• Communications for Statistical Applications and Methods
• /
• v.12 no.1
• /
• pp.241-252
• /
• 2005

In this study we suggest that the spatial correlation structure of the brain fMRI data be used to characterize the functional connectivity of the brain. For some concussion and recovery data, we examine how the correlation structure changes from one step to another in the data analyses, which will allow us to see the effect of each analysis to the spatial correlation or the functional connectivity of the brain. This will lead us to spot the processes which cause significant changes in the spatial correlation structure of the brain. We discuss whether or not we can decompose correlation matrices in terms of its causes of variations in the data.

• Carbon letters
• /
• v.9 no.2
• /
• pp.137-144
• /
• 2008

The commercial activated carbons are typically prepared by activation from coconut shell char or coal char containing lots of inorganic impurities. They also have pore structure and pore size distribution depending on nanostructure of precursor materials. In this study, two types of commercial activated carbons were applied for EDLC electrode by removing impurities with acid treatments, and controlling pore size distribution and contents of functional group with heat treatment. The effect of the surface functional groups on electrochemical performance of the activated carbon electrodes was investigated. The initial gravimetric and volumetric capacitance of coconut based activated carbon electrode which was acid treated by $HNO_3$ and then heat treated at $800^{\circ}C$ were 90 F/g and 42 F/cc respectively showing 94% of charge-discharge efficiency. Such a good electrochemical performance can be possibly applied to the medium capacitance of EDLC.

• The korean journal of orthodontics
• /
• v.23 no.4 s.43
• /
• pp.447-454
• /
• 1993

Patient with skeletal class II relationship was treated with L-ARS. L-ARS is fixed functional appliance that could be effective in children and adolescent patient who don't wear activator. The following results were obtained ; 1) Growth of Mandible was stimulated and overjet was decreased, therefore coupling of anterior teeth was established with L-ARS which is fixed functional appliance. 2) These changes were accomplished with Mandibular skeletal growth with no effect on the Maxilla. 3) L-ARS was especially effective on patient who deny to wear the removable functional appliance.

• Carbon letters
• /
• v.1 no.3_4
• /
• pp.138-142
• /
• 2001

The effect of electrochemical surface treatments in KOH chemical solution on microstructures of carbon blacks was investigated in terms of surface functional values and XRD measurements. And their mechanical interfacial properties of the carbon blacks/rubber composites were studied by the composite tearing energy ($G_{IIIC}$). It was found that the development of basic-surface functional groups lead to the significant physical changes of carbon blacks, such as, decrease of the interlayer spacing ($d_{002}$), increase of the crystalline size along c-axis ($L_c$), and increase of degree of crystalline (${\chi}_c$). This treatment is possibly suitable for carbon blacks to be incorporated in a hydrocarbon rubber matrix, resulting in improving the hardness and tearing energy of the resulting composites.

• The Mathematical Education
• /
• v.45 no.3 s.114
• /
• pp.263-273
• /
• 2006

The purpose of this paper is to research the factors and the effects of immediacy in mathematics teaching and learning and mathematical problem solving. The factors of immediacy are visualization, functional fixedness and representatives. In special, students can apprehend immediately the clues and solution using the visual representation because of its properties of finiteness and concreteness. But the errors sometimes originate from visual representation which come from limitation of the visual representation. It suggests that students have to know conceptual meaning of the visual representation when they use the visual representation. And this phenomenon is the same in functional fixedness and representatives which are the factors of immediacy The methods which overcome the errors of immediacy is that problem solvers notice the limitation of the factors of immediacy and develop the meta-cognitive ability. And it means we have to emphasize the logic and the intuition in mathematical teaching and learning. Clearly, we can't solve all mathematical problems using only either the logic or the intuition.

• Proceedings of the IEEK Conference
• /
• 2001.06b
• /
• pp.121-124
• /
• 2001

This paper proposed resource allocation algorithm for the minimum switching activity of functional unit in high level synthesis process as like DSP which is circuit to give many functional unit. The resource allocation method after scheduling use the power function calculating average hamming distance and switching activity of the between two input. First of all, the switching activity is calculated by the input value after calculating the average hamming distance between operation. In this paper, the proposed method though high If level simulation find switching activity in circuit each functional unit exchange for binary sequence length and value bit are logic one value. To use the switching activity find the allocation with minimal power consumption, the proposed method visits all control steps one by one and determines the allocation with minimal power consumption at each control step. As the existing method, the execution time can be fast according to use the number of operator and max control step. And it is the reduction effect from 6% to 8%.

• Fibers and Polymers
• /
• v.4 no.4
• /
• pp.215-221
• /
• 2003

A vertical skin model with two detachable environmental chambers was developed to simulate a Human-Clothing-Environment system and to evaluate heat and moisture transport properties of textile materials under severe conditions and during transient states. The construction of the system was described and data reproducibility and accuracy of the instrument were verified by using PEG treated nonwovens. Also advantages over a traditional static type experiment were demonstrated based on a series of experiments.

• Journal of the Korean Society of Costume
• /
• v.58 no.2
• /
• pp.1-14
• /
• 2008

This study aimed to investigate the associations between clothing consumption values and the ambivalent clothing consuming behavior of young female adults. To explain the ambivalent consuming behavior prevailing in the contemporary fashion market, five dimensional consumption values proposed by Sheth(1991) were adopted as explanatory factors, and fashion leadership and spending were included as moderating factors. Data collecting using written survey instrument yielded one hundred and seventy two complete responses from female consumers aged between 20 and 39. Factor analysis on clothing consumption values resulted in five dimensional structures of consumption values for the sample: expressive, epistemic, functional, social, and fashionable values. Among these, expressive, functional, and social values significantly affected ambivalent consuming behavior. The effect of expressive value was strong regardless of fashion innovativeness, opinion-leadership, and monthly income of consumers, however, the effects of epistemic, functional, and social values were changed depending on the moderating factors.

• Journal of Information Display
• /
• v.11 no.3
• /
• pp.95-99
• /
• 2010

A series of new dielectric polymers with phenyl, epoxy, and carboxylicacid functional groups was prepared via free-radical polymerization. The effect of such dielectric polymers with various functional groups on the performance of OTFT was investigated. The nonpolar groups of terpolymer made the surface of the dielectric layer more hydrophobic and improved the crystal growth of pentacene on the gate insulator, resulting in higher mobility. By controlling the functional group, the electric characteristics of OTFT performance was varied, with $0.00017-0.15\;cm^2/V{\cdot}s$ mobility.

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