• The Journal of the Korea Contents Association
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• v.15 no.12
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• pp.640-649
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• 2015

This study aims to investigate mediating effect of teenagers' spirituality on the relationship between Irrational Beliefs and self-esteem. For research, questionnaires were distributed to 500 teenagers aged 14 to 19. And data were collected from 419 persons. The average age of subjects was 15.8. The collected data verify by structural equation model. As a result, it was shown that the first research model was not good. Hence, according to the results of modifying the model after referring to model modification index, the first modified model showed ${\chi}2=222.527$, df=83,p<.000, CFI=.975, TLI=.968, NFI=.961 and RMSEA=.061. Therefore, it was shown that the model was suitable. According to the results of analyzing the effect of model at this point, it was shown that the direct effect which unreasonable beliefs had on self-esteem was .02, and indirect effect through the mediation of spirituality was .30. Hence, it was verified that spirituality mediated the effect which unreasonable beliefs had on self-esteem. When this is considered, it is thought that, if the level of spirituality is improved, the negative effect which teenagers' unreasonable beliefs had on self-esteem will decrease, though the unreasonable beliefs have a negative effect on self-esteem.

• Journal of the Korean Ceramic Society
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• v.41 no.1
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• pp.86-91
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• 2004

$LiCoO_2$ cathode powders with round particle shaped and nano grain sized of 70-300nm were synthesized by a mechanochemical method. The surface of Li-Co precursor prepared by freeze drying method was modified by $K_2SO_4$ coating and ball milling was used for the coating process. The precursor was crystallized to high temperature form of $LiCoO_2$ at $800^{\circ}C$ and the grain growth was inhibited by the $K_2SO_4$ coating effect. The $K_2SO_4$ coating was not decomposed at $800^{\circ}C$ and prevented the contact in the Li-Co precursor particles. The nano-sized $LiCoO_2$ powder had tetragonal phase and it affected the Li diffusion through the surface of particles. It means that the anode materials for hight performance battery should be satisfied not only small particle size but phase contol on the surface of particles. In this study, the powder characteristics and rate capabilities were compared with a commercial powder and the nano-sized $LiCoO_2$ powder fabricated by the mechanochemical method. And the crucial factor which affects on battery performance was also examined.

• Korean Journal of Materials Research
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• v.11 no.5
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• pp.345-353
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• 2001

The present study was carried out to investigate the effect of zirconium addition to $Al_3$Nb intermetallic on the crystal structural modification and microstructural characterization of $Al_3$Nb intermetallic. Elemental Al, Nb, Zr powders and arc melted $Al_3$Nb and $Al_3$Zr intermetallic mixed powders were used as starting materials. MA was carried out in an attritor rotated with 300 rpm for 20 hours. The behavior of MA between two starting materials was some-what different in which the value of internal strain of the elemental powders was higher than that of the intermetallic powder. The intermetallic powder was much more disintegrated during the MA processing. In the case of the elemental powders, AlNb$_2$ phase were transformed to Al(Nb.Zr)$_2$ as a result of ternary addition of Zr element. With the successive heat treatment at 873K for 2 hours, the Al(Nb.Zr)$_2$ phase was transformed to more stable $Al_3$(Nb.Zr) phase. This transformation was clearly confirmed by the identification of X-ray peak position shift. On the other hand, in the carte of the intermetallic powder, there was no evidence of phase transformation to other ternary intermetallic compounds or amorphous phases, even in the case of additional heat treatment. However, nano-sized intermetallic with $Al_3$Nb and $Al_3$Zr were just well distributed instead of phase transformation.

• Journal of Life Science
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• v.24 no.8
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• pp.915-926
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• 2014

The ribosome is a protein synthesizing machinery and a ribonucleoprotein complex that consists of three ribosomal RNAs (23S, 16S and 5S) and 54 ribosomal proteins in bacteria. In the course of ribosome assembly, ribosomal proteins (r-protein) and rRNAs are modified, the r-proteins bind to rRNAs to form ribonucleoprotein complexes which are folded into mature ribosomal subunits. In this process, a number of non-ribosomal trans-acting factors organize the assembly process of the components. Those factors include GTP- and ATP-binding proteins, rRNA and r-protein modification enzymes, chaperones, and RNA helicases. During ribosome biogenesis, they participate in the modifications of ribosomal proteins and RNAs, and the assemblies of ribosomal proteins with rRNAs. Ribosomes can be assembled from a discrete set of components in vitro, and it is notable that in vivo ribosome assembly is much faster than in vitro ribosome assembly. This suggests that non-ribosomal ribosome assembly factors help to overcome several kinetic traps in ribosome biogenesis process. In spite of accumulation of genetic, structural, and biochemical data, not only the entire procedure of bacterial ribosome synthesis but also most of roles of ribosome assembly factors remain elusive. Here, we review ribosome assembly factors involved in the ribosome maturation of Escherichia coli, and summarize the contributions of several ribosome assembly factors which associate with 50S and 30S ribosomal subunits, respectively.

