• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.8 no.1
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• pp.19-32
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• 2010

Electrolytic reduction technology is essential for the purpose of adopting pyroprocessing into spent oxide fuel as an alternative option in a back-end fuel cycle. Spent fuel consists of various metal oxides, and each metal oxide releases an oxygen element depending on its chemical characteristic during the electrolytic reduction process. In the present work, an electrolytic reduction behavior was estimated for voloxidized spent fuel based on the assumption that each metal-oxygen system is independent and behaves as an ideal solid solution. The electrolytic reduction was considered as a combination of a Li recovery and chemical reactions between the metal oxides such as uranium oxide and the produced Li metal. The calculated result revealed that most of the metal oxides were reduced by the process. It was evaluated that a reduced fraction of lanthanide oxides increased with a decreasing $Li_2O$ concentration. However, most of the lanthanides were expected to be stable in their oxide forms. In addition, a semi-empirical model for describing $U_3O_8$ electrolytic reduction behavior was proposed by considering Li diffusion and a chemical reaction between $U_3O_8$ and Li. Experimental data was used to determine model parameters and, then, the model was applied to calculate the reduction yield with time and to estimate the required time for a 99.9% reduction.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.546-546
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• 2008

Copper (Cu) Chemical mechanical polishing (CMP) has been an essential process for Cu wifing of DRAM and NAND flash memory beyond 45nm. Copper has been employed as ideal material for interconnect and metal line due to the low resistivity and high resistant to electro-migration. Damascene process is currently used in conjunction with CMP in the fabrication of multi-level copper interconnects for advanced logic and memory devices. Cu CMP involves removal of material by the combination of chemical and mechanical action. Chemicals in slurry aid in material removal by modifying the surface film while abrasion between the particles, pad, and the modified film facilitates mechanical removal. In our research, we emphasized on the role of chemical effect of slurry on Cu CMP, especially on the effect of amine functional group on removal rate selectivity between Cu and Tantalum-nitride (TaN) film. We investigated the two different kinds of complexing agent both with amine functional group. On the one hand, Polyacrylamide as a polymer affected the stability of abrasive, viscosity of slurry and the corrosion current of copper film especially at high concentration. At higher concentration, the aggregation of abrasive particles was suppressed by the steric effect of PAM, thus showed higher fraction of small particle distribution. It also showed a fluctuation behavior of the viscosity of slurry at high shear rate due to transformation of polymer chain. Also, because of forming thick passivation layer on the surface of Cu film, the diffusion of oxidant to the Cu surface was inhibited; therefore, the corrosion current with 0.7wt% PAM was smaller than that without PAM. the polishing rate of Cu film slightly increased up to 0.3wt%, then decreased with increasing of PAM concentration. On the contrary, the polishing rate of TaN film was strongly suppressed and saturated with increasing of PAM concentration at 0.3wt%. We also studied the electrostatic interaction between abrasive particle and Cu/TaN film with different PAM concentration. On the other hand, amino-methyl-propanol (AMP) as a single molecule does not affect the stability, rheological and corrosion behavior of the slurry as the polymer PAM. The polishing behavior of TaN film and selectivity with AMP appeared the similar trend to the slurry with PAM. The polishing behavior of Cu film with AMP, however, was quite different with that of PAM. We assume this difference was originated from different compactness of surface passivation layer on the Cu film under the same concentration due to the different molecular weight of PAM and AMP.

• Journal of Service Research and Studies
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• v.9 no.3
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• pp.1-16
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• 2019

This study considers service philosophy of Western representative ideology to establish service philosophy following previous studies. The service philosophy is analyzed by referring to previous researches, and the structure and operation model of service philosophy are presented together. In the analysis of the Western representative thought by the age, the ancient Mediterranean philosophy and the Athenian philosophy were analyzed in detail from the viewpoint of the service structure, and the modern thoughts were analyzed from the perspective of the service operation model consistency. We analyze whether the intangibility and process characteristics of service are consistent with the world view of Western representative ideology and analyzed whether the essential characteristics of service, such as relationship, interactivity, horizontality, and harmony, are emphasized in Western representative ideology. Also, we examined whether the spiral development model of service matches the world development model in Western representative ideology. From the ancient thought to the modern thought, mainstream thoughts emphasize the dialectical development of the conflicts, and the Taegeuk - type basic structure of service is consistent with the world 's operating structure in Western thought. In addition, it is shown that circular reasoning and process theory are central idea from ancient times to modern thought, and process theory is consistent with service operation model which creates value. Relationality and harmoniousness are presented by the majority of Western thinkers as the fundamental operating principle of the world, and both the interactive and horizontal aspects are presented as ideal operating models of the world. It is confirmed that the service philosophy can play a central role as the ideology that leads the human society.

