• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.133.1-133.1
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• 2010

In this work, carbon black(CBs)-embed multi-walled carbon nanotubes (MWNTs) as conductive fillers for activated carbon(ACs)-based electrodes for supercapacitor were prepared by chemical reduction of oxidized MWNTs and CBs. The effect of CBs-MWNT composites on electrochemical performances of ACs-based electrodes were investigated as a function of CB-MWNT ratio. It was found that CBs-MWNTs composites were formed by the reduction reaction of the functional groups of oxidized MWNTs and CBs. It was resulted in the conjugation of CBs onto the MWNT having high surface area and aspect ratio, leading to the enhanced electrical properties of MWNTs. The electrochemical performances, such as current density, charge-discharge, and specific capacitance of the ACs/CBs-MWNT electrodes were higher than that of ACs/MWNTs and conventional ACs/CB electrodes, which was attributed to the synergistic effect of CBs-MWNTs as a conductive filler.

• Carbon letters
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• v.8 no.4
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• pp.292-298
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• 2007

In order to investigate functional groups on the surface of Multi-walled Carbon Nanotubes (MWCNTs) induced by oxyfluorination, XPS (X-ray photoelectron spectroscopy) analysis was carried out. All core level spectra of MWCNTs were deconvoluted to several Pseudo-Voigt functions (sum of Gaussian-Lorentzian functions). Both O1s and F1s binding energy of oxyfluorinated MWCNTs shifted high value as increment of fluorine mixing ratio. The carbon-fluorine covalent bonding concentration increased as increment of fluorine mixing ratio. The shape and intensity of OF10-MWCNTs are similar with those of as-received MWCNTs. However, the intensity and binding energies of main peak position of OF20-MWCNTs and OF30-MWCNTs were dramatically increased by oxyfluorination.

• Carbon letters
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• v.13 no.1
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• pp.29-33
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• 2012

A novel strategy for the simultaneous reduction and functionalization of graphene oxide (G-O) was developed using polyallylamine hydrochloride (PAAH) as a multi-functional agent. The G-O functionalization by PAAH was carried out under basic conditions to catalyze the epoxide ring opening reaction of G-O with abundant amine groups of PAAH. We found that G-O was not only functionalized with PAAH but also reduced under the reaction condition. Moreover, the synthesized PAAH-functionalized G-O sheets were soluble in water and applicable to the synthesis of nanocomposites with gold nanoparticles.

• Journal of the Korean Chemical Society
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• v.66 no.4
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• pp.269-277
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• 2022

In recent years, carbon-based catalysts have become a research hotspot in environmental governance applications. Carbon-based catalysts have large surface areas, porous structures, multi-surface functional groups and excellent electron transfer capabilities, and can synergistically exhibit adsorption and catalytic performance. This article reviews the research progress of carbon-based catalysts in environmental governance, mainly including its application in wastewater treatment, exhaust gas purification and soil remediation. In view of the current difficulties in the research of carbon-based catalysts, the development prospects are proposed. We hope that this review will provide convenience for new entrants and researchers intending to employ carbon-based catalysts for the remediation of contaminated environment.

• Korean Journal of Psychosomatic Medicine
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• v.29 no.1
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• pp.58-66
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• 2021

Objectives : The purpose of this study is to compare the psychosocial characteristics of patients diagnosed with functional gastrointestinal disorder (FGID) by classifying them into irritable bowel syndrome (IBS), functional dyspepsia (FD), functional constipation (FC), functional heartburn (FH) groups, and overlap group (two or more functional diseases) and to examine the factors associated with the quality of life (QoL) of patients with FGID. Methods : A total of 144 patients who were diagnosed with FGID were selected as the subjects. The demographical factors were investigated; Korean-Beck Depression Inventory-II (K-BDI-II), Korean-Beck Anxiety Inventory (K-BAI), Korean version of Childhood Trauma Questionnaire (K-CTQ), Multi-dimensional Scale of Perceived Social Support (MSPSS), Korean Version of Connor-Davidson Resilience Scale (K-CD-RISC), and World Health Organization Quality of Life Assessment Instrument Brief Form (WHOQOL-BREF) were used to evaluate the psychosocial factors. Results : TThe overlap group had a significantly higher K-BDI-II score (F=11.09, p<0.001) and K-BAI score (F=8.93, p<0.001) compared to other groups. In childhood trauma, the IBS patients had a difference in emotional neglect (F=2.54, p=0.04) than the FD patients. The QoL of FGID patients had a negative correlation with depression (r=-0.196, p<0.01), anxiety (r=-0.235, p<0.01), and childhood trauma (r=-0.222, p<0.01), and a positive correlation with social support (r=0.512, p<0.01) and resilience (r=0.581, p<0.01). Conclusions : Overlap group had a higher level of depression and anxiety, and the IBS patient group had a higher level of emotional neglect than the FD patient group in terms of childhood trauma.

• The Journal of the Korea Contents Association
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• v.14 no.2
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• pp.103-112
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• 2014

With the development of the society, people's thought and the way of life is changing. The change of the traditional values and marriage lead to the increase of the "singles" groups in modern society. The "singles" group's behaviors, living environment, and consumption have become a social focus. With the emergence of the "singles", traditional furniture already can't meet the demand, so personalized furniture should be developed for the "singles". This study based on background and consumption psychology of the "singles", analyzed the consumption characteristics and preferences of the "singles". It studied the furniture demand of the "singles", and analyzed the existing unmarried person's residential form, types and characteristics of the furniture, and also analyzed the existing furniture using by the "singles" with SWOT, made a more systematic study for finding the advantages and disadvantages of existing the "singles" group's furniture. Then, combined with the unmarried person's furniture needs, living forms, the advantages and disadvantages of the "singles" furniture, etc., made the multi-functional furniture design concept for the "singles". This concept as a design direction, which would make out more suitable furniture be in keeping with the "singles" group's characteristics and requirements. Finally through the concept of multi-functional and folding raise the utilization ratio of narrow space of the living environment.

