• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.71-71
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• 2011

Dye-sensitized solar cells (DSCs) have drawn great academic attention due to their potential as low-cost renewable energy sources. DSCs contain a nanostructured TiO2 photoanode, which is a key-component for high conversion efficiency. Particularly, one-dimensional (1-D) nanostructured photoanodes can enhance the electron transport for the efficient collection to the conducting substrate in competition with the recombination processes. This is because photoelectron colletion is determined by trapping/detrapping events along the site of the electron traps (defects, surface states, grain boundaries, and self-trapping). Therefore, 1-D nanostructured photoanodes are advantageous for the fast electron transport due to their desirable features of greatly reduced intercrystalline contacts with specified directionality. In particular, anodic TiO2 nanotube (NT) electrodes recently have been intensively explored owing to their ideal structure for application in DSCs. Besides the enhanced electron transport properties resulted from the 1-D structure, highly ordered and vertically oriented nanostructure of anodic TiO2 NT can contribute additional merits, such as enhanced electrolyte diffusion, better interfacial contact with viscous electrolytes. First, to confirm the advantages of 1-D nanostructured material for the photoelectron collection, we compared the electron transport and charge recombination characteristics between nanoparticle (NP)- and nanorod (NR)-based photoanodes in DSCs by the stepped light-induced transient measurements of photocurrent and voltage (SLIM-PCV). We confirmed that the electron lifetime of the NR-based photoanode was much longer than that of the NP-based photoanode. In addition, highly ordered and vertically oriented TiO2 NT photoanodes were prepared by electrochemical anodization method. We compared the photovoltaic properties of DSCs utilizing TiO2 NT photoanodes prepared by one-step anodization and two-step anodization. And, to reduce the charge recombination rate, energy barrier layer (ZnO, Al2O3)-coated TiO2 NTs also applied in DSC. Furthermore, we applied the TiO2 NT photoanode in DSCs using a viscous electrolyte, i.e., cobalt bipyridyl redox electrolyte, and confirmed that the pore structure of NT array can enhance the performances of this viscous electrolyte.

• Clean Technology
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• v.16 no.3
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• pp.220-228
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• 2010

Four Keggin-type heteropolyacids, $H_nXM_{12}O_{40}$(X = P and Si, M = W and Mo) that were substituted with heteroatom and polyatom were applied to the dehydration reaction of fructose to 5-hydroxymethylfurfural (HMF). The results showed that the acid became stronger when the heteroatom and polyatom were substituted with P and W than the cases of Si and Mo, respectively. However, the amount of acidic sites increased with the decrease in the acid strength, resulting in the change of the catalytic activity of heteropolyacids in the dehydration reaction. The experimental results revealed that four different heteropolyacids produced similar amounts of HMF via the dehydration reaction of fructose due to the counterbalancing effect between the amount of active sites, which is related to the catalytic activity of heteropolyacids, and the softness of polyanion. In addition, it was observed that the prepared heteropolyacids showed good structural stability after heat treatment at $200^{\circ}C$.

• The Journal of Sustainable Design and Educational Environment Research
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• v.5 no.2
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• pp.1-13
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• 2006

The purpose of this study is to clarify the actual conditions of spatial composition of educational facilities by design process model. This article discuses about the characteristics of the floor plan composition and the site plan patterns of 49 middle and high schools in gyeongnam province. The results of this study are summarized as follows; 1) Comparing to traditional middle and high school facilities, it occurs various types of plane and the area is somewhat expanded in the school with same class size, however, it needs to improve facility standards in its reality to deal with the change of future educational environment actively. 2) Spatial composition of educational facilities should functionally designed considering that the characteristics of design process model. In facilities arrangement of middle and high schools, it shows diverse forms of arrangement from existing uniform straight type, however, most of schools do not being against the simple in their external space. Therefore, it requires an expansion of space siæ and facilities for the change of school life outside class.

• Journal of Korea Society of Digital Industry and Information Management
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• v.6 no.4
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• pp.11-20
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• 2010

Ontology is important role in semantic web to construct and query semantic data. Because of dynamic characteristic of ontology, P2P environment is considered for ontology processing in web environment. For efficient processing of ontology in P2P environment, clustering of peers should be considered. When new peer is added to the network, cluster allocation problem of the new peer is important for system efficiency. For clustering of peers with similar chateristics, similarlity measure method of ontology in added peer with ontologies in other clusters is needed. In this paper, we propose similarity measure techniques of ontologies for clustering of peers. Similarity measure method in this paper considered ontology's strucural characteristics like schema, class, property. Results of experiments show that ontologies of similar topics, class, property can be allocated to the same cluster.