• Korean Journal of Environment and Ecology
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• v.25 no.4
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• pp.540-561
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• 2011

We carried out a study for ecological management and ideal vegetation structure selection on the shrine forest of 'Miwhang-sa' considering the species diversity and the vegetation structure analysis associated with global warming. We carried out the analyses of phytosociological vegetation structure, correlation between vegetation units and environmental variables, life form, species diversity, and species evenness. This study identified the vegetation units as 3 communities. The identified vegetation units are as follows: Quercus acuta community(DQ), Quercus serrata-Quercus variabilis community(QQ) and Celtis sinensis community(CS). According to the basis on the environmental variables; Ca, Mg and P, Celtis sinensis community and other communities were classified. Quecus serrata-Quercus variabilis comm. and Quercus acuta comm. were classified, according to the basis on the environmental variables; organic matter(OM), Ni and Zn. Sasa borealis as life form R1-2, dominated the herb layer and will dominate the herb and shrub layers. Species simplification is formed on herb layer and will be formed on shrub layer. The species diversity of Quercus serrata-Quercus variabilis community is higher than the one of Quercus acuta community, and the species diversity of shrine forest around Miwhang-sa was higher than the shrine forest around Nameun-sa where evergreen broad-leaved forests dominate. It is essential that the long-term vegetation management considering the vegetation units by phytosociological analysis, the species simplification problem of low layers by S. borealis and the species diversity and evenness in the shrine forest, Miwhang-sa.

• Journal of Periodontal and Implant Science
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• v.37 no.4
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• pp.733-742
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• 2007

Bone morphogenetic proteins have been shown to possess significant osteoinSductive potential, but in order to take advantage of this effect for tissue engineering, carrier systems are essential. Successful carrier systems must enable vascular and cellular invasion, allowing BMP to act as a differentiation factor. The carrier should be reproducible, non-immunogenic, moldable, and space-providing, to define the contours of the resulting bone. The purpose of this study was to review available literature, in comparing various carriers of BMP on rat calvarial defect model. The following conclusions were deduced. 1. Bone regeneration of ACS/BMP, ${\beta}-TCP/BMP$, FFSS/BMP, $FFSS/{\beta}-TCP/BMP$, MBCP/BMP group were significantly greater than the control groups. 2. Bone density in the ACS/BMP group was greater than that in ${\beta}-TCP$, FFSS, $FFSS/{\beta}-TCP$ carrier group. 3. Bone regeneration in FFSS/BMP group was less than in ACS/BMP, ${\beta}-TCP/BMP$, MBCP/BMP group. However, New bone area of $FFSS/{\beta}-TCP/BMP$ carrier group were more greater than that of FFSS/BMP group. ACS, ${\beta}-TCP$, FFSS, $FFSS/{\beta}-TCP$, MBCP were used for carrier of BMP. However, an ideal carrier which was reproducible, non-immunogenic, moldable, and space-providing did not exist. Therefore, further investigation are required in developing a new carrier system.

• Restorative Dentistry and Endodontics
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• v.20 no.2
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• pp.432-461
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• 1995

The basic principles in the design of Class II amalgam cavity preparations have been modified but not changed in essence over the last 90 years. The early essential principle was "extension for prevention". Most of the modifications have served to reduce the extent of preparation and, thus, increase the conservation of sound tooth structure. A more recent concept relating to conservative Class II cavity preparations involves elimination of occlusal preparation if no carious lesion exists in this area. To evaluate the ideal ClassII cavity preparation design, if carious lesion exists only in the interproximal area, three cavity design conditions were studied: Rodda's conventional cavity, simple proximal box cavity and proximal box cavity with retention grooves. In this study, MO amalgam cavity was prepared on maxillary first premolar. Three dimensional finite element models were made by serial photographic method. Linear, eight and six-nodal, isoparametric brick elements were used for the three dimensional finite element model. The periodontal ligament and alveolar bone surrounding the tooth were excluded in these models. Three types model(B option, Gap option and R option model) were developed. B option model was assumed perfect bonding between the restoration and cavty wall. Gap option model(Gap distance: $2{\mu}m$) was assumed the possibility of play at the interface simulated the lack of real bonding between the amalgam and cavity wall (enamel and dentin). R option model was assumed non-connection between the restoration and cavty wall. A load of 500N was applied vertically at the first node from the lingual slope of the buccal cusp tip. This study analysed the displacement, 1 and 2 direction normal stress and strain with FEM software ABAQUS Version 5.2 and hardware IRIS 4D/310 VGX Work-station. The results were as followed. 1. Rodda's cavity form model showed greater amount of displacement with other two models. 2. The stress and strain were increased on the distal marginal ridge and buccopulpal line angle in Rodda's cavity form model. 3. The stress and strain were increased on the central groove and a part of distal marginal ridge in simple proximal box model and proximal box model with retention grooves. 4. With Gap option, Rodda's cavity form model showed the greatest amount of the stress on distal marginal ridge followed by proximal box model with retention grooves and simple proximal box model in descending order. 5. With Gap option, simple proximal box model showed greater amount of stress on the central groove with proximal box model with retention grooves. 6. Retention grooves in the proximal box played the role of supporting the restorations opposing to loads.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.5
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• pp.332-338
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• 2016