• The Journal of the Korea Contents Association
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• v.17 no.12
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• pp.447-460
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• 2017

The purpose of this study is to investigate the factors affecting consumer resistance of smart watches, focusing on consumer groups. SPSS 19.0 was used to conduct a descriptive analysis and multi regression analysis of the data. This study is based on the questionnaire data of 407 consumers. The results of this study are as follows. First, the relative advantage was identified as a factor in reducing consumer resistance across all gender and age groups. Second, complexity has been identified as a factor that increases the consumer resistance of female consumers, and consumer groups in their 20s and 40s. Third, esthetics was found to reduce consumer resistance in men, women, and the consumer group in their 20s. Fourth, subjective norms were identified as a factor reducing consumer resistance in women and in consumer groups in their 20s and 30s. Fifth, the risk of privacy was identified as a factor in increasing consumer resistance in men and the consumer group in their 40s. The results of this study can be helpful to understand consumer resistance to smartwatches.

• Journal of Korea Game Society
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• v.9 no.3
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• pp.23-33
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• 2009

This study aims to uncover the gamers' cognitive process during the gameplay and explore the differences between groups in the gamers' playing behavior according to their expertise: experts, intermediate players, and novices. To this end, the empirical experiment was conducted in 'World of Warcraft' game which is a good representative of MMO(Massively Multi-player Online) game currently. Verbal protocol and action protocol collected from the empirical experiment were analyzed according to the gamers' expertise. As a result of this study, we found that the different behavior patterns result from standardizing pattern of their actions for experts and forming the learning curves and the specific patterns of action for intermediate game players and novices. While three functional-actions as a collection action concentrates on the early stage of the game for experts, the novices' behavior pattern dispersedly appeared in all seven functional-action, such as search, combat, three type collections, avoid, and communication in the whole gameplay. This study represents the consistency and the difference derived from the comparison analysis between groups according to the expertise. This study is concluded with key implications to support game design guidelines according to experts, intermediate players, and novices. Consequently, the result of this study provides the basic to the development of MMO content for game novices.

• Tuberculosis and Respiratory Diseases
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• v.70 no.3
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• pp.224-234
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• 2011

Background: Little data is available regarding hospitalized patients with nursing home-acquired pneumonia (NHAP). This is unfortunate because there is an increasing number of elderly persons who are living in nursing homes in Korea. The aim of this study was to compare clinical characteristics and treatment responses of NHAP with community-acquired pneumonia (CAP). Methods: Patients with pneumonia who were admitted from eight nursing homes or from their own homes were enrolled between May 2007 and April 2009. Their clinical characteristics and treatment responses were reviewed retrospectively, and differences between the two groups were analyzed. Results: Of 110 Patients with pneumonia, 66 (60%) were from nursing homes and their median age was 84. In the NHAP group, functional performance status was significantly poorer, classical symptoms of pneumonia were less severe, and multi-lobe involvement (on chest radiographs) was more frequent than in the CAP group. Patients with NHAP more frequently showed lymphocytopenia, anemia, hypoalbuminemia, hypoxemia, and elevated blood urea nitrogen on admission. The mean CURB-65 score was 2.2 in the NHAP group, higher than 1.7 in the CAP group (p=0.004), and multi-drug resistant pathogens were also highly identified in NHAP group (39% vs. 10%, p=0.036). The mean duration of antibiotic therapy was greater for the NHAP (12.6 days) than for the CAP group (6.6 days) (p<0.001). The mortality rate was 23% in NHAP group, which was significantly higher than 5% in the CAP group (p=0.014). Conclusion: NHAP should be more intensively investigated because of the higher frequency of multi-drug resistant pathogens and mortality than the CAP.

• Korean Chemical Engineering Research
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• v.46 no.1
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• pp.118-123
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• 2008

In the present study, the effect of oxyfluorination treatment on multi-walled nanotubes (MWNTs) supports was investigated by analyzing surface functional groups. The surface characteristics were determined by Fourier transformed-infrared (FT-IR) and X-ray photoelectron spectroscopy (XPS). After the deposition of platinum nanoparticles on the above treated carbon supports, a crystalline size and a loading level had been investigated. Electrochemical properties of the treated MWNTs-supported Pt (Pt/MWNTs) catalysts were analyzed by current-voltage curve measurements. From the results of surface analysis, an oxygen and fluorine-containing functional group had been introduced to the surface of carbon supports. The oxygen and fluorine contents were the highest value at the treatment of 100 temperature. The Pt/100-MWNTs showed the smallest particle crystalline size of 3.5 nm and the highest loading level of 9.4% at the treatment of 100 temperature. However, the sample treated at the higher temperature showed the larger crystalline size and the lower loading level. This indicated that the crystalline size and the loading level could be controlled by changing the temperature of oxyfluorination treatment. Accordingly, an electrochemical activity was enhanced by increasing the temperature of treatment upto 100, and then decreased in the case of 200 and 300. The highest specific current density of 120 mA/mg had been obtained in the case of Pt/100-MWNTs.