• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.214.1-214.1
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• 2011

In this work, the electrochemical properties of the surface treated multi-walled carbon nanotubes (MWNTs) are investigated for supercapacitors. Nitrogen- and oxygen functional groups containing MWNTs are prepared by nitrogen precursors and acidic treatment, respectively. The surface properties of the MWNTs are confirmed by X-ray photoelectron spectroscopy (XPS) and Zeta-potential measurements. The electrochemical properties of the MWNTs are investigated by cyclic voltammetry, impedance spectra, and charge-discharge cycling performance in 1 M $H_2SO_4$ at room temperature. As a result, these functionalized MWNTs lead to an increase in the specific capacitance as compared with the pristine MWNTs. It proposes that the pyridinic and pyridinic-N-oxides nitrogen species influence on the specific capacitance due to their positive charges, and thus an improved electron transfer at high current loads, since they are the most important functional groups affecting capacitive behaviors.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.94.2-94.2
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• 2011

In this work, multi-functional groups, i.e., nitrogen and oxygen, contained microporous carbons (MF-MCs) were prepared by the one step carbonization of the poly(vinylidene chloride-co-acrylonitrile-co-methyl methacryalte) (PVDC-AN-MMA) without activation. The electrochemical performance of MF-MCs was investigated as a function of carbonization temperature. It was found that MF-MCs had a high specific surface area over $800m^2/g$ without additional activation, resulting from the micropore's formation by the release of chlorine groups. In addition, although functional groups decreased, specific surface area was increased with increasing carbonization temperature, leading to the enhanced electrochemical performance. The pore size of the carbon distributed mainly in small micropore of 1.5 to 2 nm, which was idal for aqueous electrolyte. Indeed, the unique microstructure features, i.e. high specific surface area and optimized pore size provided high energy storage capability of MF-MCs. These results indicated that the microporous features of MF-MCs lead to feasible electron transfer during charge/discharge duration and the presence of nitrogen and oxygen groups on the MF-MCs electrode led to a pseudocapacitive reaction.

• Carbon letters
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• v.11 no.4
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• pp.298-303
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• 2010

A method of functionalization of multi-walled carbon nanotube (MWNT) at room temperature using dry ozone gas is described. The resulting MWNT were characterized by Fourier transform infrared, x-ray photoelectron spectroscopy, and scanning electron microscopy. Combined to these analyses and solubility in liquids, it could be concluded that the dry ozone gas exposure introduces polar functional groups such as carboxylic groups to MWNT similar to acidic modification of MWNT. Particularly, the stable dispersion of MWNT in water after ozone treatment above a critical level could be obtained, implying potential bio-application. The hydrophilic functional groups on the MWNT introduced by ozone oxidation were helpful in improving the interaction with functional groups in PA6 such as $-NH_2$ and -CONH- resulting in improved mechanical properties.

• Bulletin of the Korean Chemical Society
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• v.31 no.6
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• pp.1596-1600
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• 2010

Surface functionalization of multi-walled carbon nanotubes (MWNTs) was carried out by means of acid treatment. The presence of oxygen functional groups on the surface of acid-treated MWNTs was confirmed with the aid of Fourier transform infrared spectroscopy and X-ray spectroscopy. In addition, carboxylic groups generally formed on the surface of acid-treated MWNTs, and the dispersion was increased by the duration of the acid treatment. The zeta-potential indicated the surface charge transfer and the dispersion of MWMTs. Morphological characteristics of acid-treated MWNTs were also observed using a transmission electron microscopy, X-ray diffraction, and Raman analysis, which was revealed the significantly unchanged morphologies of MWNTs by acid treatment. The hydrogen adsorption capacity of the MWNTs was evaluated by means of adsorption isotherms at 77 K/1 atm. The hydrogen storage capacity was dependent upon the acid treatment conditions and the formation of oxygen functional groups on the MWNT surfaces. The latter have an important effect on the hydrogen storage capacity.

• Fashion & Textile Research Journal
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• v.5 no.1
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• pp.77-81
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• 2003

The purpose of this study was to investigate the effect of multi-functional fabric on EEG and growth hormone (GH) during sleep and quality of sleep with the 9 young female athletes. The subjects participated in separated experimental procedure; sleeping in multi-functional fabric wear (experimental group) and cotton wear (control group) for 450min. During the night (22:00-05:30), we recorded the changes of nocturnal polysomnographic sleep recording and GH were measured every 60min. The results show that there are significant differences in percentage of stage 1, 2 and slow wave sleep (SWS) between two groups(S1, p<.05; S2, SWS, p<.01). The SWS percentage of experimental group is 1.89 times higher than control group. The changes of GH secretion varied depending on two experimental procedures. The peak of GH secretion in experimental group is more than controls by 2.4time (p<.001). The quality of sleep in experimetal group is significantly higher than control (p<.01). These results suggest muti-functional fabric wear is effective in inducing the deep sleep and increasing GH and quality of sleep.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.29 no.3
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• pp.13-22
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• 2023

