• v.40 no.4
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• pp.890-896
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• 2023

This study aims to examine the relationship between serum folic acid levels and metabolic syndrome. The analysis data were downloaded and used for the 7th 3rd (2018) data of the National Health and Nutrition Survey and in this study, 495 men, 706 women, and a total of 1,201 people were finally analyzed. The data analysis used Chi-square and t-test for the difference in serum folic acid according to general characteristics, Pearson correlation for the relationship between sub-factors of metabolic syndrome, and logistic regression analysis for serum folic acid levels and metabolic syndrome indicators. According to the results of this study, there was a significant negative correlation between serum folic acid levels and waist circumference (r=-0.113, p<0.01), triglyceride (r=-0.086, p<0.05), and HDL-cholesterol (r=0.086, p<0.05) showed a significant positive correlation. As a result of regression analysis, in the case of HDL-cholesterol, the group with normal serum folic acid levels was significantly higher than the group with low (p<0.05). Therefore, through this study, it is proposed to develop appropriate eating habits and health education programs to prevent metabolic syndrome.

• Korean System Dynamics Review
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• v.13 no.1
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• pp.113-131
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• 2012

Applying social network analysis techniques, this study examines complex system characteristics of industry-university joint research R&D networks. In specific, it focuses on whether these R&D networks comply with the power law, whose system typically presents the-rich-get-richer and the-poor-get-poor patterns. The basic data come from 7,751 industry-university joint research projects, all of which were carried out by Daejeon, Chungbuk, and Chungnam-based universities from January 2005 to October 2008. The empirical results reveal that the R&D networks abide by the power law. That is, a handful of business units and universities command an overwhelming majority in the joint links, indicating positive feedback dominance within the system.

• Journal of Technology Innovation
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• v.15 no.1
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• pp.87-113
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• 2007

For the realization of the national self-defense, the trend of the defense R&D projects becomes global and diverse with the increase of their budget. Thus, for the effective execution of the budget and the successful performance of the projects, the importance of selection, management and evaluation of the R&D projects is emphasized. This study suggests the applicability of a meta-evaluation model for the realization of the successful defense R&D project evaluation system. This study focused on the development of the meta-evaluation model design which can be applicable to the national defense R&D projects. Using the proposed meta-evaluation model, we propose a technique to enhance the fairness and the reliability of the national defense R&D projects evaluation system.