• Journal of Korean Society on Water Environment
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• v.27 no.5
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• pp.597-604
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• 2011

This research analyzed the runoff patterns and estimated unit loads of selected pollutatnts using monitored data conducted for three years in a bridge area. Three estimating methods; the arithmetic average method, the regression method and the rainfall class method were used to estimate the unit load. Results of three estimating methods were compared with the unit pollutant loads from landuses in Korea and the unit pollutant loads from urban watersheds in Milwaukee, USA. Unit load using the arithmetic mean method were found to be overestimated. In terms of TSS, unit loads of two estimate were half lower than that of USA. Estimated TN and TP unit loads of three estimate were lower than that of Ministry of Environment in Korea.

• Journal of Convergence for Information Technology
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• v.12 no.2
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• pp.17-22
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• 2022

Currently, the housing supply rate exceeds 100%, and the penetration rate continues to increase. This housing supply rate is changing from quantitative supply-oriented to improving the quality of the residential environment in housing service policies. Despite the increase in the housing supply rate, practical access to the vulnerable class is still difficult and there are many areas that are insufficient to use housing services when necessary. In addition, the demand for residential services is increasing due to the expansion of the scope of the vulnerable class. In order to compensate for these problems, facilities and joint occupancy that cannot guarantee independent living are mainly established, although a supply plan is established for the vulnerable by expanding policies and support projects. This paper proposes an IoT environment-based housing support system for vulnerable groups to support housing services for vulnerable groups. The proposal system improves the quality of the residential environment and provides service-oriented support services. Through the proposal system, appropriate social participation opportunities can be provided by improving the quality of life of the vulnerable and supporting a residential environment where independent living is possible.

• Journal of the Korean Society of Earth Science Education
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• v.3 no.3
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• pp.228-238
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• 2010

The purpose of this study is to examine the effects which applies teaching program that search solution to prevent global warming in middle school gifted class. This program of total 10 class was theoretical and experimental class and the students presented after collecting the synthetic data about climate-change and roleplayed what they debated to firm their country's opinion about Kyoto Protocol. Finally, students as policymaker made mock Kyoto Protocol by discussion. Impression papers and images about climate-changes was made by students in last class. In discussion of making up mock Kyoto Protocol, developed and developing nations had an argument about carbon dioxide emissions because of their economic benefits. In the course of allocating mutual $CO_2$ reduction, they needed yield and negotiation among nations. Although they mainly took passive position about $CO_2$ reduction, atmosphere that all the country make greater effort for the future global environment was formed. Like this, students had more concepts over climate change by making mock Kyoto Protocol. And they could equipped global scientific literacy and responsibility by participating in social decision making process of solving global environmental issues.

• Journal of the Korean Institute of Educational Facilities
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• v.3 no.2
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• pp.15-24
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• 1996

The purpose of this study is to establish fundamental data of architectural planning concerning location of the special class to tackle the problems of special class facilities, the contacting activities of special children with ordinary children and finally proper environment for the main-streaming education which special education persues. The contacting activities of the special class children usually take place in both their original class and special class. The less the degree of handicap is, the less contact with ordinary children happens. In the case of the serious degree of handicap, it can be said that they are often helped by ordinary children so that there are more oppotunities to make friends each other. Therefore, the disposition of special classes in a school should consider the degree of handicap. The characteristics of special class facilities and management system play significant role on contacting activities. In particular, the location of a special class in terms of grouping and floor, the character of the next space and the location of the building in the overall context should be taken into account in deciding the location of special classes in a school. In addition, the characteristics of junior and senior children should be considered.

• Human Ecology Research
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• v.58 no.4
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• pp.561-583
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• 2020

This study developed and implemented a teaching · learning process plan for Home Economics in middle school by converging Habermas's three systems of action. It also examined the effect of the class through the evaluation of students and teachers who participated in the class. This study developed 10 sessions for a teaching and learning process plan by converging three systems of action and reconstructing learning elements related to 'balanced meal plan' and 'food choice' according to the practical action teaching model. After class, we surveyed the degree of help for students, analyzed the learning activity sheets, and analyzed the reflection journals of teachers to evaluate the effects of the class. This class was found to be the most helpful in practicing the healthy dietary life of students, expanding their thoughts, understanding learning contents, and helping them change their lives. As a result of analyzing the learning activity sheet, students gained enlightenment by reflecting and evaluating their action through the class; in addition, changes in interest, awareness, and action appeared. Through the convergence of three systems of action, teachers who practiced the class criticized and realized the act that students were unconsciously accepted. In addition, it confirmed the possibility that students could change their lives, family and society by promoting optimal nutrition and health for a good life that pursues the best good.

• The Journal of the Korea institute of electronic communication sciences
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• v.17 no.6
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• pp.1213-1220
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• 2022

This study was conducted to understand how to derive educational methods to efficiently improve class satisfaction for 130 college students who experienced non-face-to-face classes during the last Covid-19. The appropriateness of class time, improvement of learning effect, continuity of non-face-to-face classes, and use of educational media were set as items corresponding to class satisfaction. Research was attempted to derive an educational method for efficient class satisfaction improvement by grasping the difference and relationship between variables.