Background: The purpose of this study was to investigate the effects of functional massage and stretching, applied to the elbow and shoulder joints, on pain, tenderness threshold, and grip strength. Methods: A total of 29 individuals were assigned to a single site (n=15) or multiple sites (n=14). Pain measured through the visual analogue scale (VAS), tenderness threshold (TTH), and grip strength (GI) were measured before and four weeks after the intervention. Results: After four weeks of treatment, visual analogue scale significantly decreased in both groups (p<.05), and the tenderness threshold and grip strength significantly increased in both groups (p<.05). There was also a significant difference between the two groups (p<.05). Conclusion: The reduction of visual analogue scale and the increase in the tenderness threshold and grip strength were more significant in the multi-site treatment group than in the single-site treatment group.

• Journal of Fashion Business
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• v.18 no.4
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• pp.153-167
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• 2014

In this study, changes in the timing of puberty physicality and mentality and beauty characteristics of high school students were characterized for high school students and the general high school population in order to distinguish between interest and beauty and beauty products and beauty behavior for comparative analysis. First, for beauty characteristics of high school students and the general high school population, differences in beauty action and beauty characteristics of high school students were higher than this beauty behavior. Secondly, for the high school students and high school beauty characteristics of general high school population for beauty and beauty products, the difference between interest and multi-functional beauty products that characterize high school students has beauty and beauty products with multi-functional beauty products interest being high. Third, high school students and high school beauty characterize the general high school population of beauty is different from behaviors on its factors with common factors including the psychological gratification 'for reasons of appearance management looks for reasons that do not' have time to manage the response. Two groups of factors that characterize the differences in appearance and beauty as areason to manage high school students interested in the 'style' order, high school students do not manage reasons for lack of interest in the 'general' as a response. Beauty characteristics of high school students in the beauty, beauty products, and products demonstrated a multi-functional information gathering with lots of attention, and much ability can have an active beauty behavior. The general high school population lacks the ability to gather information in accordance with interested beauty behavior being passive. The two groups and beauty behavior patterns of consumption could see that a difference occurred.

• Proceedings of the Korean Information Science Society Conference
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• 2012.06c
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• pp.413-414
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• 2012

Currently the amount and variety of data being generated is unprecedented and dramatically changes the way individuals, groups, and societies act and make decisions. Visualization is one of the most important commonly used methods of analyzing and interpreting digital assets and the interactive environments are necessary to enable effective discovery and decision making. In this paper we present several examples and approaches to scalable functional representations and interactive visualization and analysis. The functional representations provide us unified, compact, continuous, multi-scale, and compressed representations in the data domain.

• Journal of the Korean Chemical Society
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• v.54 no.1
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• pp.93-98
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• 2010

In this work, the electrochemical properties of surface treated multi-walled carbon nanotubes (MWNTs) were studied. Nitrogen and oxygen functional groups of the MWNTs were introduced by urea and acidic treatment, respectively. The surface functional groups of the MWNTs were confirmed by X-ray photoelectron spectroscopy (XPS) measurements and zeta-potential method. The characteristics of $N_2$ adsorption isotherm at 77 K, specific surface area, and total pore volumes were investigated by BET eqaution, BJH method and t-plot method. Electrochemical properties of the functionalized MWNTs were accumulated by cyclic voltammetry at the scan rates of 50 $mVs^{-1}$ and 100 $mVs^{-1}$ in 1M $H_2SO_4$ as electrolytes. As a result, the functionalized MWNTs led to an increase of capacitance as compared with pristine MWNTs. It was found that the increase of capacitance for urea treated MWNTs was attributed to the increase in density of surface functional groups, resulting in improving the wettability between electrode materials and charge species.

• Korean Journal of Social Welfare Studies
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• v.44 no.2
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• pp.327-358
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• 2013

This study aimed to analyze the trajectories of cognitive function and functional disability, and to identify the impacts of socio-demographic factors on the two variables. Based on the assumption that there are differences according to the progress of cognitive impairment, it focused on examining the differences in trajectories of cognitive function and functional disability between two groups: dementia conversion group and dementia non-conversion group among cognitively normal older adults. This study was conducted based on the data from a 3-wave panel study of a sample of 966 Yeoncheon elderly cohort aged 65 and over between 1997 and 2003. Latent growth curve model and multi-group structural equation modeling were used to examine the hypothesis. Results revealed that dementia conversion group exhibited faster rate of cognitive decline as well as lower initial cognitive level. Difference between two groups was not significant in the initial level of functional disability, yet dementia conversion group showed greater degree of deterioration in the functional disability over time than dementia non-conversion group did. In terms of the influence of socio-demographic factors on cognitive function and functional disability, the cognitive decline was more drastic in the female group, whereas functional decline was more apparent for the male group. The level of education in early life had a strong impact on the cognitive function in later life. Based on these findings, practical implication for high risk groups in cognitive function and functional disability were discussed.