• Journal of the Korean Chemical Society
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• v.57 no.1
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• pp.147-158
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• 2013

This study is to search an optimal model on causal relationships of the motivations to learn and motivation strategy in chemistry education. The participants in this study are consisted of G and I high schools students (487) in Gwangju. They all answered to the questionnaire. Model I is hypothesized to be path model of the mediation between 'self-efficacy, achievement need, and entity theory of intelligence' and 'learning strategy and self-handicapping tendency of motivation strategy' by goal orientation to explore variables of study effecting the motivation strategy. And Model II is hypothesized path model of the mediation between goal orientation and 'learning strategy and self-handicapping tendency' by 'self-efficacy, achievement need, and entity theory' to explore variables of study effecting the motivation strategy. Based on these models, structural equation modeling techniques are used to evaluate for the path model among goal orientation(learning, performance approach, and performance approach goal orientation), self-efficacy, achievement need, entity theory of intelligence, self-handicapping tendency, and learning strategy in chemistry education. As the results, Model II is considered. Goodness-of-fit indexes of this model related modification models are identified and analyzed in phases. And this model is accomplished by correcting the model the fifth time to enhance goodness-of-fit indexes. In this optimal model II-5 (Fig. 3) on causal relationships of the motivations to learn and learning strategy (p

• Journal of Korean Society of Forest Science
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• v.99 no.4
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• pp.517-527
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• 2010

The purpose of this study was to investigate the causal relationship among perceived value, satisfaction and revisit intention for visitors of the Korea National Arboretum. Three hundred respondents were selected by quota sampling, and well-known measurement scales utilized in marketing field were adopted in order to measure three variables with some modification to apply for arboretum visitors. Results of structural equation model showed that perceived value affected visitors' satisfaction, which in turn influenced revisit intention. Specifically, "emotional value" had the most significant influence on satisfaction, followed by "value for money" and "novelty value"; however, "social value" was not an influential construct. Based on calibration results, several strategies were suggested for the effective management. Authors advised that (a)improvement of measurement scale of value, (b)inclusion of self-congruity as antecedent variable to satisfaction, (c)changing revisit intention to word-of-mouth communication as a post-purchase behavioral intention, and (d)implementation of market segmentation should be considered for future research.

• Applied Microscopy
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• v.37 no.2
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• pp.73-82
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• 2007

The antennae of millipedes have a prominent function in detecting various types of environmental stimuli. The structural modification of the antennae is closely associated with the degree of sense recognition. Here we study functional morphology of the antennae of the millipede Cawjeekelia pyongana using field emission scanning electron microscope (FESEM). The antennae generally include eight segments, called articles. On the surface of the antennae, there are a variety of sensory receptors which include olfactory and mechanical receptors. We could identify four different types of antennal sensory organs in C. pyongana as follows: apical cone (Ac), trichoid sensilla (Ts), chaetiform sensilla (Cs) and basiconic sensilla (Bs). The most prominent of which is four APs at the 8th article. Both of the Is and the Cs are abundantly observed almost all of the antennal segments. They are long and strong bristles with longitudinal grooves acuminating toward the tip. The Bs is further divided into three subtypes: large basiconic sensilla $(Bs_1)$, small basiconic sensilla $(Bs_2)$ and spiniform basiconic sensilla $(Bs_3)$. The $Bs_1$ is located at the 5th and 6th articles, while the $Bs_2$ and $Bs_3$ can be seen at the 5th and at the 7th article, respectively.

• Journal of Korean Society of Steel Construction
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• v.17 no.4 s.77
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• pp.419-429
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• 2005

The objective of this study is to clarify the structural features of members consisting of a connection, as part of the previous study on the CFT column-to-beam tensile connection with a combined cross diaphragm. This connection has the following merits: it evenly distributes the stress on the beam flange and the diaphragm and reduces the stress concentration by improving the stress transfer route and restraining the abrupt deformation of the diaphragm. Finite element analysis was performed to find out the stress transfer through the sleeve, which is an important member of the connection with a combined cross diaphragm. The length and thickness of the sleeve were used as variables for the analysis. The analysis results showed that the length and thickness of the sleeve did not influence the capacity of the connection and played the role of a medium for the transfer of the stress from the diaphragm to the filled concrete. It was proposed that the appropriate length of the sleeve have the same value as the diameter of the sleeve and that the appropriate ratio of the sleeve diameter to the sleeve thickness be 20. Two equations for the evaluation of the load carrying the capacity of the connection were also proposed through the modification of the evaluation equation suggested in the previous study.

• Membrane Journal
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• v.30 no.2
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• pp.97-110
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• 2020

CO₂ capture and storage (CCS) is one of the promising technologies that can mitigate ever-growing emission of anthropogenic carbon dioxide and resultant climate change. Among them, chemical looping combustion (CLC) and calcium looping (CaL) are getting increasing attention recently as the prospective alternatives to the existing amine scrubbing. Both methods use metal oxides in the process and consist of cyclic reactions. Yet, due to their cyclic nature, they both need to resolve sintering-induced cyclic stability deterioration. Moreover, the structure of the metal oxides needs to be optimized to enhance the overall performance of CO₂ capture and storage. Deposition of thin film coating on the metal oxide is another way to get rid of wear and tear during the sintering process. Chemical vapor deposition or atomic layer deposition are the well-known, established methods to form thin film membranes, which will be discussed in this review. Various effective recent developments on structural modification of metal oxide and incorporation of stabilizers for cyclic stability are also discussed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.11
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• pp.4656-4663
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• 2010

In this study, the 3D computational fluid dynamics (CFD) was performed in relation to the internal fluid characteristics, flow distribution, air mean ages, and residence time for the development of the most optimal model in the complex post-disposal device. As it is expected that a channeling (drift) would be made by the semi-dry reactor due to the large difference in the flow distribution by the compartment in the bag filter, a structural improvement should be urgently made for more uniformed flow distribution in the bag filter. In addition, it showed the possibility that the velocity field and distribution characteristics of the residence time could be improved through a modification to inlet structure of the spray dryer reactor. The complex post-disposal device, modified and supplemented with this analysis, integrated the semi-dry reactor and the bag filter in a single body, so it follows that the improvement can make the device compact, the installation area, the operation fee, and management more convenient.