This study examined the posttraumatic growth of North Korean defectors, the relation between their characteristics and posttraumatic growth and the factors influencing their posttraumatic growth, and explored methods of improving their mental health status. 145 North Korean defectors, who were trained in B city and G city, participated in the survey from February 1 to March 10, 2016. The posttraumatic growth, resilience, self-esteem, deliberate rumination, and impact of the (traumatic) event were measured using the PTGI (Posttraumatic Growth Inventory), RS (Rumination Scale, Resilience Scale), SES (Self-esteem Scale) and ISR (Impact of Event). The data were analyzed using the t-test, ANOVA, Pearson correlation coefficient and stepwise multiple regression. The mean scores were 29.64 for posttraumatic growth. There were significant positive correlations between posttraumatic growth and resilience and between posttraumatic growth and rumination. The influence of the independent variables on the total posttraumatic growth was examined using regression analysis. Models including the variables (resilience, positive self-esteem, and rumination) explained 54.2% of the variance for the posttraumatic growth. These findings demonstrate that it is essential for nurses to continuously intervene and help North Korean defectors so as to promote their posttraumatic growth and resilience. Furthermore, it is also necessary for nurses to find ways to develop ideal interventions in order to activate deliberate rumination.

• Molecules and Cells
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• v.41 no.12
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• pp.1016-1023
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• 2018

Regenerative orthopedics needs significant devices to transplant human stem cells into damaged tissue and encourage automatic growth into replacements suitable for the human skeleton. Soft biomaterials have similarities in mechanical, structural and architectural properties to natural extracellular matrix (ECM), but often lack essential ECM molecules and signals. Here we engineer mineralized polysaccharide beads to transform MSCs into osteogenic cells and osteoid tissue for transplantation. Bone morphogenic proteins (BMP-2) and indispensable ECM proteins both directed differentiation inside alginate beads. Laminin and collagen IV basement membrane matrix proteins fixed and organized MSCs onto the alginate matrix, and BMP-2 drove differentiation, osteoid tissue self-assembly, and small-scale mineralization. Augmentation of alginate is necessary, and we showed that a few rationally selected small proteins from the basement membrane (BM) compartment of the ECM were sufficient to up-regulate cell expression of Runx-2 and osteocalcin for osteoid formation, resulting in Alizarin red-positive mineral nodules. More significantly, nested BMP-2 and BM beads added to a non-union skull defect, self-generated osteoid expressing osteopontin (OPN) and osteocalcin (OCN) in a chain along the defect, at only four weeks, establishing a framework for complete regeneration expected in 6 and 12 weeks. Alginate beads are beneficial surgical devices for transplanting therapeutic cells in programmed (by the ECM components and alginate-chitosan properties) reaction environments ideal for promoting bone tissue.

• Art History and Visual Culture
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• no.22
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• pp.254-279
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• 2018

This essay traces the origin and the social function of medieval knights in Edwin Austin Abbey's murals ${\ll}$The Quest of the Holy Grail${\gg}$ in the Boston Public Library. Medieval knights in the Arthurian legend appeared in American novels at the end of 1850s and in political cartoons in the 1870s. They are featured in American Renaissance murals as well. ${\ll}$The Quest of the Holy Grail${\gg}$ painted in 1895 was the first of its kind. In Britain, the Pre-Raphaelites frequently painted medieval knights. Abbey fused the visual idiom of the Pre-Raphaelites and that of the Royal Academy of Arts in his depiction of knights. Unlike the Pre-Raphaelites, who usually focused on knights' activities, he emphasized their virtue. His representation of knights reflect the social and economic crises in America in the 1890s. After the Civil War, American society enjoyed economic prosperity but suffered from government corruption, economic inequality, and class conflict. Serious social problems such as poverty and inequality decayed American society. Writers and artists brought attention to these issues. This essay argues that Abbey criticized capitalists and expressed his hope for progress through the figure of Galahad as the iconic representation of civic virtue in ${\ll}$The Quest of the Holy Grail${\gg}$. Installed in the Boston Public Library, Abbey's murals performed a public function to warn the viewers of economic and social chaos resulting from government corruption. Abbey's American knights not only emphasized moral responsibility but also promoted patriotism. The artist refashioned medieval knights into American citizens, whose civic virtue became essential to an ideal leader in American society.

• The Journal of Korean Philosophical History
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• no.42
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• pp.105-131
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• 2014

The moral categories in the Mengzi have a close affinity with those of Kongzi. Mengzi fostered the Kongzi's teaching on virtuous rule and moral government, and taught benevolent government based on the virtue of benevolence. Mengzi set up a basis for Confucian teaching on human nature, and his teaching of the essential goodness of human nature has been accepted by most Confucian intellectuals. This study explores the Mengzi's teaching of moral education focussing on his instructional method to expand the goodness of human nature. Instructional method refers to educator-centered transmission of values, and it concerns mainly on how to deliver the educational goal and content meaningfully to the educatee. The main concerns of Mengzi's instructional method are teaching-standard setup, delivery of lecture key points, understanding of students' talent and situation, and encouragement of students' initiative. These points are all based on Mengzi's assertion of good human nature, and aim at forming a ideal personality. Confucian ideas of education lie in raising the well-rounded person through moral education. The well-rounded person can be characterized by noble men and sages with benevolence and righteousness. This means that the ultimate goal of well-rounded education is to lead people to attain the sublime moral stage through education.